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Presentation on theme: "PRODUCT TESTING."— Presentation transcript:


2 Corporate Training & Planning
CONTENTS Introduction Pipes & Fittings Plastic Films & Laminates. Containers Woven Sacks Plastic Flooring Cellular Plastics Testing of FRP References Corporate Training & Planning

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INTRODUCTION Importance of product testing: To evaluate the performance of product. To identify criticality of component performance in assembled condition. To identify necessary changes in process parameters. Modification of product or mould design. To prepare instructions to avoid end user’s abuse. To establish the reputation of the product. Conformity of product to particular specifications. Corporate Training & Planning

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INTRODUCTION Factors Responsible for Performance Products Materials and its grade Additives,modifiers and processing aids. Plastic Processing Techniques e.g.Injection olding, Extrusion, Compression molding etc. Processing Parameters (e.g. Pressure,Temperature & Time etc.) Pre Molding Operations e.g.Pre-heating,Pre-forming, compounding, Blending etc. Post Molding operations such as Printing, decoration, drilling, trimming, electroplating, welding etc. Mould & Product Design End use conditions(e.g.Environmental condition,final assembly etc.) Corporate Training & Planning

Pipes and Fittings Plastic Films and Laminates. Plastic Containers Woven Sacks Plastic Flooring Cellular Plastics Testing of FRP Corporate Training & Planning

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TESTING OF PIPES & FITTINGS Corporate Training & Planning

Introduction Definition : Pipe is any round self – supporting continuous hollow cylinder with a minimum inside diameter of 12mm. Fittings Corporate Training & Planning

Advantages of Plastic Following are the advantages of plastic pipes Low manufacturing cost. Lighter in weight and easy to handle. Flexibility in design features. Easy assembling & installation High resistance to corrosion , water & Chemicals Good weathering properties. Low maintenance cost Less chance to microbial growth inside pipe. Low friction loss in transportation of water More durability ( Life of UPVC pipe is estimated approx 100 years) Corporate Training & Planning

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APPLICATIONS OF PIPES Potable water supply Tube-well construction Domestic/Industrial Plumbing Cable Duct Pipes Soil, Waste & Rain water systems Underground drainage and sewerage systems Lift Irrigation system Agriculture irrigation distribution systems Subsoil drainage systems Piping system for both fresh and salt waters Effluent Treatment conveyance pipeline systems Chemical conveying pipeline systems in industry Centrifugal pump suction and delivery pipes Corporate Training & Planning

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MATERIALS FOR PIPES Commonly used plastic materials for pipes are Polyvinyl Chloride (PVC) Chlorinated Polyvinyl chloride(CPVC) Acrylonitrile Butadiene Styrene(ABS) Polypropylene(PP) Polyethylene(HDPE, LDPE etc) Fiberglass Reinforced Plastic Epoxy(FRPE) Fiberglass Reinforced Plastic Polyester (FRPP) Material selection Selection of correct piping material depends on application and environment. Ex : PP is preferred for chemical resistant & high temperature applications. ABS is preferred for high impact and crush resistant applications. Corporate Training & Planning

Materials Properties Application PVC Excellent weather resistance Refrigeration, Sewage & water treatment, Chemical & food processing industries, Irrigation and water distribution line, swimming, drain, waste and vent, conduct for wiring and vacuum lines CPVC Stand higher temperature Hot fluid application and water treatment systems ABS Good chemical resistance weather resistance. Does not crack on impact Weather and gas marked, food process plant, chemical, drainage, sewage treatment, sludge discharge system, electrical conducts irrigation lines (UHMW-PE) PP Light weight and good high temperature and chemical resistance Low pressure line and Acid waste drainage system one and water system

Materials Properties Application Polyvinylidene Chloride -- Lining material in steel pipes and fittings FRP (Epoxy) Resistance to dilute acid, solvents, caustics Chilled and hot water line, Air-conditioned and refrigerator FRP (Polyester) Good corresion resistance, good weather resistance Water line for power plant discharge line, Water faintain service lines Petroleum, refining installations

13 COMMONLY MANUFACTURED PIPES Specified Tests on pipe as per standard
& RECOMMENDED TESTS Description IS/ASTM No. Specified Tests on pipe as per standard Unclassified PVC pipe for potable water supply IS:4985 : 2000  Dimensions( Diameter, Wall thickness, Socket ID, Length, Socket dimension)  Opacity,  Sulphated Ash content  Reversion  Visual appearance  Density  Resistance to external blow at 00 C  Hydraulic test  Effect on water test  Long term (Analysis of Pb, Sn, Cd & Hg in  Short term water extracted from pipe) UPVC Screen and casing pipe for bore well/ Tube well IS:12818: 1992  Dimensions ( Diameters, Wall thickness, Length)  Visual appearance  Specific Gravity  Shore A hardness of Rubber gaskets  Mandrel test  Impact resistance  Tensile strength  Vicat Softing Temp.  Effect on water test (Analysis of Pb, Sn, Cd & Hg in water extracted from pipe)

& RECOMMENDED TESTS PVC pipe Plastic pipes, Schedule 40, 80 and 120 ASTMD : 1785:04a  Dimension,  Visual appearance, Flattening test  Burst pressure, Sustained press.  Crush resistance,  Acetone immersion test UPVC pipe for soil & waste discharge system IS:13592:1992  Dimensions(Diameter, wall thickness, Length,Socket dimensions)  Visual appearance  Reversion  Stress relief test  Resistance to H2So4  Impact resistance at 00 C  Tensile strength,  Vicat Softing Temp.  Water tightness of joints HDPE Pipes for potable water supply IS: 4984: 1995 Grade PE 63 PE 80 PE 100  Dimensions(Diameter, wall thickness)  Reversion  Migration,  Density  Melt Flow Index(1900C/5kg.)  Carbon black content  Carbon black dispersion  Hydraulic characteristics Long term (165 hrs.) Short term (48 hrs)

& RECOMMENDED TESTS PE Pipes for irrigation laterals IS: : 1989  Dimensions(Diameter, wall thickness)  Hydraulic characteristics  Reversion  Tensile strength  Environmental stress crack resistance PE pipes for sprinkler irrigation system IS: 14151: (Pt-I)1999  Dimensions(Diameter, wall thickness, Ovality)  Visual Appearance  Tensile strength and elongation  Fusion compatibility,  Hydraulic characteristic  Density  Melt Flow Index  Carbon black content  Carbon black dispersion IS: 14151: (Pt-II)1999  Visual Appearance  Leakage test  Hydraulic proof test  Density  Melt Flow Index,  Carbon black dispersion,  Shore hardness Corporate Training & Planning

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PRODUCT SELECTION The Selection of correct piping material for specific application depend upon many factors . These are : The selection of correct piping depends as the application and environment. Example For chemical resistant & high temperature applications, Polypropylene pipes are preferred. For high impact and crush resistant applications pipes of ABS material are suitable. Corporate Training & Planning

Almost all the pipes are classified by pressure rating at a given temperature As per IS : 4984 : 1995 at 300C and IS : 4985: 2000 at 27oC pressure ratings of pipes are according to their nominal pressure (PN) as below. Other pipes & fittings manufactured according to IS standards are classified on similar pressure rating. Generally swegger and drainage pipe are not rated based on the pressure S.No. Nominal Pressure Class 1. 0.25 MPa Class 1 2. 0.4 MPa Class 2, 3. 0.6 MPa Class 3, 4. 0.8 MPa Class 4 5. 1.0 MPa Class 5 6. 1.25 MPa Class 6 Corporate Training & Planning

In USA standard dimension ratio ( SDR) is used to classify the pressure rating of thermoplastic pipe. Standard dimension ratio ( SDR ) = Outside diameter of pipe Wall thickness of pipe Thermo sets pipes are normally rating at maximum temperature where as thermoplastic at ambient temperature ( 740F – 750F ) The most popular ratings are as below. Thermo plastic pipes are designated with four digits and product alphabet prefix 1st digit = Type of resin 2nd digit = Grade of resin according to ASTM 3rd & 4th digit = Hydrostatic design stress divided by 100 Example : CPVC 4120 means the resin is CPVC type 4, Grade 1, with a 2000 psi hydrostatic design stress S.No. SDR of pipes Nominal Pressure 1. 13.5 315psi 32.5 125psi 2. 17 250psi 41 100psi 3. 21 200psi 64 50psi 4. 26 160psi - Corporate Training & Planning

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TEST PROCEDURES Opacity Test : (IS: 4985:2000, (Part-3 ) This test determines the percentage of visible light transmission through the wall of PVC pipe. The transmission of the light through the wall of pipe & fitting should not be more than < 0.2% Significance : To check the conformity to the pipe & fittings to opacity test as per IS: 4985:2000 of relevant standard. The transmission of the light through the wall of the pipe will caused photochemical reaction inside the pipe in the presence of heat and water Such photochemical leads to scaling, algae formation and contaminate the potable water transported though the pipe and make unsuitable for drinking Light transmission is generally high in thin wall pipe & less in thick wall pipes When the light transmission is less than 0.2% the effect of Photochemical reaction and it’s effect will be insignificant The additional of small amount of carbon black in PVC compound improves opacity ( reduces light transmission ) Apparatus : Electronic opacity tester is used which consists of light source, photo electric cell, digital current meter Corporate Training & Planning

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TEST PROCEDURES PROCEDURE: Cut 2 nos of 50mm x 50mm test pieces from the original thickness of the pipe & fitting. Calibrate the equipment by adjusting the reading to zero by blocking the light from the light source fully and 100% when the light is switched in absence of test piece. Check the precision of reading using standard lens to give absorption of 0.2% Place the specimen on the support between the light source and photo detector cell The percentage light transmitted is directly read from the opacity indicator The percentage of light transmission should not exceed 0.2% Result : The percentage of light transmission through the wall of the pipes is recorded as its result Factors affecting opacity Amount of the carbon black, and other compound in the pipe material Wall thickness of the pipe( higher the wall thickness less is the opacity) Corporate Training & Planning

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REVERSION TEST Definition : Change in length along the surface of the pipe due to heat and subsequent cooling is called reversion. This test is recommended for UPVC and PE pipes. The test is carried out by emerging a portion of pipe of a given length in the liquid or air medium for a specified period of time in relation to wall thickness and dia of the pipe Significance : To check the conformity to the pipe to reversion test as per relevant standard. During manufacturing of pipe certain degree of moulded in stresses ( residual stresses) and high degree of molecular orientation are introduced. These molecular orientation and stresses get relived by reversing on reheating. Due to high day & night temperature variation in different environmental conditions the pipe undergoes expansion, contraction & stress relaxation process which leads to the change in dimension. The pipe expands and contracts with the rise and fall of the temperature which leads to the failure of assembly particularly joints and water leakage may occur The dimensional change in the longitudinal direction is measure on cooling to room temperature. The acceptable limit of dimensional change is specified as per pipe material. Corporate Training & Planning

S.No IS No. Pipe Sample Details Sample Size Test Temp. Test Duration Medium of heating A For HDPE pipes 1. IS 4984:1995 HDPE Pipes for Water Supply 200±20mm 110+2 60 /120/240 minutes ( for 8mm/8 to 16mm/16mm and above thick pipe) Air 2. IS : (part-I) 1999 HDPE pipe for Sprinkler irrigation 60 min 3. IS : 1996 HDPE pipe for sewerage 4. IS 12786:1989 Irrigation Equipment-PE Pipes for Irrigation Laterals 100+2

S.No IS No. Pipe Sample Details Sample Size Test Temp. Test Duration Medium of heating 5. IS 4985:2000 UPVC Pipes for Potable water Supply 200±20mm 150+2 15min / 30 / 60 minutes (8.6 mm / 8.6 to 14mm/>14mm & above respectively. Liquid 6. IS 13592:1992 UPVC Pipes for soil & waste discharge systems inside buildings including ventilation & rain water system 60min / 120 / 240 minutes Air 15min/30min/60min (8.6 mm / 8.6 to 14mm/>14mm & above respectively)

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REVERSION TEST EQUIPMENTS :  Electrical heated hot air oven (for HDPE pipes) Vernier caliper  Oil immersion bath ( for UPVC pipes)  Scriber PROCEDURE : Cut the 3 pieces of 200 ± 20mm long piece of pipe in the axial length and scribe two lines at outside of surface of specimen 100mm apart For HDPE pipe >200mm dia test piece from the circumferential arc of length of 200mm is cut from the pipe and scribe two line 100mm apart Select the specified test conditions for various types of the pipe as given below in the table and set the required temperature in the air oven/oil bath as may be applicable for particular type of pipe REVERSION TEST FOR HDPE PIPE Place the duly marked test sample into the oven for the specified period of time in the air oven at at the temperature indicated in the table Remove the specimen from the oven after specified period and cool in air to ambient temperature The distance between two marked along the surface of the specimen is measured. Corporate Training & Planning

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REVERSION TEST The percentage of Reversion is calculated using the following formula R ( % ) = lo – li x lo where R is the reversion, lo and li are the lengths before and after test. Oil Immersion method : ( For UPVC pipes ) Marked UPVC pipe specimens are immersed in an oil bath at oC for a specified duration as given in the table according to the wall thickness of the pipe. After expiry of the test duration specimens is removed from oil bath and cooled in air to ambient temperature. The percentage reversion is calculated using the above formula. The maximum reversion percentage limits for HDPE pipes is + 3 % while that for UPVC pipes is + 5 %. Corporate Training & Planning

The most important and commonly used pressure tests are (i) Acceptance or test Short term test (ii ) Type test or Quality also known as test Long term test (iii) Brust pressure (i) Acceptance (Short term test) :- Short term testing is called instantaneous pressure test. This test is generally used for quality control test and to check batch to batch uniformity for acceptance of materials. Under this test pipes are brought to specified temp and pressure and then instantaneously pressure is increased to burst or maintained for specified test time. Corporate Training & Planning

(ii) Type test (Long term test) : - In this test pipes are held at standard condition of sure and time (between 100 to 1000 hours). The constant temp and pressure is maintained for the specified period. The failure or bursting of the pipes are observed. The long term or Quality test is generally carried out to characterize material and prove the suitability and performance ( creep resistance ) of new composition or new size of pipe. The test conditions for various pipes is given in table 1 Brust Pressure : Under this test pipe is subjected to Hydrostatic pressure and increased to it’s maximum brust pressure. Corporate Training & Planning

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MECHANISM OF FAILURE Pipe failed by two mechanism I.e Creep & Creep propagation CREEP : Creep cause a gradual increase internal volume, thinning of the wall and increased in pipe diameter and length The variation in the dimension or in material causes differential creep with HDPE pipes Localized yielding and ruptured leads to the ductile failure When the pipes are subjected to internal hydrostatic pressure test, generally two types of stress component are developed inside the pipe i.e ( shown in figure ) ( i) Longitudinal stress (ii) circumferential stress or hoop stress. The amount of hoop stress is generally two times higher than longitudinal stress. Thus it is the single largest stress present in pipe system under pressure responsible for failure of pipe. Corporate Training & Planning

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MECHANISM OF FAILURE The hoop stress is expressed by following formula. S = P ( D – t ) / 2t Where, S = Hoop stress ; P = Internal pressure ; D = Outside diameter of pipe t = Minimum wall thickness of pipes TYPES OF FAILURE Failure in the pipe may be either brittle or ductile. Brittle failure is common in rigid pipe such as PVC where as ductile failure in tough and elongation material such as P.E Corporate Training & Planning

The standard conditions for hydrostatstic pressure test for various types of pipes according to IS speciation is as below. Sl. No. IS No. Tests Length of test sample Test temp. (0C) Test Duration (Minimum holding time in hr) Induced stress (MPa) 1. IS 4984:1995 Acceptance test X10 of OD of pipe but less than 250mm & more than 750mm 80 48 3.8 (for PE 63) 4.9 (for PE 80) 5.5 (for PE 100) Type test -do- 165 4.6 (for PE 80) 2. IS 4985:2000 27 1 4.19XPN 60 1000 1.16XPN 3. IS 4.1 3.5 4. IS 12786:1989 20 6.9 Quality test 70 100 2.5 5. IS 14151 (Pt-I):1999 5.4 5.0 Corporate Training & Planning

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INTERNAL HYDROSTATIC PRESSURE (Acceptance Test for UPVC pipe as IS : 4985:2000) Definition : It may be defined as ability of the pipe to withstand a specified constant hydrostatic pressure for specified period of time at specified temperature without showing any failure It consists of subjecting the specified length of pipe to a constant internal pressure at constant temperature for a specified period of time Significance : To check the conformity of the pipe to hydrostatic pressure test (Acceptance test) for one hour to IS : 4985 : 2000 Apparatus : Hydrostatic pressure machine capable to maintain required test pressure automatically Standard end fittings and other accessories Thermostatically controlled water bath Specimens : The pipe samples shall be cut in the length of equal to 10 times of Outside Diameter of the pipe but it shall not less than 250mm or greater than 750 mm as free length Corporate Training & Planning

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INTERNAL HYDROSTATIC PRESSURE (Acceptance Test for UPVC pipe as IS : 4985:2000) PROCEDURE : Attach end plugs at both end of the pipes such that internal pressure is exerted and transmitted to the pipe. Fill the pipe with water at ambient temperature through a closable opening in end of the pipe Immerse the pipe in a water bath maintained at 270C Calculate the test pressure by multiplying 4.19 times of working pressure of the pipe Increase the pressure gradually in the test assembly to a test pressure without sock preferably within 10 to 30 seconds. Maintained the test pressure in the pipe for one hour At the end of one hour observed the pipe for the any kind of failure Record the observation of the test and it’s result Result : The pipe should not burst or ruptured or failure with in one hour of the test Corporate Training & Planning

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INTERNAL HYDROSTATIC PRESSURE (Type Test for UPVC pipe as IS : 4985:2000) Definition : It may be defined as ability of the pipe to withstand a specified constant hydrostatic pressure for specified period of time at specified temperature without showing any failure It consists of subjecting the specified length of pipe to a constant internal pressure at constant temperature for a specified period of time Significance : To check the conformity of the pipe to hydrostatic pressure test (Type test) for one hour to IS : 4985 : 2000 Apparatus : Hydrostatic pressure machine capable to maintain required test pressure automatically Standard end fittings and other accessories Thermostatically controlled water bath Specimens : The pipe samples shall be cut in the length of equal to 10 times of Outside Diameter of the pipe but it shall not less than 250mm or greater than 750 mm as free length Corporate Training & Planning

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INTERNAL HYDROSTATIC PRESSURE (Type Test for UPVC pipe as IS : 4985:2000) PROCEDURE Attach end plugs at both end of the pipes such that internal pressure is exerted and transmitted to the pipe. Fill the pipe with water at ambient temperature through a closable opening in end of the pipe. Immerse the pipe in a water bath maintained at 600C . Calculate the test pressure by multiplying 4.16 times of working pressure of the pipe. Increase the pressure gradually in the test assembly to a test pressure without sock preferably within 10 to 30 seconds. Maintained the test pressure at constant temperature of 600C in the pipe for 1000 hours. At the end of 1000 hours observed the pipe for the any kind of failure . Record the observation of the test and it’s result . Result : The pipe should not burst or ruptured or failure with in one hour of the test. The hydrostatic pressure test for remaining other pipes shall be conducted following the above procedure at the pressure, temperature and duration. Corporate Training & Planning

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BURST STRENGTH TEST Introduction: Burst strength test determine the ability of a plastic pressure vessel to resist rupture when it is pressurized for a short period of time In this test the plastics pipes are subjected to a very high internal pressure for short period of time. Time and rupture strength is determined by continuously increasing internal hydraulic pressure at controlled temperature and environmental conditional. Procedure: Specimens of 150 mm length are cut from the pipe. Specimens are attached with end fittings at both the ends and filled with water. Pipes are connected to hydrostatic pressure testing machine and the pressure is increased uniformly and continuously until the sample. The pressure at which pipe bursts and time to failure are recorded. Corporate Training & Planning

Introduction: The physical properties , dimensions ,finish and performance of pipes is influenced by the fillers compound. This also influences the specific gravity of the pipe specific gravity of the pipe. It provides advantageous effects up to certain limit. But beyond the recommended limit the quality and performance of the pipe is affected. The test is carried out by calcinations with sulphuric acid and treatment after combustion by burning the substance and transforming the residue into the sulphates using concern H2So4 and finally heating the residue at 8500C until constant mass is reached. The detailed procedure is given below. Definition: It may defend as the percentage of the ash quantitatively present in the pipe after heating, paralysis and calcinations with sulphuric acid after combustion. Significance :  For the quality control of the pipe To check the conformity of the pipe to sulphated ash content as per IS:485:2000 Corporate Training & Planning

REAGENT : Concentrated Sulphuric Acid (Density 1840 kg/cm2 ) EQUIPMENTS Crucible : Silica or Platinum crucible having upper diameter between 45 – 75mm and height equal to diameter of crucible Analytical : Analytical weighting balance capable of weighing sample and crucible to the accuracy of 01 mg. Bunsen Burner: Bunsen Burner and tripod stand or other suitable heating device. Muffle Furnace : Muffle furnace capable of maintaining temp of 850 ± 100 C Pipette : Glass Pipette of appropriate capacity. Dessicator : Dessicator with Cacl2 as drying agent for cooling the crucible. Tongue : The tongue of sufficient length for handling crucible in hot condition. Sample : Small cut pieces of the pipe approximately 10 to 15gm Conditioning : Wash and clean the crucible and heat in the muffle furnace at 8500C until the constant mass is achieved. Corporate Training & Planning

PROCEDURE : Take the mass of crucible and put about 2- 5gms samples cut from pipe. The weight of the sample along with the crucible is taken Sample is heated on bunsen burner until evolving of smoke from sample is ceased. Then it is allowed to cool. After cooling Sulphuric Acid is added to the residue drop wise by means of pipette until residue is soaked completely. Subsequently It is again heated on the burner until evolution of smoke ceases. The crucible is placed in a muffle furnace maintained at oC and heated until the constant mass is reached. The crucible is allowed to cool in a desiccator to room temp and the mass is taken The mass of the residue is recorded of as sulphated ash content CALCULATION & RESULT The sulphated ash content is calculated as follows: % Sulphated Ash Content (By mass) = Mass of residue x Mass of sample The sulphated ash content should be within the specified limit. Corporate Training & Planning

 INTRODUCTION : Impact resistance property of pipe has considerable importance. The ability of pipe to withstand socking load is a decisive factor. Therefore in order to ensure satisfactory field performance of unplasticized PVC pipe, the measurement of impact resistance at low temperature is important. SCOPE : This test method covers to the determination of resistance of external blow at 00 C for UPVC pipe as IS:4985: 2000 DEFINITION : TRUE IMPACT RATE : The total number of failure divided by total number of blows as a percentage as if whole both had been testes Failure : Shattering or any crack or spilt on inside of the pipe that was caused by the impact and that can be seen by naked eye (lightning devices may be used to assist is examining the specimen Corporate Training & Planning

SIGNIFICANCE : Impact strength signifies the toughness of the pipe and hence that the ability withstand socking load The test is used for quality control of the pipe To check the conformity of the pipe to resistance to the external blow at 00 C as per IS:4985:2000 FACTORS AFFECTING: The impact resistance of plastic not only depends basis properties of materials, but also on many factors such as environmental condition, nature of blow frequency of sock etc. EQUIPMENTS Free falling the impact tester which mainly consists of a rigidly fixed main frame A striker of standard mass with free movement on a guide A specimen support comprising of 120o steel V block at least 250 mm long A release mechanism for the striker Suitable deep freezer/ liquid bath capable of maintaining temperature 0 ± 10 C Corporate Training & Planning

SPECIMEN : Sufficient no. of cut pieces of pipe of 200± 10mm long to achieve minimum 40 strike The no. of test pieces may be more in case of failure. marked on circumference at equidistance of 50mm to take one strike. The pipes Pipes below 40mm size are tested for only one strike CONDITIONING : Pipe samples are conditioning in deep freezer/ liquid bath according to their wall thickness as given below Wall thickness Conditioning period minutes (mm) Liquid bath Air Up to 8.6 15 60 8.6 to 14.1 30 120 Above 14.1 240 Corporate Training & Planning

PROCEDURE The type and mass of the striker and height of free fall from is selected according to the nominal diameter of the pipe from Table – 9 of IS:4985:2000 The test height is measured in the equipment and marked for test Condition the specimen at 00C ± 1 for the specified period is taken out from the liquid bath/ deep freezer and is placed on “V-Block” The specified mass of the striker is allowed fall freely on the test specimen at different marked points on its outer surface by rotating the specimen about it’s axis PROCEDURE The process is continued until all marked lines have been tested or until a failure as a result of cracking of splitting is recorded Pipes their shall be no failure at the pipe upto 39 strikes. However, test and it’s conformity can be made according table-11 of IS:4985:2000 FACTORS AFFECTING : The composition of the material and filler content in the compound Fusion& Homogeneity of the compound Processing conditions and parameters Amount of impact modifier in the compound Corporate Training & Planning

INTRODUCTION: In the process of the UPVC pipe some additives, such as organo –metallic salts are used as stabilizers. These stabilizers are based on heavy metal compounds of Pb, Sn, Cd & Hg. etc At a time one are more than one of these stabilizers in the compound may be used. As such a portion of these compounds gets consumed during the processing of pipe but remaining portion present in pipe may leach in when coming in contact of water and produced a toxic effect to potable water. This affects the quality of water as well as causes health hazard. SIGNIFICANCE : This test is carried out to check that UPVC pipes manufactured pipe are safe for transportation of drinking water or not To develop PVC compound and verify manufacturing process Corporate Training & Planning

EQUIPMENT : Pre-washing arrangement of pipes before test, locking with arrangements PE stopper, Arrangement for Extraction and collection of water sample UV visible spectrophotometer/ atomic absorption spectrophotometer with graphite furnace and hydradide generator and lamp for detection of Pb, Sn, Cd & Hg. SPECIMEN : A cut pieces of the pipe of one meter length Extraction of water sample : Test sample for this test is obtained by flowing water continuously through the pipe for six hours. Subsequently pipes are filled with carbonized water by closing it’s one end. The extracts of water are collected at specified time interval. Corporate Training & Planning

PROCEDURE : The quantitative analysis of substances present in the extracted water sample like Lead, Tin, Cadmium, Mercury etc is carried out by analytical or instrumental method, using UV visible spectrophotometer or atomic absorption spectrophotometer. The quantitative analysis of these toxic substances in water sample by atomic absorption spectrophotometer is very fast and accurate. RESULT The toxic substance shall not exceed the following concentration Lead (I ext) mg/I (1.0 ppm) Lead (III ext) mg/I (1.3 ppm) Sn (III ext) mg/I (0.02 ppm) Cd (All III ext) mg/I (0.01 ppm) Hg ( All IIII ext) mg/I (0.01 ppm) Corporate Training & Planning

INTRODUCTION : During manufacturing or fabrication of sockets some degree of moulded in stress are introduced in the socket particularly in the expanded portion. These moulded in stress weaken the pipes and fittings this leads to localized failure. Test is conducted by subjecting bell ended/ socketed portion of UPVC pipes and fittings in hot air oven at 150 ± 20C temperature for one hour then cooled slowly to the room temperature and visually examined for a verity of attributes DEFINITION : It may defined as the process of heating the test portion and subsequently cooling and examining for the any warpage, blistering, wall separation, fish scaling and distortion in the component Corporate Training & Planning

SIGNIFICANCE : This test indicates the label of moulded in stress at expanded portion of the socket/ Bell end portion by observing/ checking of the severity of the war page , blistering, wall separation & distortion etc. The stress indicates level of weaken of the product Test is used for quality control and R&D purpose The test is carried out to very the conformity of UPVC pipes and fittings to relevant IS specification. EQUIPMENT : Hot air oven capable of maintaining 150 ± 20C temperature Profile projector, Micrometer etc. TEST SAMPLE : Bell ended/ expanded portion of UPVC pipe & fittings Corporate Training & Planning

PROCEDURE : Socket end of pipes & fittings is taken marked two parallel lines both side is taken about 25mm apart from the stress prone area. Test temperature of 150 ± 20C is maintained in air oven and marked pipes/ fittings are placed in the oven for one hour. After one hour the samples are removed from oven and cooled room temperature Socketed portion is visually examined for any blister, excessive delaminating or cracking sign of weld line splitting by sectioning the marked line. RESULT: Observation of visual examination is recorded FACTORS EFFECTING : Design and wall thickness of the pipes and fittings. Process temperature and rate of cooling during moulding in fabrication Material and it’s composition Corporate Training & Planning

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DENSITY FOR HDPE PIPES SIGNIFICANCE: Density of the polyethylene material is important because properties of pipe such as rigidity, it’s hydraulic characteristics, creep and other performance of pipe depends upon the density of base polymer & compounds. Butyl acetate is for determination of density by displacement method. PROCEDURE: Butyl acetate is taken in suitable container and its density is measured by hydrometer. Test piece of suitable size is cut from the pipe and is attached with fine Nylon wire for hanging in weighing balance. Mass of specimen in air is taken accurately to 0.1 mg. Beaker filled with butyl acetate is placed under the sample hanging with wire and mass of sample is taken in butyl acetate. Corporate Training & Planning

51 DENSITY The Density is calculated as below:
Density of Polyethylene Kg/m3 = a x ρBAC x a1 - a2 Where, a1 = mass in g of specimen in air a2 = mass in g of specimen in butyl acetate ρBAC = Density of butyl acetate. FOR UPVC PIPES : SIGNIFICANCE : Similarly density of RPVC pipe is used for quality control test. This test may be the indicator of compound and batch uniformity and hence quality consistency of the pipe. Corporate Training & Planning

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DENSITY PROCEDURE: Test is carried out by cutting test piece of suitable size having mass in the range of 2-5 gms Edges of specimens are cleaned so that there are no fibers. Tie specimen is with wire/Nylon fiber. and mass of specimen is taken in air and recorded as ‘a’. Specimen is immersed in distilled water and the mass of specimen is taken in immersion liquid as ‘b’. CALCULATION : The density is calculated as: Density = a x d a – b Where, d = Density of medium a = mass in grams of specimen in air and b = mass in grams of specimen in water. Corporate Training & Planning

INTRODUCTION: This test is used for evaluation of quality of extrusion of UPVC pipes. Due to some improper fusion and processing defects pipe may exhibit some residual stress which may cause product failure. PROCEDURE: A specimen is cut from complete circumferential section of the pipe. The acetone is dried by anhydrous calcium sulphate, which is removed from acetone by filtering. The specimen is immersed into reagent grade acetone for 20 minutes at oC. After the immersion, the specimen is removed and examined for any failure. Corporate Training & Planning

PROCEDURE: A piece of plane ended pipe and a piece of socket end pipe & sealing device are taken and assembled properly. End plug is attached at both free ends of specimen and is filled with water at ambient temperature through a closable opening at one end. Pressure is increased gradually to 0.5 MPa without sock. The leakage of water is observed at the joint of fitting & sealing device under pressure. Joints of pipe shall not show any leakage at the socket end Corporate Training & Planning

DEFINITION : It is defined s the ability of pipe and moulded product to resist compressive load. SIGNIFICANCE : To characterized the load defection characteristics of the moulded and extruded products under parallel plate loading For quality control and development of product & material To verify conformity of the product to relevant standard and specifications EQUIPMENT : Crush resistance tester fitted with rigid parallel plate and capable of apply compressive load and measure the compressive load and resulting deflection Vernier caliper & measuring scale for measurement of diameter before or after test Specimen : Three cut pieces of pipe each of 50mm long Corporate Training & Planning

PROCEDURE Internal/ external diameter and wall thickness of cut pipe piece of measure and place between two parallel plates of cross tester Machine is brought just in contact of test sample and compressive load is applied at uniform rate on the sample until the distance between the to plate is reduced to 50 % of the diameter Compression process should be completed preferably within 2 to 5 minutes Test sample is relived from compressive load and observed for any splitting, cracking, fracture or breaking RESULT : Any splitting, cracking or braking is noted as a failure Factors affecting Material and it’s composition affect the result Design of moulded and fabricated product Residual Stress/ moulded in stress in the product Corporate Training & Planning

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CARBON BLACK CONTENT INTRODUCTION: Addition of carbon black in Polythene for pipes and other products for outdoor application acts as UV radiation screening agent. About 2.0 to 3.0% carbon black gives optimum life and performance to product Determination of Carbon black content is based on heating of polymer at about 5000C in inert atmosphere. At this temp. polymer molecules volatilize break down into a gas , and leaves the residue as carbon black and other fillers. Further heating of residue in the air i.e in muffle furnace at about 4500C separates carbon from fillers EQUIPMENT: Carbon black content tester, analytical weighing balance, Muffle furnace, test boat etc is used. TEST SAMPLE: About 1 gm of sample cut into small pieces are used Corporate Training & Planning

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CARBON BLACK CONTENT PROCEDURE: About 1g of sample is taken and weighed in analytical balance. Test temperature of oC is set .Sample is placed in the combustion tube. A stopper carrying thermocouple and tube for admission of nitrogen gas is inserted from one end of combustion tube. Nitrogen gas is passed in combustion tube at the specified rate. The furnace is maintained at oC temperature for about 10 minutes. During this period polymer voilatise. The boat is removed from tube and placed in a desiccators and cooled for minutes. The content is weighed accurately. Subsequently, the residue is heated in air/muffle furnace at about 450oC. It is then cooled until to room temp. Weight is taken recorded as W2 . Corporate Training & Planning

CALCULATION : The Carbon Black Content is calculated as : % By mass = Weight of Carbon Black Weight of material CARBON BLACK DISPERSION : Carbon black added to the Polyethylene material for protecting polythene from UV radiation and improves the performance provided the distribution of Carbon black in the material is uniform . Carbon black is a brittle material so its non uniform distribution can cause localized brittleness, weakening & inadequate protection UV radiation to material. Carbon black dispersion test can reveal whether distribution is satisfactory or not EQUIPMENT: Hot plate, microscope with adequate magnification, glass slide etc Corporate Training & Planning

PROCEDURE: Carbon black dispersion is determined as following: First test slide is prepare by heating of few gm of materials on hot plate A hot plate is heated at about 170oC to 210oC, two clean glass slides are placed on the hot Plate. About 5 mg is placed over the slides and heated. A piece of metal shim is placed on hot micro slide. Uniform pressure is applied for about 2 minutes. The micro slides are removed from hot plate and allowed to cool to room temperature. Slides are examined in microscope at magnification of Image obtained microscope is compared with the reference photo micrograph in respect of number and size of agglomerate. The uniformity of background is recorded. The dispersion of carbon black shall be satisfactory in comparison to photomicrograph. Corporate Training & Planning

INTRODUCTION: ABS is highly susceptible to residual stress. During processing of ABS pipes and other product residual stress is commonly introduced. This test is carried out for evaluation of the residual stresses in ABS pipes as these stresses can cause localized weakening of the product and failure during its end use application PROCEDURE: Specimen from pipe is cut in any suitable size and immersed into reagent grade glacial acetic acid for 30 seconds. Immediately after the immersion, the sample is removed, rinsed in running water and dried. The specimen is examined for cracking. The above procedure is repeated for specimen for 2 minutes or for the same specimen for an additional 90 seconds. Again, the specimen is examined for cracks. The time taken to develop cracks and the degree of cracking indicate the magnitude of residual stress in the specimen. Corporate Training & Planning

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ENVIRONMENTAL STRESS CRACKING RESISTANCE TEST ( IRRIGATION LATERAL AS IS : : 1989)  INTRODUCTION : Environmental stress cracking resistance is a particular kind of chemical attack which must be avoided with polyethylene pipes. Certain chemical causes of premature failure of some polyethylene under the stress in the accelerated environmental   ESCR of polyethylene lateral is important when pipes are used in the filled under pressure they undergo various compressive bending stress and possibility of premature failure is increased in accelerated environment of heats and chemicals . Thus ESCR is determining factor in these applications. Corporate Training & Planning

Fig. Test specimen for ESCR test Corporate Training & Planning

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ENVIRONMENTAL STRESS CRACKING RESISTANCE TEST ( IRRIGATION LATERAL AS IS : : 1989) PROCEDURE: Take test piece of approximately length of 20 times of the diameter of pipe, Bend sharply at both ends to form two U – bends, in two different planes perpendicular to each other as shown in figure. Secured bend tightly to maintain in deformed shape throughout the test. Coat each bend with surface – active agent (Igepal CO630) by dipping and place in an oven for 30 minutes at 50 ± 3oC Inspect each bend for any visible crack on both sides. Corporate Training & Planning

Objective : Determination of Vicat softening temperature of thermoplastic material using method A or method B. Method A uses a load of 1.0 kg. and method B uses a load of 5.0 kg. Principle : Determination of temperature at which a standard indentor penetrates 1mm in to the surface of plastic test specimen under one of the load as given above. During the test temperature is raised at uniform rate either at 50  50C / hrs. or 1200C  120 C/hrs. The temperature at 1 mm penetration is quoted as Vicat softening temperature (VST) in 0C Definition : Vicat softening temperature is the temperature at which a flat ended needle of 1 mm2 circular section will penetrate a thermoplastic specimen to a depth of 2 mm under a specified load using a selected uniform rate of temperature rise. The two standard permissible rate of rise of temperature are 50  500C/hr. and 120  120C/hrs. Significance : This test is useful for quality control of development and characterisation of material. Vicat softening data obtained from this test is used for comparing heat softening qualities of thermoplastic materials. Safety : Safety gloves should be used. Corporate Training & Planning

APPARATUS Heat distortion and vicat softening apparatus consisting. Immersion bath. Heat transfer liquid (such as silicon oils, glycerine ethylene glycol etc.) Support or stand for specimen and dial range. Dial gange (0-25mm) for measuring of 1 mm depth of penetration to accuracy of 0.01mm. Temperature indication device (such as thermometer) Weight : (1.0 k.g. or 5.0 k.g.) depending on test method. Flat ended needle of 1 mm2 circular cross section. TEST SPECIMEN : Specimen of minimum 12 mm wide and 3.0 to 6 mm thick shall be used. It is surfaces shall be flat parallel and free form flash. Place the specimen on specimen support. Position the flat needle in such a way that needle rest in the sample in centre. Immerge the specimen support assembly with sample in immersion bath. Set the micrometer to zero. Corporate Training & Planning

PROCEDURE Place the weight to load carrying plate on the spindle which is fitted with flat needle so that total load on test specimen is 1.0 k.g. for method A of and 5.0 kg. for method B. Increase temperature of oil bath at the rate of 500  50C/hr (Rat A) or 1200 120C/hr Observe the dial gange for penetration of needle in the specimen. Note the temperature of oil bath at which indenting tip has penetrated into test specimen by 1.0 mm and record it as vicat softening temperature (VST). Line diagram to be drawn. Corporate Training & Planning

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INTRODUCTION: Plastic films are used for packaging, construction and other industrial applications. It has to perform various functions of package, fabrications, product protections, containment & appearance. Hence it require a set of properties. Properties of films are broadly classified as : Physical , Mechanical , Chemical, Optical and Thermal and other such as mach inability ,printability etc. Corporate Training & Planning

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FACTORS INFLUENCING Following factors influence the properties of Plastic films : Chemical Composition of base polymers Compounding ingredients such as additives, colourants. Method of manufacturing of film(e.g. Blown Film,Cast Film, TQP processes etc.) Post treatments, coating and lamination Commonly used materials for film are :- Polyolefin (LDPE,LLDPE,HDPE & PP) EVA PVC, PVDC & PVA PS Polyamide, Polyester &Polycarbonate Cellophane etc. Corporate Training & Planning

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PROPERTIES OF FILMS The properties of plastic films can be classified as Physical Properties Mechanical Properties Chemical Properties Optical Properties Thermal Properties Printability Sealability Corporate Training & Planning

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TESTS ON PLASTIC FILMS Broadly tests on plastic films and laminates can be classified as Properties Concerned with : Strength: Tensile strength, Stiffness, Burst strength, Tear strength , Impact strength, Flex Resistance Transmission: Water vapour Permeability Odour Permeability Light Transmission – See-through Clarity or Transparency Gloss Haze Surface: Friction, Mar Resistance ,Blocking ,Electrostatic Charge. Heat Salability Printability & Print Adhesion etc. Corporate Training & Planning

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TESTS ON PLASTIC FILMS Other Properties are : Density Thickness Dimensional Stability Orientation and Shrinkage Melt Flow Index Light Resistance Chemical Resistance Solvent Resistance Toxicity Corporate Training & Planning

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TESTS ON PLASTIC FILMS TENSILE STRENGTH: Tensile strength is an important property for the quality control of plastic films. Used for differentiating different types of film based on strength. Used to ascertain the anisotropicity in a film i.e. Different strength in different direction (Transverse & Machine direction) Elongation is useful as a measure of film’s ability to stretch. Corporate Training & Planning

Film should have enough tensile strength to withstand the load. Yield strength is important in handling on printing & lamination equipment. To identify the elongation of film with respect to tensile strength. Corporate Training & Planning

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BURST STRENGTH DEFINITION Resistance offered by film to a steady increasing pressure applied at right angle to its surface. Pressure at the moment of failure of film is taken as the Burst strength. SIGNIFICANCE OF BURST STRENGTH Measures the capacity of the film to absorb energy at the time of failure. Indicates the energy absorbing capacity of film. Brittle film which can absorb small amount of energy before breaking have low burst strength. EQUIPMENT : A film burst strength tester is used. It consists of sample clamping device, pressure gauge and pressure releasing device, air compressor etc. Corporate Training & Planning

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BURST STRENGTH PROCEDURE: Test pressure is normally applied by compressed air. The liquid medium may also be used. When liquid medium is used, the pressure is transmitted via a rubber diaphragm. The film to be tested is clamp in form of disc. The compressed air or liquid pressure is released through pressure releasing device. The pressure at the moment of failure of film of noted from the pressure gauge. Factors affecting burst strength: Following factor affect the burst strength of film. Speed at which pressure is applied : At low rate of pressure application burst strength is high. Diameter of sample in clamp disc: Smaller the diameter of clamp disc, higher is the burst pressure. Corporate Training & Planning

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TEAR STRENGTH Definition Tear strength is defined as the energy required to propagate a tear through a specified length of film that has already been initiated in sample by small nick with a razor blade. Tear resistance measures the tear initiation and tear propagation energy. Generally tear of brittle film is measured as the maximum tear initiation force whereas for tear propagation is important in tough film. Tear strength is measured as Tear initiation and Tear propagation. Significance Tear strength measures the resistance to tearing and it may also used to illustrate the anisotropy of the film. Tear resistance measures the tear initiation and tear propagation energy of the plastics film. Tear of brittle film is measured as the maximum tear initiation force Tear propagation is important in tough film. Corporate Training & Planning

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TEAR STRENGTH Test Methods of Tear Test : Following methods are commonly used for measuring tear strength: Elemendorf of tear test Trouser tear Tongue Tear Initial tear resistance film and sheeting This method measures the energy required to propagate through a specified length of film. Equipment Elemendorf tear tester consisting of two grips set side by side with small separation, Test sample template, Razor blade, Thickness measuring devices. One grip is stationary and fixed with base of m/c whereas another is movable grip and it is mounted on the pendulum of m/c. Corporate Training & Planning

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TEAR STRENGTH PROCEDURE Sample from the film is cut using sample template and Razor blade and measure the thickness of specimen by micrometer. Sample is clamped between two grips and a slit of standard dimension is introduced centrally into the film using a razor blade. Pendulum is released to swings down and tears the samples along a continuation of the slit. The energy required to complete the tear is measured on a scale attached with pendulum by means of a pointer carried by the pendulum on it’s return swing. Corporate Training & Planning

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TEAR STRENGTH Trouser & tongue tear test Trouser & tongue tear test is determined by using the tensile testing machine. In this tear propagation is measured as the force necessary to keep the moving at a fixed speed. The stress – strain curves obtained is analyzed in different ways depending upon their shape. The geometry of the test piece is such that a concentration is produced in the region of the right and the tear initiates at this point, The maximum stress during the tearing process is recorded as the tear initiation strengths. The various types of samples and methods used for tear tests are as under. Corporate Training & Planning

82 TEAR STRENGTH (a) Trouser Tear test (b) Torque tear test
Test specimen as per ASTM D 1938 Corporate Training & Planning

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TEAR STRENGTH FACTORS AFFECTING TEAR STRENGTH Generally films are anisotropy so the strength properties of film are not same in all the direction. Therefore tear strength of anisotropy film depends upon the direction of orientation. Therefore tear strength widely vary according to direction of orientation of film. Tear strength in the direction of orientation is less than to transverse direction. Corporate Training & Planning

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IMPACT STRENGTH INTRODUCTION: It is the ability of film to withstand sudden sock loading. This property measures the ability of a material to absorb energy in a very short period of time and it is closely related to toughness of the film. Impact resistance is also related to brittleness of film. Brittleness denotes the lack of ductility, poor flexing properties etc. DEFINITION: Impact strength of the film is defined as the amount of dart weight for a given height of fall at which 50% of the specimen will fail. It is calculated by weight at which it causes 50% failure of film multiplied with drop height Impact strength is measured by various methods such as Dart impact test, Pendulum impact etc. The most commonly used method for measurement of Impact strength is falling dart impact test. Corporate Training & Planning

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IMPACT TEST FALLING DART IMPACT TEST: Impact strength of the film is defined as the amount of dart weight for a given height of fall at which 50 % of the specimen will fail. It is calculated by weight at which it causes 50 % failure of film multiplied with drop height EQUIPMENT: Dart impact tester consisting of hemispherical striking head fitted with a shaft to which removable weight can be added / removed, to obtain required range of test energy. Circular section of film is clamped horizontally at it’s periphery and dart is dropped from a specified constant height on film sample at the center. Following two methods are employed in Dart impact testing. ( a ) Stair case method ( b ) Probit method Corporate Training & Planning

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IMPACT TEST PROCEDURE: Clamp the specimen horizontally at it’s periphery and take the dart Initially few specimens are taken in trial run to obtain indication of impact energy at which about 50 % failure will occur. The first specimen is tested at arbitrary level of dart weight at a given height of fall and subsequent specimens are tested at half or double of this dart weight till some specimens fracture and some withstand the impact Corporate Training & Planning

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IMPACT TEST Corporate Training & Planning

In this method further 20 specimens are tested using same height as used in trial run Weight of dart is increased or decreased about one tenth of dart weight found in trial run. When a specimen fractures, next specimen is tested at lower dart and when does not fracture the next specimen is tested at higher dart weight The Impact strength is defined as the level of dart weight for a given height of fall at which 50 % of specimen will fail. It is the mean of weight of all the values used in the test run. ALTERNATE METHOD In this method impact tester is additionally fitted with two photoelectric cells just below the test sample and the dart impact energy is adjusted in such a way that all the test sample rupture. Original potential energy of dart is above the sample is obtained from it’s mass and height i.e. by mgh. While residual kinetic energy after impact is calculated using formula of ½ mv2 . The Impact energy absorbed is found as Impact strength = Potential energy - Residual kinetic energy of film. Corporate Training & Planning

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IMPACT TEST PROBIT METHOD This method assesses impact strength of film by determining the percentage failures in a given number of specimens with different dart weights. Dart weight is selected which will fracture at least one of a group of ten specimens. The actual number of failures in ten trials is recorded. The dart weight is then changed by uniform increments and ten samples are tested at each dart weight. The number of failure at each weight is recorded. The data are plotted on probability graph paper, the dart weights on the linear scale and the percentage of failures on the probability scale. The Impact strength is read as the dart weight at which 50% of specimen fails. The impact failure weight or impact resistance expressed in grams. The Impact strength is read as the dart weight at which 50% if the specimen will fail. Corporate Training & Planning

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IMPACT TEST PENDULUM METHOD In this method impact strength of film is measured by pendulum instead of falling dart. Film is clamped vertically and struck by a pendulum swung from a known height. The residual energy of the pendulum after it has ruptured the film, is measured by a pointer on calibrated scale of by an electric timer activated by a pair of photoelectric cells. The loss in energy is a measure of impact strength of the film. Corporate Training & Planning

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IMPACT TEST IMPACT TEST OF FINISHED BAG The impact test of finished bag is done by bag drop test. The bags to be tested are filled with specified weight of sand or other suitable material and sealed. Thus filled and sealed bags are dropped from a test height on to a right angle at smooth surface. The bags is examined to see if the failure was in the seal or in the film. FACTORS AFFECTING IMPACT STRENGTH OF FILM Rate of Impact load applied : Impact strength reduces at height rate of impact. Size of hemispherical head /striking head : Smaller hemispherical diameter of dart lower is the impact strength. TEST TEMPERATURE : At higher test temp the Impact strength shown by film are higher as the molecular mobility of polymer at higher temperature gets increased. Corporate Training & Planning

INTRODUCTION: Various properties of the film are seriously affected by repeated folding . For example tensile properties are reduced, permeability to gases, water vapor may be increased, optical properties may be affect. DEFINITION: Flex resistance is defined is the Resistance to repeated flexure or creasing measured by repeatedly folding the film backward and forward at a given rate. The number of cycles to cause the failure is called as flex resistance. Higher the number of cycle of failure higher is the flex resistance. Corporate Training & Planning

TEST PROCEDURE Flex resistance is measured by Schopper folding endurance tester. The step by step procedure is as below: Film strip of 15 mm x 100 mm are cut. Strip ends are clamped between the clamps in such a way that constant tension in the film is maintained. Scotted metal strip is fitted over mid point of sample. Sample folded by electric driven motor is back and forward at the rate of 120 double fold per minutes. The number of double fold at the time of failure of film is recorded as flex resistances Corporate Training & Planning

The tough and flexible film may not fail even after large number of repeated flexing so higher thickness of film has to be taken till the failure is observed. Alternatively flex resistance of tough and flexible film is also measured by subjecting the film to a number of cycles in test equipment and relevant test results are compared with unceased film. FACTOR AFFECTING : Folding endurance of film depend upon the material of the film because the cheval difference in composition of materials. The thickness of film and rate of folding of film per minutes affect the result. Corporate Training & Planning

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TROUSER TEAR TEST Corporate Training & Planning

GAS PERMEABILITY INTRODUCTION One of the prime functions of a packaging film is to act as a barrier to gases and vapors. Biscuits, for example, need to be kept in dry, while conversely; cigarettes and tobacco need to be protected from moisture loss. Fresh produce needs to be able to lose carbon dioxide and pick up oxygen, while fatty food may go rancid if oxygen is not kept out. Many foods are packed in a vacuum and a good barrier is essential. NEED OF PERMEABILITY TEST To maintain the film as a good barrier to gases & vapors. To distinguish the packaging film as per the application (e.g. Biscuits need to be kept dry, while conversely, cigarettes and tobacco need to be protected from moisture loss). Corporate Training & Planning

DEFINITION (i) Gas Transmission Rate The Gas Transmission Rate (GTR) is defined as the volume of gas that passes through a sample of unit area under unit pressure differential. The rate being determined after the slope of the transmitted volume – time curve has become constant. The temperature and specimen thickness must also be given as an integral part of the GTR. (ii) Permeability Co – efficient The permeability Co – efficient represents the fundamental property and is independent of the geometry of the test sample. It is the product of the solubility of the gas in the film and the diffusion rate of the gas though the film. Gas transmission rate is usually expression in cc(at 0C and 76 mm Hg) per sq.m 24 hr. atm. Corporate Training & Planning

PERMEATION The mechanism by which a gas or vapor can pass from one side of a plastic film to another by a process of solution (or absorption ) and diffusion is known as permeation. It is a compound process. In very thin (i.e. porous) films the gas or vapor can flow through the holes. The quantity of gas(Q) passing through the film is Directly proportional to: The difference in gas pressure on either side of the film ( P1 – P2 ) The time during which the permeation has been occurring (t) The exposed area A) Inversely proportional to: The thickness of the film(X) The Mathematical expression is define as:Q=[PAt(p1-p2)/X] Where ‘P’ is the permeability constant. Corporate Training & Planning

Thus it may be written as Q = At ( P1 – P2 ) X Where : Q = quantity of gas which passes through the film; A = The surface area in contact with the gas; t = time; ( P1 – P2 ) = partial pressure differential; X = thickness of plastic This expression can also be put in the form of an equation, thus Q = PA t ( P1 – P2 ) X Where P is a constant for a specific combination of gas and plastic at a given temperature. The factor P is known as the permeability factor ( or ‘P – factor’) permeability Co – efficient or permeability constant. Corporate Training & Planning

Permeability of plastics films by gases is described as the volumetric rate of transmission of the gas It is dependent on, both the nature of the plastics material and of the gas. Physical nature of the film, its density, degree of crystallinity thickness of the film etc affect the transmission rate. Size and mobility of the gas molecules, play an important role in the rate of transmission of gas. Interaction of gas and polymer film may have significant complex interaction which affect transmission rate. Corporate Training & Planning

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Permeability of plastics films by gases is described as the volumetric rate of transmission of the gas It is dependent on, both the nature of the plastics material and of the gas. Physical nature of the film, its density, degree of crystallinity thickness of the film etc affect the transmission rate. Size and mobility of the gas molecules, play an important role in the rate of transmission of gas. Interaction of gas and polymer film may have significant complex interaction which affect transmission rate. Corporate Training & Planning

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EQUIPMENT Gas Permeability Tester, Consisting of Vacuum pump, Micro Meter and Stop Watch, Desiccators, The typical Equipment is shown in figure MATERIAL : Dry and pure test gas , Mercury, Desiccators, Cacl2 TEST SPECIMEN : Sample, free from wrinkles, creases, pinholes and other imperfections having uniform Thickness shall be used. PROCEDURE: Equipment is prepared by filling the required quantity of mercury Specimens from the film is cut in the size to fit the test cell. Thickness of the film sample is measured and conditioned in the desiccators. The test specimen is placed in the test cell between filter papers for ensuring the uniform gas distribution Corporate Training & Planning

The manometer of the permeability tester is evacuated with the help of vacuum pump, Equipment is connected with the test gas from the upper half of the specimen where as lower half is maintained at vacuum. The transmission of the gas through the film w.r.t the time is recorded in the terms of the fall of mercury in the manometer due to increasing of the pressure . The reading is taken and suitable graph is plotted. GTR is calculated by using following formula T.R = (237 x PV) (24 x 104) A x T x P Where T.R is ml per m2 / 24 hrs per atmosphere pressure difference P= rate of pressure changes in capillary in an Hg per hour. Corporate Training & Planning

ODOUR PERMEABILITY Odour permeability is used to compare the efficiency of several films as odour barriers, to manufacture pouches with each film. Odiferous material filled with pouches and then placed in separate clean glass bottles and sealed by clamping with aluminum foil. Minimum time for an odour appeared in the bottle measured. Test depends upon the type of odiferous material used. There is no standard tests for the measurement of odour permeability. Corporate Training & Planning

DEFINITION The water vapor transmission rate, WVTR or MVTR, is the flow rate of water through a unit area of film after the steady state has been reached(unit- gm / 24 sq u.m). Film used for packing foodstuffs usually have a low water vapor permeability. The permeability is measured by method in which the test film is fastened over the month of a cup containing either a desiccant or water. EQUIPMENT Environmental chamber with temp. and humidity control, Desiccant, Petridis, Cacl2, Analytical weighing balance. The apparatus is shown in figure. PROCEDURE: Take a circular mouth cup, and fill water or desiccant in the cup. Cut the film sample approximately equal to the internal diameter of the cup and seal at its mouth Corporate Training & Planning

Set the test temperature and humidity in the chamber Take the initial weight of the cup with sample with the desiccant on the analytical balance. Place the sealed cup containing desiccant or water in the controlled atmosphere for specified temperature and humidity. After a specified period the sample is removed from the chamber and again it’s weight is taken on the balance. The weight gain or loss measured as a rate of water vapor transmission through the film can be calculated. ALTERNATE METHOD Another method is of measuring water vapor transmission rate is Dish method as per BS – The equipment set-up of the same is shown in the fig. The water vapor permeability may also be measured by enclosing the desiccant in a sachet made from the film itself instead of using a dish Corporate Training & Planning

109 WATER VAPOUR PERMEABILITY Fig. Apparatus for Water Vapor Transmission
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LIGHT TRANSMISSION DEFINITION: Light transmission through the film is one of the important properties on the packaging application. It allows to view the object through the packaging material. It is the ratio of the light intensity measured with the film to that obtained without it. Light transmission is measured by means of a photoelectric cell. The intensity of a light source is measured by the cell, both with and without the inter position of the film samples. Other important optical properties of films are: Haze, Gloss and clarity. Detail about the equipment and test procedure of measurement is described in the Optical Properties Corporate Training & Planning

DEFINITION : The ratio of the intensity of light to the intensity of the incident beam is a measure of see – through clarity. It refers to the capability of seeing objects through a film without loss of detail caused by blurring or distortion. Narrow angle scatter correlates with see – through clarity. The test measures the light transmitted by a film within a cone of semi – angle of three minutes about the normal to the specimen. Detail about the equipment and test procedure of measurement is described in the Optical Properties Corporate Training & Planning

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HAZE DEFINITION Haze is the property often referred to as cloudy appearance. Haze is defined as the percentage of light which is passing through a specimen, deviates by more than 2.5 on average from an incident parallel beam. It is caused by random scatter of incident light upon film. This is measured using a haze – meter. The ratio of the scattered light (T2) of the photo cell to the incident light (T1) is a measure of haze. i.e % Haze = (T2/T1) x 100 Detail about the equipment and test procedure of measurement is described in the Optical Properties Corporate Training & Planning

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GLOSS DEFINITION Gloss refers to the shining appearance of a plastic film It is defined as the ability of a surface to reflect light regularly. Secular surfaces gloss of the film is measured as the portion of light reflected from the film at an angle of 45o. This is compared with a perfect mirror which is given a value of 100. The maximum value of gloss for low density polyethylene is about 9.9 %. Detail about the equipment and test procedure of measurement is described in the Optical Properties Corporate Training & Planning

FRICTION: The resisting force that arises when a surface of one substance slides over an adjoining surface of it-self or another substance. SLIP : Lubricity of two surfaces sliding in contact with each other is called slip. High co – efficient of friction denotes low slip and low co – efficient of friction denotes high slip. Co – efficient of friction :- It is defined as the ratio of frictional force to the force ( usually gravitational ) acting perpendicular to the two surfaces in contact. Two types of Co – efficient of friction i.e Static Co – efficient of friction ( μs ) Kinetic or dynamic or sliding Co – efficient of friction ( μ k ) Corporate Training & Planning

It is related to the force measured to begin the movement of the surface relative to each other. It is defined as the ratio of force required to just begin the movement to the force acting perpendicular to the surface. μs = Force required to begin movement Force acting perpendicular to surface Corporate Training & Planning

It is related to the force measured for sustaining the movement . It is defined as the ratio of the force required to sustain or maintain movement to the force acting perpendicular to surface. μk = Average force required to sustain movement Force acting perpendicular to surface Generally the force required to begin movement is more than force required for sustaining movement. Therefore static Co – efficient of friction is generally higher of friction than Kinetic Co – efficient of frictions Corporate Training & Planning

The frictional properties of films are important in winding while manufacturing of film, during it’s printing,wrapping and in the form of finished bags, sacks or over wraps etc. Good roll formation depends upon correct level of friction of film. Too much slip may cause telescoping during of rolling,handing and transportation. Too little can cause buckling on roll. The inadequate slip may cause seizure of film during printing. Corporate Training & Planning

Co – efficient of friction is measured by following two methods. Inclined plane method. Method based on ASTMD 1894 Corporate Training & Planning

(A) INCLINED PLANE METHOD STATIC CO-EFFICIENT OF FRICTION: The inclined plane method is simplest method of measuring Co – efficient of friction. Under this method surface of inclined plane is covered by a sample of film and weight is placed on the plane The angle of the plane is increased slowly until weight just start to move. The angle at which it starts moving is noted. This angle is called repose angle. It is denoted by Q1. DYNAMIC CO-EFFICIENT OF FRICTION: For measuring dynamic Co – efficient of friction the angle of plane at which weight moves easily is gradually reduced until weight comes to rest. The angle of the plane at this stage is noted as Q2. The Tan Q1 and Tan Q2 are the static and dynamic Co – efficient of friction Corporate Training & Planning

(B) METHOD BASED ON ASTM D 1894 The apparatus based on this method consist of metal block ( sled ) of about 63.5 , square and 6mm thick . Sled is wrapped with rubber sheet to provide wrinkle free surface. The total weight of sled is 200 ± 5g. It is wrapped and tape of with film. A table of wood / plastics / metal sheet of Apex 150 mm X 300 mm x 1 mm is fitted with smooth and flat covering glass on the upper surface to provide support for the specimen. This table with sled is motor driven at the rate of 150 mm / min. The further detail of the equipment and procedure is described in the chapter Mechanical Properties.

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BLOCKING DEFINITION: The tendency of two adjacent layers of films to stick together when stacked under pressure is called blocking. It is an adhesion between touching layers of plastic film. The blocking develops under variety of condition of temperature and pressure. Blocking may also arise from processing, under usage or in storage. The blocking in film may occur when film surfaces are extremely smooth or allowing intimate contact of film surfaces under complete exclusion of air. It may also occur under fusion of the surfaces under heat and pressure. The force required to separate two layers of blocked film when the force is applied perpendicularly to surface determines the degree of blocking. Corporate Training & Planning

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BLOCKING BLOCKING FORCE: It is the average force per unit width of blocked surface required to separate two layers of plastic film one from another by a rod of 6.35 mm diameter at uniform rate of 125 mm / min. This force is expressed in grams per centimeter of width. TEST SPECIMEN Test specimens of film consists two blocked layers cut in rectangular shape. The size of specimen is taken as 250 – 300 mm long and 200 – 250 mm wide. EQUIPMENT An universal testing m/c, a metal fixure and a rod of 6.35 mm diameter is used for separating the blocked film Corporate Training & Planning

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BLOCKING PROCEDURE: Metal fixure is attached with moving jaw of Universal Testing M/C. Specimen to be tested is clamped in fixed jaw as shown in figure. Machine is started and blocked surfaces are separated at rate of about 125 mm / min. As the jaw moves it draws the frame and rod downward. The motions of rod cause layers of film separate. The force required to separate the layers of film apart is recorded. This process continues until layers of film are completely separated. The Actual blocking force is determined from best average load line. The average load in grams is divided by specimen width in mm. It is expressed in gmf / mm Corporate Training & Planning

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BLOCKING TEST Corporate Training & Planning

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BLOCKING TEST FACTORS AFFECTING: The following factor affects the blocking of film. Thickness of the film: Low thickness of film has higher tendency of blocking Static charges, Surface treatment, Printing, Pre – treatment, Storage condition etc also affect the blocking. Long storage duration increases the tendency of blocking. Corporate Training & Planning

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BLOCKING TEST HEAT SEALABILITY Heat sealability of the packaging film is one of the most important properties when considering its use for wrapping and bag making. Therefore the integrity of the seal has the tremendous, important in ultimate package. TEST METHOD: The following two methods are commonly used for testing of heat salability of film. (A) Dynamic method (B) Static method In above test methods two layers of film are sealed under heat and pressure using suitable heat sealing device. A 25 mm wide strip is cut through the heat seal. This test sample is used for testing by both methods. Corporate Training & Planning

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BLOCKING TEST (A) DYNAMIC METHOD Under dynamic test method a sensitive tensile testing m/c is used. The two free ends of film strip are clamed in machine grip and pulled a part. The force required to peel apart the two pieces is measured. (B) STATIC METHOD In static method one end of filmstrip is clamped and hung from a frame and other end is attached to a dead weight. The seal are examined at a regular interval of time for any sign of failure. The weight and duration of load, which was hung, is taken upto failure and recorded. The heat salability of the film is affected by sealing temperature and rate of heat transfer of sealing and dwell time. MAR RESISTANCE It may be defined as the resistance of the surface to abrasive action of abrasive particles. The following three methods are used for measuring Mar resistance. Corporate Training & Planning

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BLOCKING TEST METHOD I: This method is based on AST MD – 1044 – 76. The surface of the specimen is subjected to an abrasive action and then the light scattering properties of the abraded area are determined and compared to those of the original unmarred sample. METHOD II: This method is based on ASTMD– 673 the film surface is abraded by dropping abrasive particles on to the film from a fixed height. The gloss of the marred area is measured and Compared to the unabraded film to determine the mar resistance. METHOD III: This method is based on ASTM D – 1242 – 75 surface of film is abraded in a standard way and the volume of material lost by the specimen due to this abrasive action is determined. The loss in volume is taken as a measure of the abrasion resistance. PRINTABILITY AND PRINT ADHESION Printability depends directly on film treatment and while its print adhesion depends on both ink and film. Corporate Training & Planning

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BLOCKING TEST PRINTABILITY A method for measuring the printability or degree of treatment of film measures, the force required to peel a strip of pressure sensitive tape from a section of film. The tape is applied to the film and the assembly is clamped together for a standard time under standard pressure. Any suitable machine measures peeling force with an autographic recording device. PRINT ADHESION The Permanence of the printing on the film is measured by subjecting the printed film to an abrasion test. For testing, the Printed film is mounted in glass plate and abraded forwards and backwards against metal peg covered with a strip of standard fabric. The no of cycles required to produce visible damage to the print is recorded as print adhesion. Corporate Training & Planning

INTRODUCTION: Dimensional stability is a desirable property in film conversion process particularly in printing. The small changes in film dimension while passing through printing process may lead to serious printing problem. PROCEDURE: Dimensional stability of film is carried out by cutting film strips in both machine and transverse directions. Film is subjected it to varying conditions and noted the percentage change in dimensions. The test conditions are kept very close to the conditions likely to be encountered during conversion or end – use process. The maximum shrinkage is measured in the case of heat shrink films. This is determined by immersing the marked film samples for 5 minutes in water or in silicones oil at 1000 C. Corporate Training & Planning

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LIGHT RESISTANCE INTRODUCTION: Plastic films exposed to sunlight for long period properties and performance of the film is affected as UV radiation raises the surface of temperature of film. UV radiation and heat causes the oxidation reaction, evaporation of plasticizers, polymer bond, chain scission etc This leads to brittlement of film, color change, loss of clarity of film surface, imperfections, and reduction of strength properties etc. PROCEDURE: This test is carried out by exposing the film samples in weather-O- meter or UV Chamber. In weather-O-meter light of suitable wavelength or combination of wavelength is artificially created with the help of UV lamp fitted in the chamber and sample is exposed to UV light for a given time. The film samples are taken out and test for various parameter such as tensile strength, % elongation, impact strength and various optical properties etc. is carried out . The result obtained is compared with the result of original unexposed samples. Corporate Training & Planning

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CHEMICAL RESISTANCE INTRODUCTION The effect of chemicals on a packaging film is an important factor when assessing its suitability for packaging a particular product. Under certain circumstances, it may also be important from an environmental point of view. Therefore measurement of chemical resistance is an important property of films. DEFINITION Chemical resistance involves the subjecting of film sample to the chemical under test. Test sample are immersed in chemical under a specified condition. The change in appearance and in property such as tensile strength, transmission properties and other are co – related with the chemical resistance of the film. Corporate Training & Planning

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HEAT SHRINKAGE DEFINITION Heat shrinkage is defined as the dimensional changes of film due to heating and subsequent cooling. Some products are packed in the film package in the hot condition. This raises the temperature of film material, and on cooling stress reliving takes places. This causes the dimensional changes. PROCEDURE: Heat shrinkage is determined by immersing marked film sample in water or silicon oil at 100oC for five minutes and measuring the dimensional changes in with respect to original marking. It is expressed in percentage. Corporate Training & Planning

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CONTAINER TESTING Corporate Training & Planning

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PURPOSE OF CONTAINERS Plastics containers are commonly used To check suitability of container for packaging of food-stuff, liquid, semi-solid and solid materials Transportation, handling, storage and sales of of materials Provide protection during conservation Preventing from contaminations and maintaining hygienic conditions Quality control of the containers Corporate Training & Planning

Following materials are used packaging of different kinds of materials Polyethylene(HDPE,LDPE,LLDPE) Polypropylene(PP) Polystyrene(PS) Polyvinyl chloride(PC) Thermoplastic polyester (PET) Corporate Training & Planning

Easy Process ability Good Chemical Resistance Good Impact strength. Inertness Heat stability Good Environmental Stress Cracking Resistance Corporate Training & Planning

Following tests are most commonly carried out on containers Stacking Test Drop Impact Test Leakage Test Closure leakage test Vibration Leakage Air Pressure Leakage Handle pull test Environmental-Stress cracking Resistance Transparency Overall Migration Test Ink adhesion for printed containers Product Resistance of printed containers Water potability Test Corporate Training & Planning

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STACK TEST DEFINITION : Stacking is subjecting the plastics containers to a specified load based on the the capacity of the containers for a specified period of time. Significance of the test : To check the ability of the filled containers to withstand compression loads when the containers are stacked over another set of containers during the transportation and storage. When the filled containers the setup If the stiffness and strength of container is inadequate the compressive load of filled container may permanently deform or buckle the container and content may leak Corporate Training & Planning

140 STACK TEST PROCEDURE Block of four containers are taken and used in a single test. Fill the containers with water to their nominal capacity close with their usual closure and heat seal at the mouth. Arrange four containers on a flat level surface without any outer support. Apply a top load on the container for 24 hrs in such a way that it is evenly distributed on the containers. Superimposed load for different sizes of containers shall be as under Examined the containers after 24 hrs of the test for any leakage, crack and permanent buckling etc. The container should not show any leakage, crack and permanent buckling etc. Container’s Nominal capacity (Kg) Stack load on the four containers (N) 1.0 400 2.0 600 5.0 800 10.0 1200 15.0 1600 Corporate Training & Planning

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DROP IMPACT TEST This test measures the ability of the containers to withstand damage to the container and packing material caused by sudden shock induced in accidental dropping, rough handling, transportation etc. This test also provides useful information in improving the design of the containers. The test is carried out by dropping the preconditioned sample freely from a specified height which is filled with suitable material in it. The sample strikes the base in a predetermined position. The sample should resist the impact. Corporate Training & Planning

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TEST PROCEDURE Take 6 nos. of containers and divide in to two sets and designate Set – I & Set – II. Fill the containers with water to their nominal capacity at standard conditions Close the containers with there usual closure and heat sealed to its mouth. Drop the containers of set – I under free fall condition squarely on their base on the rigid flat horizontal surface from the specified height. Drop the containers of set – II under free fall condition on their side on to a rigid flat horizontal surface from the specified height. Specified drop height for different capacity of containers varies from 0.5 m to 1.2 m Checked the each container for any ruptured , leakage from the wall or closure. There shall be no ruptured, leakage from the wall or closure Corporate Training & Planning

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LEAKAGE TEST Leakage may occur due to the top load of the packed product, transportation vibration or leakage because of internal pressure developed inside container. Leakage test is carried out to check the defects in the closure system of the container. Generally three types of leakage test are conducted on plastics containers i)                     Closure Leakage ii)                   Vibration Leakage iii)                  Air Pressure Leakage Test Air pressure leakage test is carried out by maintaining the specified pressure inside container and detecting any leakage with water or soap solution. Corporate Training & Planning

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I. CLOSURE LEAKAGE TEST Closure leakage test is carried out by placing filled container in inverted position at a specified condition. PROCEDURE : Take a container and fill it to it’s nominal capacity with colored water or material to be packed at specified condition, Close the container with it’s usual closure Keep the container in an inverted position on a white blotting paper without any external support for a specified period. Examine the container for any leakage for any visible stains on the blotting paper. The container should not show any leakage or stain on blotting paper. Corporate Training & Planning

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VIBRATION LEAKAGE Vibration leakage test is carried out on filled containers by subjecting a specified vibrational frequency for a specified time period. PROCEDURE Take containers and fill it to their nominal capacity with water at specified condition, Close the containers with their usual closure Containers are subjected to the vibration on the vibration tester at a specified frequency and peak acceleration for predetermined time. At the end of the test closures are observed for any leakage The container should not show any leakage. Corporate Training & Planning

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VIBRATION TESTER Corporate Training & Planning

Air pressure leakage test is carried out by maintaining the specified pressure inside container and detecting any leakage with water or soap solution. This test is carried out for particular type of containers such as mineral water bottle. PROCEDURE Take a container to be tested and connect to the container by tightly fitting the rubber plug in the mouth of container Emerge the container in the water reservoir or soap solution for detecting any leakage by bubbles of air escaping through the water. Regulate the air with the help of air pressure valve Observe any leakage by bubbles of air escaping through the water or soap solution Corporate Training & Planning

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HANDLE PULL TEST Handles are generally provided larger size of container (5 Ltrs and above) for easy handling. Handle pull test is carried out to check the ability of the handle to bear the weight of the filled containers. PROCEDURE Take the container and fill it with suitable material equal to the double of nominal capacity or specified load. Hang the above filled container to a vertical pull from a fixed point for the specified period. After the specified period check for any damage to the handle or the hinge. The handle or hinge should not show any damage Corporate Training & Planning

The plastic containers used for packing and storage of various chemicals, detergent and other surface active substances which may cause cracking to the container. Plastics containers may exhibit mechanical failure by cracking under condition of internal or external or combination of stresses in the presence of environments such as soaps, wetting agents, oil, detergent, heat etc. test is carried out by keeping the specimen in contact with chemical active agent under specified condition of temperature & time. Specimen are checked for any cracking or surface irregularities Corporate Training & Planning

PROCEDURE Take about 15 containers and fill with test liquid their nominal capacity Heat seal with the laminate and close with usual closure Put the containers in plastic bag in vertical position and close by means of rubber band . Place the container in the oven at the test temperature Inspect the container for environmental cracking failure after an interval of 24 hrs. Remove the failed container and record it’s failure and time. Continue the test with remaining container until all fail or to a maximum of 360 hrs. Calculate the percentage of failure using following formula Failure % = (n/N) X 100, Where, n = Number of containers failed at a given time N = Number of containers Tested Corporate Training & Planning

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OVERALL MIGRATION DEFINITION Migration is the mass transfer (transport) of material from plastic( packaging ) in contact with food under the specified condition is called Migration. When plastic & foods come in contact the constituents which may be transported are monomer, oligomer, additives such as plasticizers, stabilizers, antioxidant, slip agent, antistatic agent etc. present in the material. Accumulation of toxic materials from plastic may lead to contamination of food hazards and may cause serious ill effects. Corporate Training & Planning

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TYPE OF MIGRATION There are two types of migrations 1) Specific migration 2) Overall/Global migration Specific migration : Where the migration of as single chemical species is measured that is called specific migration. Overall/Global migration : Where the total migration of all species migrating is measured Migration varies with time and is influence by the temperature Corporate Training & Planning

Migration operate in two ways Mass transfer from plastic package into food in physical contact with it, causing contamination, adulteration, diffusion and leaching.   Example: Plasticizers can migrate into the food from plastic film/ container to the point where the containers/film becomes brittle  2. Negative/ reverse migration: is the mass transfer from food into an external acceptor in physical contact with it causing the change in the composition of food leading to adverse effects. Example : By negative migration lipids can migrate from oily food into packaging or conveyor belts to cause structural damage. Corporate Training & Planning

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MIGRATION Two different situations FOOD PLASTICS PLASTICS Corporate Training & Planning

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MIGRATION Over all migration test of plastics is carried out by placing sample in contact with suitable simulants at specified condition and time (as given in IS: 9845:98.) Extraction cell is used for migration test of cut pieces from larger size containers Tested simulants are evaporated and extractive/residue is calculated in mg/dm2 or mg/ltrs or mg/kg or ppm. Extraction Cell Corporate Training & Planning

S. No. Type Description Examples Simulants (1) (2) (3) (4) (5) i I Aqueous non acidic food (pH>5) without fat Honey mineral water, sugar syrups, molasses, skimmed milk, rasgulla, infusions, murabba, yeast paste etc. ‘A’ ii II Aqueous, acidic food (pH 5) without fat Fruit juices, squashes, fruit chunks or puree or paste, vinegar, jams, jellies, carbonated beverages, lemonade,processed vegetables, rennet, preparations of soups, broths, sauces, RTS beverages etc. ‘B’ iii III Alcoholic beverages : Alcohol concentration less than 10 percent ii) Alcohol concentration above 10 percent Beer and some pharmaceuticals syrups Wine, brandy, whiskey, arrack and other alcoholic drinks ‘C1’ ‘C2 ’ Contd...

Sl. No. Type Description Examples Simulants (1) (2) (3) (4) (5) iv IV Oil facts and processed by foods with surface fat or volatile oil Vegetable oils, ghee, vanaspati, cocoa butter, lard, biscuits, spice powder, snacks and savory, chocolate, caramels, malted foods, egg powder, tea, coffee powder, confectionary, fried and roasted nuts etc. ‘D’ v V No acidic foods (pH> 5) or high fat and having high moisture content Butter, bread, pastry, shriek and with low cakes, milk based sweets, ice-cream, moist and fatty confectionary products. ‘ A and B’ vi VI Acidic foods (pH<5) or high fat and having high moisture content Pickles, ketchup, chees, with low curd, fresh and rocessed meat and fish products, sauces having fat, froen foods, mayannaise etc. ‘ B and D’ vii VII Dry processed foods without fat Cereals and pulses, dehydrated vegitable and fruits, dried yeast, com flakes, salt, sugar, milled products, barley powder, oats, vermicelli, spaghetti etc. No end test Corporate Training & Planning

158 3 % Acetic Acid (Time-Temp)
SIMULATING SOLVENTS FOR DIFFERENT TYPES OF FOODS AND TEMPERATURE – TIME CONDITIONS S.No. Conditions of use Type of Food Water (Time-Temp) 3 % Acetic Acid (Time-Temp) 10% Alcohol (Time-Temp) 50% Alcohol (Time-Temp) N-Hepten (Time-Temp) (1) (2) (3) (4) (5) (6) (7) (8) i) High temperature heat sterilized (Retorting) I,II,IV, V & VI 1210C 2 h -- 660C for 2 h ii) Hot filled or pasteurized above 660C, below 1000 C 1000C 490C for 30 minutes iii) Hot filled or pasteurized below 660C I to VI 700C 380C for 30 minutes iv) Room temperature filled and stored (no thermal treatment in container) and also in refrigerated and frozen condition -do- 400C 10 days

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SIMULANTS Migration test is carried out using the following simulants Simulant ‘A’ Distilled water or water of equivalent quality. Simulant ‘B’ percent acetic acid (w/v) in aqueous soluion (using the simulant ‘A’) Simulant ‘C1’ percent ethanol (v/v) in aqueous solution less than 10% (v/v) Simulant ‘C2‘ % ethanol (v/v) in aqueous solution for foodstuffs having alcohol more than 10 percent and less than 5 % (v/v) Simulant ‘D’ n-heptane - shall be freshly distilled before use. Simulant ‘E’ Rectified olive oil or mixture of synthetic triglycerides sunflower oil Corporate Training & Planning

Sl. No. Method Product Description Sample Size 1. Method-I Finished container (within 2 liters) or sealable single multi-layered flexible films (one side exposure) Area of exposure is 1000 cm2(in case of films 2 pouches of size 125 x 200mm) 2. Method-II Large containers > 2 ltrs capacity, Area of exposure – 5 pieces of size 10 cm x 10 cm 3. Method-III Both side exposure for film, which can not be heat sealed 4. Method-IV Closures, sealing gaskets Area of exposure – 10 cm2 or ten lids. 5. Method-V Materials intended to come in repeated contact with food stuff

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PROCEDURE Following procedure is followed: Select appropriate simulant, test method and test conditions as applicable from the above referred list Select the appropriate size of sample from container/ film etc. Fill the container with simulant to it’s capacity and close with it’s closure Place the filled container in air oven at specified temperature and time In case of large size of container cut pieces each of size 10cm x 10 cm are taken so that test exposure area is is 1000 cm2 Take specified quantity of simulant in extraction cell as shown above Dip the test pieces in simulant and cover with lead and place with hot oven at specified temperature and time Corporate Training & Planning

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PROCEDURE Remove the test pieces and transfer content of the extractive cell in clean pyrex beaker and evaporate to 50ml Then transfer in petri dish and evaporate in hot air oven After complete evaporation remove from oven, cool to room temperature. Weigh petri dish with residue to the accuracy of 0.1 mg. Calculate amount of extractive in mg/dm2 or mg/ ltr or ppm using formula Extractive amount(Ex) : M/A x 100 mg/dm2 or : M/V x mg/kg or mg/ltr or ppm. or Where, M = mass of residue in mg minus blank sample residue A = Total surface Area in cm2 exposed in each replicate V = Total volume in ml. of simulant used in each replicate Corporate Training & Planning

SIGNIFICANCE: This test indicates the adhesion characteristics of the container to the ink used for printing of product details and information's on containers such as capacity, content, manufacturing, packaging date and other instructions about product. These information's are vital for the consumers till the product is used and disposed. This test is carried out by applying transparent pressure sensitive tape on to the printed area, then slowly remove and checked for removal of printed matter for container. PROCEDURE Take container and apply 25mm wide transparent pressure sensitive tape on printed area one around circumference another long the height of container Press tape firmly on container and leave for 15 second Remove tape by pulling cm/sec. From one end at 900 container surface There shall no removal of print from the surface of the container Corporate Training & Planning

Significance : When the Product comes in contact of printed matter of container under rubbing action at normal or high temperature there may be removal of printed matter. Thus the information about the product may be lost. This test is carried out by smearing the printed area of the container with product and left for the specified time. Subsequently, the container is washed and rubbed with hard tissue paper and checked for any significant removal of printed matter from the container. PROCEDURE A section of the container from the printed area is cut and smeared on the printed area , with the product at C and then left for 1 hr. The smeared section of the container is washed with cold water Again the section of the container is rubbed firmly with hard tissue paper ten times. Then the surface of the section is checked for any significant removal of the print from the surface There shall be no removal of printed matter from the surface Corporate Training & Planning

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TRANSPARENCY TEST DEFINITION & SIGNIFICANCE Transparency of material is defined as the extent to which light is transmitted through it so as to render an object placed beyond it visible. This test is generally applicable for the containers used for packaging of Natural mineral water and packaged drinking water, baby feed bottle etc. Mineral water are needed to be viewed clearly from outside of the containers for any foreign suspended particles level, of content etc. Minimum light required transparency in the container is 85%  Corporate Training & Planning

166 PROCEDURE The integrated ball type light transmission apparatus is used Test pieces of 50 mm x 50mm are cut from container The white standard plate is installed and reading(T1) of current meter device is adjusted to 100 by incident light. Installed the test specimen in place of white standard plate and measure the current meter reading as (T2). The transmittance is calculated by the following formula T =( T1/ T2) x 100 Where, T = full light transmittance , (%) The Transparency of a container shall be not less than 85% in light transmittance. Corporate Training & Planning

Corporate Training & Planning

SIGNIFICANCE : These test is carried out to check the suitability of the container and material for packaging and storing of drinking water for the human consumption When the water is stored in the container for a longer period it may acquire some unpleasant, bitter taste or smell concentration of some odiferous substances. PROCEDURE : Five containers are filled to its nominal capacity by mineral water and closed tightly with closure Keep at C in air oven for 30 days Two containers are opened and examined at regular interval for any disagreeable odour or smell. At the end specified period, after 30 days the water is checked for any unpleasant odour or taste. Corporate Training & Planning

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WOVEN SACKS TESTING Corporate Training & Planning

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WOVEN SACKS TESTING Advantages of Woven sacks over conventional sacks Light weight High production rate & hence cost effective High strength Vs wt ratio Good permeable resistance Non biodegradable Good chemical inertness Good printability, easy & wide colourability Materials are used : Raffia grade of HDPE/PP is used Corporate Training & Planning

Film is produced by blown film /cast process which is subsequently slit in desired width by slitting process Slit film is heated approximately to softening temp over hot plate or in the air oven and stretch in lengthwise direction to achieve high orientation in the lengthwise direction. From those tapes fabric are weaved. For packaging of fertilizers, powdered chemicals, pesticides or other hygroscopic materials fabric is coated with a thin layer of LDPE/PP material generally of order of 25 micron thickness. From these fabrics bags of various sizes are prepared by stitching with the tape of about 20% higher denier. Thus the quality of the woven sack depends on tape, fabric and stitching Therefore the quality control test is necessary to performed of (a) Tapes, (b) Woven fabrics and (c) Woven bags. Corporate Training & Planning

172 TESTS S.No. On Tape Fabric Sack Bag 1. Identification of material
Width of the tape Thickness of the tape Linear density (a) Linear (b) Text 4. Tenacity 5. Breaking load & tenacity 6. Heat Shrinkage 1. Capacity & dimension 2. Mass 3. Ends & picks per dm 4. Distance between two rows of stitches 5. Seam depth 6. No. & type of stitches 7. Hammed width of sack mouth 8. Thickness of loose liner 9. Liner width & bottom seam 10 UV resistance 11 Mass of bale of sacks

DEFINITION It is the mass certain length of the tape and expressed in either in denier or Tex. Denier : It is the mass in gms of 9000mtrs length tape. Tex : It is the mass in gms of 1000 mtrs length tape  SIGNIFICANCE Determination of linear density is useful for control of mass obtained and it’s uniformity through out the bag. It is used for quality control of the yarn. Apparatus Denier or micro balance capable of measuring the mass to the accuracy. Measuring tape, Wrap reel. Drying oven capable of maintaining temp. of 105 ± 30C. Desiccator with suitable desiccant. Test Specimen Take suitable length of tape in multiple of 1m for tex & 9m for diner measurement by wrap reel Corporate Training & Planning

PROCEDURE For determination of denier Set temperature of oven as 105 ± 30C and allow to maintain Cut the suitable length of tape and condition of air oven maintained 1050C till it achieve the constant mass. Use the denier and micro balance as may be the case Using Denier balance : Take a tape of 90cm length & measures its length accurately. Place on the denier balance. The denier balance will give the denier directly. Using micro Microbalance Take tape of suitable length having a mass at least 100 micro gram. Weigh on microbalance accurately in grams. Multiply the required factor to achieve the mass of the test for 9000 m length. For determination of Tex. Take tape of 10m length duly condition in the air oven at 1050C. Measure the length accurately by measuring tape by applying pre-tension of 0.5N/tex. Take the mass and microbalance Result : The linear density to the specification on requirements Corporate Training & Planning

The following factors affect the variation in the Denier High melt flow index material. Uneven heating on hot plate. Uneven stretch of tape Variation in heating temp. of barrel & dies. Uneven width of spacer Tight winding at winding stations. Linear density varies due to Initial film thickness or Improper orientation of tape Temperature variation during manufacturing and stretching process. Corporate Training & Planning

DEFINITION : It may be defined as the ability of woven sack to retain it’s breaking load after exposure to UV radiation under specified condition and duration in UV radiation. SIGNIFICANCE In certain packaging application packed HDPE/PP woven bag are retained for long duration in out door weather condition. Due to UV radiation the detoriation of physical properties the load carrying capacity of woven bag declines. Thus this test is useful for quantity control, R&D development and characterisation of material APPARATUS UV tester fitted with fluorescent lamp type B Capable of maintaining temp of 50 to 600C in heating & cooling mode. Fitted with temperature, humidity and UV sensing device. Capable of programming and run according test programme. Specimen rack for exposure to UV. Tensile testing machine of suitable capacity. Testing fixture for holding test sample. Steel rule/ measuring tape. Corporate Training & Planning

TEST SPECIMEN Cut pieces of 32 x 5 cm : 10nos and divide in two sets Procedure Set the UV test programme in the UV tester such as to run the machine 8 hrs at 800C with UV radiation. Alternating with 4 hrs at 500 C with condensation. Take one set of test pieces for UV exposure Expose the test specimen to UV light alternatively to the condensation. Continue this test cycle for 144 hrs. After 24 hrs take out the test pieces from the UV chamber. Conduct the tensile test in the tensile testing machine and find out the breaking load of test pieces before and after UV exposure Compare the breaking load before and after UV exposure Result : The percentage retention of breaking load after UV exposure should not be less than 50% of unexposed Corporate Training & Planning

Definition : It is the breaking load of tape divided by the linear density of unstrained material. It is usually expressed in g/ tex Significance : Testing of the tape determines the capabilities of woven sack to take-up the load of the bag when it is handled in the filled condition during real life application.  Apparatus Tensile testing machine capable of measuring breaking load accurately to 10 Newton and stretching of the test sample at the rate of 300±15mm/minute. The machine should be provided with. Suitable clamp for holding sample mechanically or pneumatically without damaging the test price at clamp point. Machine shall be capable to adjust any distance between clamps. Machine shall be capable to provide pre-tension of 0.5±1 N/tex to test specimen when clamped. Capable to record the load and extensions. Denier or Microbalance.  Corporate Training & Planning

PROCEDURE Determined the linear density of the tape using denier balance or microbalance. Calculate the pre-tension load equal 0.5N/ tex Cut ten test specimen of about 500mm long. Set a distance of 250±2 mm between clamps in machine. Clamp the test specimen between grips and light mechanically or pneumatically. Apply pre-tension of 0.5 N/ tex using simple tension device. Set the test speed in the machine. Stretch the tape between two grips at the rate of 300±15 mm/min to its rupture. Record the breaking load is N and elongation in mm. Open both clamps and remove the broken pieces. Repeat the same procedure for other test pieces Corporate Training & Planning

SAFETY Set limit switches of tensile testing machine within operating range. Apply accurate pre-tension on the sample. Determine linear density of tape/fibre. CALCULATION: Calculate the tex and tenacity of tape using following formula Tex = 100 X 10m L Where, M= Mass of specimen in gm.; L = Length of tape Tenacity = Mean breaking load N Mean linear density in tex. Corporate Training & Planning

The following factors are affecting the tenacity of the tape :- Type and intensity of cooling after extrusion Degree of orientation of molecules during drawing Presence of nucleating agent in the material. Stretch ratio: Tenacity increases with increase in stretch ratio. Type of film & tape manufacturing process i.e. cast or blown process. Up to a certain limit tenacity increases with increase in stretch temp. & the starts decreasing. Corporate Training & Planning

Breaking strength of fabric signifies the load carrying capacity of bag in the filled condition. Test is performed on test sample of size 325 x 60 mm cut from the woven sacks . Samples are preconditioned tensile strength test is conducted in tensile tester / UTM taking gauge length 200 mm. The rate of separation is set to the value so that the breaking should occur between 20+3 seconds of test starting. Percentage elongation calculated by measuring the distance between grips at the time of break against the gauge length. The Tenacity is the important term related with the breaking strength. Corporate Training & Planning

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PLASTIC FLOORING Corporate Training & Planning

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PLASTIC FLOORING MATERIALS USED FOR FLOORINGS: Polyvinyl Chloride (mostly used) Polystyrene (wall tile application) Thermo set Epoxy ADVANTAGES OF FLOORING: Fast and clean installation Available in various color, texture, shades and printed form Water repellant Self extinguishing in nature Good abrasion and scratch resistance Dust free Noise absorbing INTRODUCTION When replacement of conventional material by plastic material has started, the trend has also splashed the sector of flooring & wall tiling. Mainly the applications are in train, office decoration; shopping mal etc. apart from these numerous advantageous properties of various polymers has brought their acceptance in coating application over conventional materials, including coating over floor & walls. Corporate Training & Planning

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COLOR & FINISH TESTS ON FLOORING Generally following tests are important for the flooring and tiles. It is described as below: The floorings are available in variety of color and textures and as per the aesthetic requirement of the products. So to conform the aesthetic requirements and to the requirement of the specification this test is important. This is the visual observation as per the agreement by the purchases & the supplier. In case of plain tiles there should be uniform color distribution whereas for mottled tiles the color should be randomly distributed Corporate Training & Planning

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PLASTIC FLOORING DIMENSION & TOLERANCE When the tiles are to be pasted on the floor, the dimensional uniformity is mostly required to avoid the mismatching or gap between them. Generally the tiles are produced in the standard dimension of 200 & 250 mm square and thickness such as 1.5, 2.0, 2.5 & 3.0 mm etc. The length & width of tiles are measured by traveling microscope and measuring tape immediately after conditioning at a temperature of 27±2oC for at least 60 minutes. Thickness is measured by micrometers. SQUARENESS The tiles are generally available in the square shape as per the requirement of the standard. So these are to be perfectly square otherwise one tile would mismatch with others during their installation on the floor. To check the squareness of the PVC floor tiles the one side of the samples is held against the one side of L shaped metal jig( L angle is of 90oC) comprising two arms each of length greater than the side of the tile. Any gap between the sides of the tile and metal arms are measured by the feeler gauge or microscope. Corporate Training & Planning

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PLASTIC FLOORING DIMENSIONAL STABILITY The tiles generally get exposed in different environmental condition in different seasons through out the year in its use. So this is very important that the tiles should retain it’s actual dimension during varying atmospheric condition. The test is carried out as follows: The test specimens of 200 X 200 mm has is taken and marked along each liner dimensions of the surface of the test specimen. These are samples placed horizontally on one shelve of the oven at 80 ± 2 oC for about 6 hours. After this test duration the samples are removed and cooled to room temperature and again conditioned 1 hour. Lastly, the distance between the reference marks is measured. The change in the distance between each pair of reference marks are calculated as the percentage of original distance and reported as dimensional stability. Corporate Training & Planning

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PLASTIC FLOORING DEFLECTION During the installation of the tiles sometimes it is required to bend the tiles. During this action it should not be crack or break. This test is actually confirming this requirement. Test pieces of 200 X 50 mm are cut pieces from PVC tile and conditioned then placed over two supports of circular shape (200 mm apart) and then at the centre point, the sample is deflected downwards at the rate of 100±3 mm/min. by moving the third rod nose till deflection of at least 25 mm is obtained without break. The average amount of deflection without break is reported. Corporate Training & Planning

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PLASTIC FLOORING IMPACT Impact strength of the tile measures the toughness of the materials. This test reflects the resistance of flooring sample to fracture in case anything drops from height on it during its use. This shows toughness of materials. In this test known amount of impact load is dropped from the certain height over the tile placed over annular surface supported on steel ball of about 25 mm diameter for number of times. The test pieces are then examined visually for cracks in enough light without flexing and reported failure if cracks found. COLOUR & FASTNESS TO DAYLIGHT Colour is one of the main aesthetic requirements of the tiles. During their use the tiles may be exposed to sunlight coming through the window. This test is to ascertain the colour of the tiles. It should not fade due to sunlight that extent during use. The test is generally visual observation, which conform the standard requirement. Corporate Training & Planning

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VOLATILE MATTER The tiles are produced from such materials and compounds, which contain a number of ingredients to improve properties and processability. Some of these ingredients are volatile in nature, which may evaporate under heat and other environmental condition. Thus the quantity of ingredient material may change and hence performance of flooring is affected. Therefore the measurement of volatile matter in the flooring & tiles are important. To measure the volatile matter a test piece of about 200 X50 mm is cut from PVC tile and weighed on balance and placed in the over at 100±2°C for 6hours. After 6 hrs sample are removed and coded in air and reweighed. The percentage loss in mass is calculated and reported as volatile matter. CURLING During the use of tiles they may come in contact of different types of forces and substances due to which the tiles may curl and aftermath of that peeling may occur. This test is to measuring the tendency of the tiles to curling & hence future peel out. To perform these test two-test specimens measuring 150X150mm is taken and placed over slab covered with wick material in the water bath. The retention period is 72hours at 27±2°C. At the beginning and end of this period the gap between the test piece surface and a light straight edge placed on each pair of diagonally opposite corners are determined. The average of the amount of curling is reported. Corporate Training & Planning

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INDENTATION Resistance to indentation & extent of it is a very important parameter to be for the materials used as flooring. This test is a measurement of hardness of flooring. The PVC tile sample is taken place on the rigid plate. A load of about 13Kg is applied through hemispherical head attached with dial gauge. The depth of penetration of hemispherical head on the surface of flooring is recorded. RESIDUAL INDENTATION This is the measurement of retention of actual indentation occurs. In this test, at first the thickness of the test piece at the same point by means of the indenting tool for a period of 10 minutes. After completion of 10 minutes the load is completely removed from the test piece and stand at a temperature of 27±2oC for a period 60minutes. Lastly, the indentation is measured for the nearest of 0.01mm and average value is reported. Corporate Training & Planning

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RESISTANCE TO VARIOUS SUBSTANCES During their use in the flooring they may come contact of different types of substances such as tea, hot water, various food gradients, soap solution, phenyl etc. The tiles or sheeting should not be affected by this type of substances whose basic materials are generally weak acids and bases. This test is the indication of the resistance of flooring against these various substances. Separate test pieces of 50 X75mm cut from tiles or sheets and kept in four types of liquids i.e. i) Isopropyl alcohol; ii) Light mineral oil; iii) Cotton seed oil; iv) 2% NaOH Solution at room temperature for about 46 hours. Then scratching on the surface of the tiles is done. The resistance in the form of scratchability is evaluated by measuring the load & width of scratch. FLEXIBILITY The flexibility of the floor tiles is affected by change of its use temperature. For example at reduced temperature the molecular movement of material is reduced hence it becomes less flexible whereas at higher temperature molecular movements are increased so the flexibility of tiles increases. Due to these changes in temperature the deformation behavior of tile under load is changing. This affects the performance of flooring and tiles. Therefore measurement of flammability of floor tiles is important. A 50X225 mm test pieces is taken and conditioned at 0±0.5°C for about 60 minutes in air and then bent by hand over steel mandrel whose temperature is at 0°C through an arc of approx.180°C in 3 seconds. The bent portion of test pieces are then examined in light under 4 X magnification for any cracks, breaks and other signs of failure. Corporate Training & Planning

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PLY ADHESION The tiles them sheeting are fixed on the floor by adhesive and it is to confirm a very good adhesion between otherwise peeling will occur very easily. This test is conducted to ascertain the very good bondability between tiles and the floorings. To perform this test 150X50 mm test pieces are cut from the specimen. Three parallel lines are marked and each of them, then partially immersed in the ethyl acetate to the depth of more than 20 mm for 45 minutes. The immersed portion of laminate is separated by hand and dried about for 90 minutes. Then the load required to separator the sample for about 75 mm is measured by using tensile testing m/c. The ply adhesion is calculated by dividing average load of separation by width of test piece. MOISTURE MOVEMENT The dimensional stability is very important for the tiles. This may be affected by various ways such as temperature, moisture, water etc. The two test pieces each of 225 mm dimension are taken and conditioned for specified period. Then the specimens are marked along each liner dimensions of the surface of the test specimen. Then the distance between pairs of marks are measured and placed on perfect flat surface with the steel plate on top of it. The test piece is then put over the layer of glass balls in tray containing water for 72 hours at 27±2°C. After the time is over the test piece is removed from the water and distance between the pair of marks is measured. The change in the distance between corresponding marks expressed as a percentage of the original distance is the measurement of moisture movement. Corporate Training & Planning

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HEAT AGING & EXUDATION PVC is compounded with various substances to make it flexible and ready for processing. During the use PVC tiles come across different environmental conditions. Therefore there is the possibility of migration of some compounds to the surface. Thus the product remains no more flexible. This test is to observe the retention of quality & flexibility of PVC flexible flooring after aging. Test sample of 50 X 225 mm dimension are taken and placed in a air oven for 15days at 70±1°C . After 15 days the samples are removed, cooled and conditioned for about 60 minutes. To check exudation a clean white papers is rubbed over the wearing surface. The greasy stain on the paper is the mark of exudation occurrence and hence failure. Subsequently other samples are bent around the mandrel through an arc of 180° in approx 3 seconds. The bent portion is observed in good lighting under magnification for any sign of crack, break or other failures. Corporate Training & Planning

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ELASTIC PRODUCT: It is the test for determining the resistance of flooring to be stretched in a direction and permanent deformation prior to failure. To conduct this test 25 mm wide and 75 mm long six test pieces ( three are parallel and three are perpendicular to calendaring axis) are first conditioned and subsequently tensile test is performed at a specified speed. The mean of six determinations of the product of tensile strength and elongation of each sample is the measurement of elastic product of the sample. ABRASION RESISTANCE: The flooring comes across the abrasive action during their use. Due to abrasive action there is the possibility of loss of material from the surface of tiles, which may affect its original aesthetic look and appearance. Thus It is required to measure the resistance to wear of PVC floor tiles against the abrasive force. This is tested by cutting the sample from the tiles or sheeting. The test is performed in the taber abraser under a specified load for 1000 cycles. The loss in weight of material after abrasion is reported. Corporate Training & Planning

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CELLULAR PLASTICS Corporate Training & Planning

DEFINITION: Cellular materials (Expanded or foamed) is defined as the material containing many cells (either open, closed or both) dispersed throughout the mass. REASONS: Reduction of cost. Improved functional performance. Potential for integrated design. Weight reduction in automobiles Reduction of flammability Reduction in production of smoke in building To provide better insulation in building. Corporate Training & Planning

Cellular polymer can be divided into three classes. Rigid Semi-rigid Flexible foam Further foam can be sub-divided as: - Open cell: In open cell foam, gas cells are interconnected with each other. Closed cell: In closed cell foam each gas cell is totally enclosed by thin plastic wall. Corporate Training & Planning

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METHODS OF FOAMING Foams are produced by following three principal methods:- Mechanical Physical Chemical Mechanical: In this system resin as a solution in emulsion form is vigorously agitated unit it becomes foam of air bubbles. Then it becomes solid foam by fusion e.g. PVC plastisols can be mechanically foamed. Physical: The compressed gases or chemicals which change their physical form during the foaming process e.g. PE foam. Chemical: The liquid resin reacts with the chemical compounds under heat by mixing or dissolving. The gas causes the foaming action with in the molten or liquid resin e.g. PU foam. Corporate Training & Planning

Table CHARACTERISTICS OF PLASTICS FOAM Polymers Density Lbs/cu.ft. Type Cell structure Available Form Characteristics uses A B S 31-62 Thermoplastics rigid Closed Pellets Picture frames, ice buckets, wall plaques. Cellulose-accetate 6-8 Boards and rods Life buoys, aircraft floats, fuel tanks. Epoxy 2-23 Liquid and precast sheets and blocks Accoustical insulation, refrigerator doors, pontoons gun stocks, furniture. Ionomer 2-20 Thermoplastics Flexible Sheets and rods Marine floats, gaskets insulation, packaging. Phenolic 0.1-22 Closed & Open Liquid foam in place resin Cores for boat hulls, pipe, Insulation, cores for plywood insulation. Polystyrene 1-10 Expanded beads boards and blocks Hot and cold drinks cups packaging food containers, insulation. Polyurethane 1.5-70 Thermoplastics flexible or rigid Open & Closed Foam-in-place liquids boards and blocks Freezer insulation Marine floatation, furniture cushioning, packaging. Polyethylene 2-35 Sheets, rods, tubing moulded parts Packaging cushioning, life jackets, boat bumpers, gaskets Polyvinyl chloride 3-45 Sheets, moulded shapers and expandable beads Thermal insulation, atheletic gear, ice buckets, flooring carpet backing Silicon 9.6-31 Liquid of sheet Plastic surgery, heat sealing blankets sponges. Corporate Training & Planning

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PROPERTIES OF FOAM The properties of the foam depend upon the following factors: Base polymer. Cell structure and size Density Porosity Physical properties Applications. Corporate Training & Planning

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DENSITY INTRODUCTION: The physical properties of the cellular plastics is related to it’s density. Many physical properties particularly strength of cellular plastics vary directly with density DEFINITION: Density is defined as the weight per unit volume of cellular material. It is expressed in Kg/m3 CALCULATION: Density (Kg/m3 ) = Weight of Specimen (Kg.) Volume of Specimen (m3) FACTORS AFFECTING: - Density of foam depends upon the base material of foam. - Type and characteristics of cell, it’s size and structure etc. - Conditioning of foam and skin of the foam Corporate Training & Planning

- Tensile Strength - Compressive strength - Shear strength and modulus - Flexural strength - Impact strength - Tear Strength - Fatigue strength -         Resilience -         Abrasion Resistance -         Indentation Hardness -         Friability -         Compression Set -         Creep Corporate Training & Planning

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TENSILE STRENGTH INTRODUCTION: Generally flexible cellular plastics are characterized by tensile strength. DEFINITION: It is defined as the maximum tensile stress sustained by material at rupture or break. It is expressed in kg/cm2 . Tensile strength is calculated from the maximum load of rupture during tensile divided by original cross sectional area of specimen. Test Specimen: Dumbell shaped specimen as shown in side. Corporate Training & Planning

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TENSILE STRENGTH TEST METHOD : ISO: 1798 & ASTM D3574. PROCEDURE: The specimen is preconditioned at specified temp. and humidity. Width and thickness of test specimen is measured and cross sectional area is calculated. Test parameters such as test speeds, grip length etc. as specified by the standard is selected and set in the testing machine Specimen is pulled between the jaws at the rate such that test specimen breaks between 3 to 6 minutes. The load and extension at break point is recorded. CALCULATION: Tensile strength is calculated by using following formula: Tensile Strength (Kg/cm2 ) = Load at break (kg.) Cross sectional area ( cm2 ) % Elongation at Break = Change in length x 100 Original length Corporate Training & Planning

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COMPRESSIVE STRENGTH INTRODUCTION: Many materials such as low-density rigid cellular plastic material are crushed at lower stress, when subjected to compressive load. The compressive properties of material include compressive Strength, compressive strain, compressive modulus etc. DEFINITION: It is defined as the maximum compressive stress which the material is capable of sustaining for very short time at a fixed point in the loading cycle. compressive modulus is the ratio of stress to corresponding strain below the proportional limit of material when under compression. It is expressed in force per unit cross-section area of specimen. SIGNIFICANCE: This test provides the information about behavior of material under compression load. Used for R&D and verifying the process. Used for quality control and inspection of material. Corporate Training & Planning

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COMPRESSIVE STRENGTH TEST SPECIMEN: Test Specimen of square or circular cross section of minimum 25.8 cm2 and maximum of 232 cm2 cross-section area and a height of 25.4mm is cut from the foam. PROCEDURE: Specimen is pre-conditioned and it’s dimension is measured. When It is subjected to compressive load between compressive plates at the rate of 2.5mm/min in the testing machines. Compression is continued till yield point is reached or up to 13% decrease in the original height of specimen. Compressive load and deflection is recorded at regular interval at each point. The compressive strength and modulus is calculated. FACTORS AFFECTING: Base material of foam and it’s density. Higher is the density higher will be the Compressive strength. It depends upon the direction of orientation of cellular structure. Compressive strength will be higher in the direction of orientation compared to non-oriented direction. The structural parameters such as cell size, cell size distribution, Anisotropy etc. Corporate Training & Planning

INTRODUCTION: Shear strength of cellular materials has particular importance in the construction because in most construction applications cellular materials are loaded in compression, tension and shear. DEFINITION: Shear strength is defined as the maximum shear stress of material at rupture. It is calculated from maximum load during the shear test divided by cross-sectional area of specimen. TEST METHOD: Shear strength of cellular material is determined as per ISO: and BS: 4370 part-II method 6. TEST SPECIMEN : Test specimen of 250 x 50 x 25mm parallel piped specimen is taken PROCEDURE : Shear force is applied via two mild steel support bonded to the largest surface. Shear stress is applied in a direction parallel to longitudinal axis of specimen by placing the specimen and supporting vertically between the movable 1mm/min. The force and deflection are recorded. Corporate Training & Planning

CALCULATION: Shear strength is calculated by using Shear strength = 100Fm/ l b Where, l = Initial length of specimen. b= Initial width of specimen. Fm= maximum force applied to the specimen. Shear modulus (G) = 1000dΦ / lb. Where, Φ = Slope of linear portion of force deflection diagram in N/mm. d = Thickness of specimen. Corporate Training & Planning

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FLEXURAL STRENGTH INTRODUCTION: Flexural strength is measured in similar manner as used for non-cellular plastics. It is measured by two methods i.e. three point bending system and four point bending system. DEFINITION: Flexural strength is the ability of material to withstand bending forces applied perpendicular to longitudinal axis. It is expressed in Kg./cm2 . TEST METHOD: ASTM D 790, BS 4370 part-1 (method-4). TEST SPECIMEN: Specimen of size 200mm long, 35-70mm wide and 50mm thick are cut from the cellular material and conditioned. Corporate Training & Planning

Dimension of specimen is measured accurately and placed on two parallel support bar 150mm apart Load is applied centrally at the rate of 100mm/min by means of moving bar in the universal tensile machine. Load point at which fracture occurs is recorded and mean result of five measurements is taken. CALCULATION: Flexural strength is calculated as below. Flexural strength = 3 FL / 2bd2 Where, F = maximum force recorded during test ; L = Distance between two support b = width of specimen d = Thickness of specimen Corporate Training & Planning

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IMPACT STRENGTH INTRODUCTION Cellular materials are often used for thermal insulation on pipes with impact protective covering. Foams are also used to protect electronic product from impact load during transit. The closed cell foam provides pneumatic cushioning and hence absorbing mechanism where as open cell foam do not have this energy absorbing mechanism. DEFINITION Impact strength of cellular material is the ability of material to withstand impact load. The material which crush easily on impact may be unable to sustain normal wear and tear that would be expected in service. Impact strength of foam is determined by following two methods (i)  Izod - impact test - known as method A. ii)  Charpy - impact test - known as method B. Izod and charpy impact of rigid cellular plastic is determined in similar manner as for non-cellular material. Detail test procedure is given in chapter Mechanical Properties. Corporate Training & Planning

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TEAR STRENGTH DEFINITION : Tear strength is defined as energy required to propagate a tear through a specified length of that has already been initiated in sample by small nick with a razor blade. SIGNIFICANCE The tear initiation and tear propagation of the foam are important in the packaging. Generally the tear of brittle foam is measured as the maximum tear initiation force whereas for tear propagation is important in tough foam EQUIPMENT: Tear tester or universal testing machine capable of measuring tear force, Razor for notching sample. SPECIMEN: Test specimen of size of 125 – 150mm x 25mm x 25mm are cut Notching is done with razor centrally from one end of cross section to a depth of 50mm. Figure shown. Corporate Training & Planning

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TEAR STRENGTH PROCEDURE: Two nicked edges of specimen are fixed between fixed and moving jaws. Specimen is pulled at the rate of 50mm/minutes. When the tear has traveled 25mm along the test piece then test is terminated and maximum force (F) is recorded CALCULATION Tear resistance(R) is calculated by R = F / d Where, F = Maximum force in Newton. d = Thickness of specimen in meters. FACTORS AFFECTING: -     It is affected by density of the cellular material and it’s base material. -        Speed of testing and depth of notch in specimen. -        Cellular structure, size & it’s orientation. TEAR SPECIMEN Corporate Training & Planning

INTRODUCTION: The properties of cellular material deteriorates when subjected to a large number of repeated cyclic load and deformation. The failure or decay of mechanical properties after repeated application of stress and strain is known as fatigue. DEFINITION: Fatigue life is defined as the number of cycles of deformation required to bring about failure of test specimen under given set of oscillating conditions. SIGNIFICANCE: -   This test gives information about the ability of cellular plastic material to resist the development of crack as a result of large number loading and deformation cycles, which leads to decay and failure. -         This test is also used for research and development. PRINCIPLE: This method is based on measuring changes in thickness and hardness of cellular material due to repeated load by a specified indenter. Corporate Training & Planning

APPARATUS: Equipment consists of a constant load of 750N, an indenter of 250mm diameter capable of oscillating and applying load on sample. A platen for placing test specimen. Dial thickness gauge, a hardness tester for hardness measurement. TEST-SPECIMEN: Test specimen of 380 x 380 x 50mm. At least three specimens are tested. TEST METHOD: The durability of flexible foam is determined by using a shear or pounding force on the foam according to BS, ISO 3385. PROCEDURE: Measured thickness and hardness of the test pieces and then placed centrally beneath the indenter as shown figure. Adjust striking stroke to ensure to correct position for applying load. Lift indenter to its mounting position and drop on test specimen. Apply this test load for 80,000 cycles, then removed and allows to rest for 10 minutes. Re-measure thickness and hardness of tested portion. This shows failure or decay in Mechanical Properties. Corporate Training & Planning

FACTORS AFFECTING: The following factors affect the fatigue & durability of foam: -    Density of cellular material. -    Cell size and structure. - Indenter size, Test load and number of test cycle applied to test. -    Position of fall of indenter. TEST SET-UP Corporate Training & Planning

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RESILIENCE INTRODUCTION: This property of cellular material is important for packaging. This test is useful for determination of both flexible and rigid cellular plastics. DEFINITION: Resilience may be defined as the ability of material to restore the energy without showing permanent deformation TEST METHOD: Resilience can be determined by ASTM D1564. Corporate Training & Planning

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RESILIENCE EQUIPMENT : It consists of a steel ball of inch diameter and arrangement for holding and free fall on the specimen. It shall be equipped with measuring rebound height accurately. PROCEDURE: Place the specimen on the test station beneath the test ball. Set the test height 18 inches and hold the steel test ball. Drop the test ball on the test sample from the set height of 18 inches. Observed and determine rebound height of ball. Express resilience of material as a percentage of drop height that the ball has rebound. FACTORS AFFECTING: Factor affecting resilience is base material of cellular polymer, Density and cell size of cellular material. Resilience is also affected by size of rebound ball Corporate Training & Planning

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ABRASION RESISTANCE DEFINITION: It is defined as the ability of material to withstand mechanical action (such as rubbing, screeching) that tends to progressively remove material from its surface. Abrasion resistance of cellular material is measured in similar manner as is measured for non-cellular material. This evaluation is based on percentage of light scattering by abraded surface compared to the unabraded surface. This also measures of material versus number of cycle abraded. This test is used for testing of both flexible and rigid cellular material. EQUIPMENT AND PROCEDURE: The detailed test equipment, specimen, test procedure and calculation etc. is described in chapter Mechanical properties FACTORS AFFECTING: It is affected by surface hardness of material. - Type & hardness of abrasive wheel; number of test cycles, test load applied in abrasion. - Quality of abrasive wheel and heat dissipation characteristic of polymer. Corporate Training & Planning

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INDENTATION HARDNESS INTRODUCTION: Flexible cellular materials are widely used in the applications of packaging. These materials are designed basically for providing cushioning. Hence protection from the damage of delicate and fragile material from the vibration and other mechanical forces. Low-density cellular material deform quite easily and have discrete cell structure, so re-producible results are difficult to obtained. However with high Density cellular material with fine cell structure or surface skin, durometer hardness is used successfully. PROCEDURE: Durometer hardness test is used for determination of hardness of electrometric plastics. The details of equipment, test procedure etc. is described in the chapter Mechanical Properties. DEFINITION Indentation hardness may be defined as the resistance to indentation or penetration. Corporate Training & Planning

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FRIABILITY INTRODUCTION: Many rigid materials are quite abrasive in nature to oak block of ¾” which is used as standard wearing surface. This block is worn down quite rapidly by cellular material. DEFINITION : Friability may be defined as the ability of foam to easily crumbled, pulverised or reduced to powder. Friability is expressed in percentage of loss of material in pulverization or disintegration process. The loss in weight determines the relative friability of cellular material. SIGNIFICANCE: Determination of friability is not very easy to determine. Therefore it is rarely used for quality control purpose. Friability is used for development of the formulation of rigid cellular materials such as phenol Formaldehyde for specific application. TEST METHOD: Grinding process for testing may be done by using BS 4370 part3 method. Corporate Training & Planning

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FRIABILITY APPARATUS : -  A Ball mill of 260mm diameter and 90mm long containing 3.8kg of 19mm diameter porcelain ball. It shall be capable to rotate at the rate of 60 revolutions per minutes (RPM). -     Analytical weighing balance to the accuracy of 0.01 mg. TEST SPECIMEN: Sufficient numbers of cubes of cellular material each of size about 20mm. PROCEDURE: - Take Sufficient numbers of cubes of cellular materials and take their cumulative weight on analytical weighing balance to the accuracy of 0.01mg. -   Place the cubes in container of ball mill with porcelain ball - Rotate the rpm for 60 revolution. Then test sample are removed and cleaned by vacuum. CALCULATION: Relative Friability (%) = Loss in weight x Original Weight. FACTORS AFFECTING: -          Rigidity of cellular material and it’s base material. -          Diameter and number of balls in the ball mill. Speed and number of revolution of milling : Higher rpm and number of revolution higher will be friability (loss of material) Corporate Training & Planning

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COMPRESSION SET INTRODUCTION: This test consist of deflecting cellular specimen under specified temperature and time. The effect on thickness of specimen is observed. A number of methods are used for determination of compression set of flexible and rigid cellular plastics. DEFINITION: Compression may be defined as the percentage of deflection of cellular material after recovery under specified condition. It is expressed in percentage. EQUIPMENT: Equipment consist of two rigid, flat parallel plate with specimen locking arrangement, spacer and clamps to give required degree of compression and to held plates parallel to each other during test, Dial micrometer etc. TEST SPECIMEN: Five number of test specimen each having thickness equal to 25mm and in size equal to flat parallel plate. Thin specimen are piled to achieve required thickness. Corporate Training & Planning

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COMPRESSION SET PROCEDURE: Thickness of test specimen is measured by dial micrometer. Place the specimen in between two parallel plates of compression set. Deflected specimen either 50% / 75% or 90% with the help of clamp and spacer block as shown in figure. COMPRESSION SET Place deflected specimen in air oven maintained at 700C and 50% relative humidity. Take out specimen from oven after 22 hours and remove clamp within one minute and is allowed to recover deflection for minutes by laying on wooden surface. Re-measure the thickness of the specimen. Calculate compression by using the following formula. Corporate Training & Planning

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COMPRESSION SET CALCULATION: Compression set is determined by using following formula: Cs = T0 - Tr x 100 T0 Where , T0 = original thickness of material. Tr = Thickness after recovery FACTORS AFFECTING: Following factors may affect compression set. Percentage of deflection from it’s original thickness. Test temperature and duration of exposure in the air oven. High temperature of oven and long duration may show higher deformation. Recovery time allowed for this test sample. Higher recovery time may lower the compression set. Density of the foam and cellular structure of foam affect the compression set. Corporate Training & Planning

INTRODUCTION: A number of standard test methods are used for estimating the permanence properties of cellular materials. Most of these are derived from methods, which are used for material in their solid form. Many of these methods have been adopted with no changes. The detail of the test equipment, conditioning and test procedures and other details are described in the chapter Permanence properties. Aging test Dry heat test Out door weathering Steam Auto Clave test Water Vapor transmission rate Chemical Resistance Fungi resistance Simulated Service test Water absorption Corporate Training & Planning

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AGING TESTS “Aging tests” is developed primarily for vulcanized sponge and other electrometric products. This involve determination of tensile strength before and after heat aging. These tests are seldom used for other cellular materials. The details test procedure is described in chapter Permanence Properties CHEMICAL RESISTANCE INTRODUCTION: Chemical resistance of cellular materials is determined by ASTM D471-68,D & D T. These test methods can be used for cellular materials other than those for which they were specifically designed and are generally applicable to all cellular materials. PROCEDURE: In this test pre-weighed sample is immersed in chemical for the specified duration and the resistance to the chemical is determined by the weight loss, swelling and change in physical properties after immersion. The procedure for determination of chemical resistance are described in chapter Chemical properties. Corporate Training & Planning

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DRY HEAT TEST The dry-heat-test consists of exposure of the cellular material to a high temperature in air oven, after which the change in physical properties are determined. Two test methods are used, AST D and D , both of which are designed primarily for flexible urethane foams. These tests methods have found little application with other cellular materials. The detail of the test are described in the chapter permanence properties FUNGI RESISTANCE Fungi resistance of cellular material can be determined by AST D This test is designed for solid plastics but can be used for all cellular materials. Fungus resistance is determined and reported only for the specific formulation being tested. Detail test procedure is described in chapter permanence properties. Corporate Training & Planning

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OUT DOOR WEATHERING Like non-cellular polymeric materials when cellular materials are exposed to out door weather conditions, the characteristics and properties of materials changes under the influence of different weather conditions as a result there is a gradual detoriation in the properties Out door weathering is usually determined by AST D This test method is for determination of out door weathering of plastic materials and also used for all cellular organic, inorganic, rigid or flexible materials. Details of test procedure are described in chapter Weathering Properties. SIMULATED SERVICE TEST: Simulated service tests are another form of aging test and are run on a wide variety of cellular materials. There are various test methods designed and developed for specific materials they can and have found use for simulated service testing of other cellular materials because all methods allow the use of a variety of test-condition options. The option includes range of temperature and humidity. STEAM AUTO CLAVE TEST: There are two steam autoclave tests. AST D and D 2006 have been designed specifically for flexible urethane foams. These test methods have had only limited use in testing other cellular materials Corporate Training & Planning

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WATER ABSORPTION INTRODUCTION: Cellular plastics are extensively used in flotation application because of their ability to maintain a low buoyancy factor. The buoyancy factor is affected by absorption of water by particular foam. The water absorption is expressed in the percentage of change of mass due to immersion. Water absorption is determined by measurement of buoyancy force of the specimen when immerses in distilled and de-aerated water for four days. Water absorption of EPS and rigid cellular material is measured as per the BS 3837 part2 and ISO The test procedure is described below. TEST SPECIMEN: Specimen of 150 x 150 x 75mm shall be cut from foam DEFINITION: It may be defined as the amount of water absorbed by cellular plastic when immersed in water with respect to original mass of materials. It is measured by the change in mass or dimension/volume of the sample w.r.t original. It is expressed in percentage. Corporate Training & Planning

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WATER ABSORPTION PROCEDURE Take weight of specimen on the analytical weighing balance and measure the buoyant force by immersing in distilled water. Place specimen in the stainless steel mesh cage and suspend from the balance and measure the buoyant force. Immerse the cage in distilled & de- aerated water such that water surfaces is 50mm above the top surface of specimen. Cover the container with the non- permeable film to prevent evaporation of water. Take apparent mass after 04 days and calculate water absorption in percentage. EQUIPMENTS-USED: Analytical weighing balance, stainless steel mesh cage (figure shown). Appropriate weight to measure buoyant force, Distilled water etc. Corporate Training & Planning

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WATER ABSORPTION CALCULATION: Water absorption (%) = Change in weight x 100 Original weight. FACTORS AFFECTING: Water absorption depends upon many factors such as base material of foam, cellular structure i.e. opened or closed cell. It depends upon depth of immersion in water sample, surface to volume ratio of specimen etc. Corporate Training & Planning

INTRODUCTION : Resistance to water permeability is an important requirements in various application of cellular plastics particularly in packing, building construction. Water vapour transmission test is used to determine amount of water vapour transfer through the permeable material DEFINITION: Water vapour transmission rate is defined as the water vapour flow in a unit time through unit area of body, normal to specified condition of temperature and humidity at each surface. It is expressed in g/m2 24 hrs. Water vapour permeability is the rate of water vapour transmission through unit area of a flat material of unit thickness induced by unit vapour pressure difference between two specific surface under specified condition of temperature and humidity. It is expressed in g cm/m2 ­day mm Hg) Water vapour permeability is also defined as the product of permanence and thickness of specimen. The unit of permeability is perm- in. Corporate Training & Planning

EQUIPMENT: Micrometer, Analytical weighing balance, Environmental chamber, Glass beaker, CaCl2 etc. SPECIMEN: Specimen from foam is cut in size equal to the internal diameter of beaker having minimum exposure area of 32 cm2 and 25mm thickness Corporate Training & Planning

PROCEDURE (DESICCANT METHOD) : Take desiccant or water in beaker and seal test specimen over the open mouth of beaker. Take weight of sealed specimen with dish on weighing balance. Place sealed specimen assembly at controlled test atmosphere of 380 C and 0-85% relative humidity. Take weight of specimen assembly periodically. In water method, distilled water is used in place of desiccant. Rate of water movement through specimen is determined periodically by weighing dish containing distilled water and specimen. The detailed procedure of water vapour transmission is given in chapter permeability. FACTORS AFFECTING: Density of cellular plastic: As the density of cellular plastic is decreased water vapour permeability is increases. Pressure difference and test temperature: Higher the pressure difference higher is the transmission rate. At increased temperature and humidity water permeability increases. Thickness of test specimen: Thicker specimen shows lower rate of transmission Corporate Training & Planning

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FLAMMABILITY INTRODUCTION: Cellular plastics find numerous applications in construction and packaging industries because of their superior thermal insulation characteristics. Therefore the increased use as thermal insulation of cellular plastics accounts considerable concerned in regard to flammability. By material, Rate of burning/ extent and time of burning of cellular plastics etc. DEFINITION: It may be defined as the ability of material to support combustion, fire endurance, ignition characteristics, rate of burning, extent of burning and time of burning, determination of density of smoke produced by burning in particular condition, Rate of spread of flame on the surface of material, limiting oxygen index etc. Corporate Training & Planning

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FLAMMABILITY TEST METHOD: There are various methods divided for determination of flammability of cellular plastics such as ASTMD 3014 and ASTMD 1692, ASTMD 2863 etc. PROCEDURE: The detail of various test methods / procedure, equipment, specimen, calculation and interception of result etc. of test is given in chapter Thermal Properties FACTORS AFFECTING: Base material of foam and it’s density, influences the flammability of material. Specimen width and thickness affect the flammability. As the volume of material increase (due to increases specimen dimension either width or thickness) flammability is affected. Flame retardant present in cellular material improves the flammability of material. Flammability is also influenced by fire conditions used for test. Corporate Training & Planning

Thermal Conductivity Thermal Expansion Linear Thermal Expansion Cubical Thermal Expansion Heat Deflection Temperature THERMAL CONDUCTIVITY INTRODUCTION: One of the major reasons of the success of cellular plastic in thermal insulation is because of it’s low thermal conductivity, Cellular plastics have lowest thermal conductivity, compared to any material available today. The outstanding thermal conductivity of these materials is largely due to entrapped gases and not only to the polymeric material, which serves mainly as an enclosure for entrapment of gases. Superior insulation ability depends upon many variable factors. Corporate Training & Planning

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THERMAL CONDUCTIVITY PROCEDURE: Thermal conductivity of cellular materials is measured by “Guarded hot plate Method”. The details of the equipment test specimen, conditioning and procedure of determination of thermal conductivity is given in chapter Thermal properties. In guarded hot plate method it consist of guard heater to prevent heat flow in all direction. Test specimen is placed between main heaters and cooling plate (i.e sink). Time required to stabilize input and output temperature is determined. Thermal conductivity is calculated as below. DEFINITION: Thermal conductivity is defined as the rate at which heat is transferred by conduction through a unit cross sectional area. It is expressed by K - factor and expressed as the quantity of heat that passes through a unit cube of the substance in a given unit of time when the difference in temperature of two faces is 10 C. SIGNIFICANCE Thermal conductivity of foam can be used for quality control and inspection purpose and also for research and development of material. It is also used for ranking of different cellular material for conductivity with respect to their density. Corporate Training & Planning

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THERMAL CONDUCTIVITY CALCULATION: Thermal conductivity is calculated as K = Qt / A( T1 – T2) Where, K = Thermal conductivity ( BTU/in/h/ft2 / 0 F) Q= Thermal of heat flow ( BTU/hr) t= Thickness of specimen (in) A= Area of specimen under test. T1= Temperature of hot surface 0 F T2= Temperature of cold surface 0 F FACTORS AFFECTING: Base material of cellular plastics. Density of cellular material with decrease of density thermal conductivity decrease up to certain values but rises again due to increased convection effect. It is also affected by blowing agent used in material. Also affected by cell size, close cell content, temperature and moisture etc. Corporate Training & Planning

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THERMAL EXPANSION Co-efficient of thermal expansion for the different plastics and cellular material is very important and interesting for the designer. Like non-cellular plastic and other cellular plastic material it also expand and contract largely due to change of temperature. DEFINITION: Co-efficient of thermal expansion is determined as the fractional change in length or volume of material for a unit change in temperature. It is expressed in percentage. SIGNIFICANCE: Co-efficient of thermal expansion is used for ranking of different cellular materials based on expansion. It is also used for quality control, inspection, Research and development of material. TEST METHOD: Co-efficient of thermal expansion of cellular plastic is determined by two methods i.e ASTMD 696 and ASTMD 864. ASTMD 696 determines co-efficient of linear thermal expansion and ASTMD 864 co-efficient cubical thermal expansion. Corporate Training & Planning

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THERMAL EXPANSION PROCEDURE: The details of equipment, specimen, conditioning details and procedure are given in chapter Thermal Properties. Test method uses dilatometer for determination of co-efficient of linear thermal expansion and device for measuring change in length (LVDT). A 2 to 5 inches long test specimen is mounted in dilatometer. Test specimen is heated in oven or liquid bath to the required temperature. The change in length is recorded. Co-efficient of linear thermal expansion is calculated as below. FACTORS AFFECTING: Base material and density of cellular material. It is also affected cell size, close cell content, temperature Corporate Training & Planning

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THERMAL EXPANSION CALCULATION: For linear thermal expansion: X = ΔL / Lo Δt = Change in length due to heating or cooling original length x Change in Temperature. Where, X= Co-efficient of linear thermal expansion. Δl = Change in length of specimen due to heating. Lo = Original length of specimen at room temperature. Δt = Temperature difference Cubical thermal expansion is calculated by following formula Z = ΔV / V 0 Δt Where, Z = Co-efficient of cubical expansion ΔV = Change in volume. V0 = Original volume. Corporate Training & Planning

INTRODUCTION: The increased application of cellular plastic as thermal insulator encourages to evaluate this short term effect of heat Determination of Heat deflection temperature test is applicable on rigid cellular plastics. Determination of HDT of cellular material is similar used for most cellular materials. DEFINITION It is defined as the temperature at which a standard test bar of 127 x 12.7 x 6.4 mm deflects 0.01 in (25 mm) under stated fibre stress of either 66 PSI (4.6 kg. / cm2) or 264 PSI (18.5 kg./cm2) TEST METHOD: Heat deflection temperature of rigid cellular plastic is determined according to ASTMD 648. Corporate Training & Planning

PROCEDURE: The detail of test specimen Equipment and test procedures are described and given in chapter Thermal Properties. This method measures a definite temperature at which cellular plastic sample begins to distort under load when heated at a rate of 20 C/min and specified stress. The temperature at particular distortion is taken as heat distortion temperature. FACTORS AFFECTING: Heat distortion temperature will be affected by density and the base material of cellular materials. Corporate Training & Planning

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REASONS FOR PRODUCT FAILURE: There are five major causes for product failure. There are: - Misapplication of materials. Poor Design. Inadequate Control of Materials Poorly Controlled Manufacturing Techniques TESTING OF FRP : It may be divided into following three groups Testing of Resin. Testing of Fibers Testing of Reinforced Plastics (FRP Products). Corporate Training & Planning

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TESTING OF RESIN RESIN: Different resins are used to manufacture FRP products. The resin acts as binding material to the fiber. Following resins are used commonly used for manufacturing FRP products. Unsaturated Polyester resin Epoxy resin Phenolic resin Silicon resin Vinyl ester UNSATURATED POLYESTER RESIN: Unsaturated Polyester resin is mostly used for reinforced plastics. Corporate Training & Planning

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TESTING OF RESIN Epoxy Resin: An epoxy resin is a polymer containing two or more epoxy groups –C–C- . Commercially Epoxy resins is classified as below: Conventional Epoxy resin: based on epichlorohydrin and bisphenol – A. Cycloaliphatic epoxy resin: prepared by utilizing per acetic acid for the epoxidation of an olefin. Epoxy novalac resins: prepared by reacting epichlorohydrin with novalac resins. Others. Hardeners for curing of the epoxy Anhydrides hardeners e.g. Phthalic anhydride, Maleic anhydride. Polyamine hardeners e.g. Diethylene triamine, Teriethylene tetramine. Reactive diluents are added to an uncured epoxy resin to lower the viscosity and provide the better workability of resins. Corporate Training & Planning

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TESTING OF RESIN PHENOLIC RESINS: Phenolic resins are the third most important resin used in the composite. Phenolic resins are derived from the condensation of phenol ( C6 H5 OH) and formaldehyde, HCHO. Phenolic resins produced by much combination of phenol and formaldehyde. Acetic and basic catalysts are employed for curing phenolic resin. Phenolics are used in application were high strength and heat resistance up to 3200 C are required. Generally high pressure is necessary to cure phenolic molding and laminates. Phenolics resins are difficult to handle as compared to polyester and epoxy resin because it liberates water during the polymerization. SILICON RESINS: Silicon resin is the group of polymer that have skeleton structure of alternate silicon and oxygen atoms with various organic group attached.. Resins are used for structural application for the operating temperature range between 260 to 5500 C. Silicon; glass fiber laminates have outstanding electrical properties coupled with mechanical properties at elevate temperature for various specific applications such as supersonic vehicles etc. Corporate Training & Planning

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TESTING OF RESIN In order to ensure the quality of thermo-set resin following tests are carried out. Visual Inspection Viscosity Exothermic temperature Storage life, working life and Gel time Epoxy value (In Epoxy resin) Chemical Composition Specific Gravity Hardness ( of cured resin ) TEST ON FIBERS Tensile Strength Fiber modulus, Shear modulus Density of fibers (ASTM D 1505, 792) Linear Density Fiber diameter Visual Inspection GSM Corporate Training & Planning

MECHANICAL PROPERTIES Impact Strength (Izod & charpy) Drop Impact test, Hardness test (Rockwell & Barcol hardness) Abrasion resistance Scratch resistance Tensile strength Elongation, Modulus of Elasticity Compressive strength Flexural strength Shear strength THERMAL PROPERTIES Heat distortion temperature Marten heat Stability Flammability ( Critical oxygen index ) Rate of burning Co-efficient of thermal expansion Thermal Shrinkage Thermal conductivity Corporate Training & Planning

Arc resistance Insulation resistance Dielectric strength and breakdown voltage Volume and surface resistivity Dielectric constant Loss tangent OPTICAL PROPERTIES Index of refraction Light transmittance Haze / Gloss CHEMICAL & PERMANENCE PROPERTIES Resistance to chemicals Weather resistance Loss on ignition of cured reinforced resin Corporate Training & Planning

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NON-DESTRUCTIVE TEST Visual Inspection : Visual Non-destructive test (NDT) such as discoloration, foreign matter, crazing cracks, Scratches, Dents, Blisters, orange peeling, pitting, air bubbles, porosity, resin rich and region starved area, wrinkles and to extend Ultrasonic Sonics X-ray & Radiography Electrical properties for NDT Microwave techniques Infrared / thermal NDT Resin Testing Visual Appearance Corporate Training & Planning

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VISUAL APPEARANCE Visual appearance of the resin is an indicator of change of resin characteristics such as advancing of polymerization and curing. Due to chemical reaction during manufacturing or storing or both, the changes in color of the resin can take place SIGNIFICANCE: This can be the indicator of change in quality and condition of resin. This test is used for inspection and quality control of resin. Impurity present in resin may change the viscosity and work life of resin PROCEDURE: Take a transparent and clean glass beaker so that there is no foreign material present. Pour sufficient quantity of the resin sample in glass beaker. Place the beaker with resin sample under the light and observed through the wall of beaker. Any unusual color or foreign matter observed are recorded. Corporate Training & Planning

INTRODUCTION: The determination of the specific gravity and density of the resin is very important. The specific gravity and density of the resin can be measure both in liquid and solid form. The density of liquid resin is determined by ASTM D For solid, it is determined according to ASTM D 792 and ASTM D Using displacement and density column method. DEFINITION: Density of cured plastic resin is defined as the weight per unit volume and it is expressed in g/cm3 SIGNIFICANCE: This test is also used to characterize the resin. The physical, mechanical and other properties of resin depend upon the density of resin. Used for quality and process control. Corporate Training & Planning

TEST PROCEDURE: The test equipments, procedure, specimen, observation, calculation and other details for determination density and specific gravity of the cured resin according to ASTM D 792 & ASTM D 1505 is described in the chapter Mechanical Properties. FACTORS AFFECTING: It depends upon the material of the resin. Density of cured resin is affected by the rate and extent of the curing and hardener used. High degree of curing yield higher density. Corporate Training & Planning

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VISCOSITY INTRODUCTION: The variation in viscosity of the resin arises from the deviation in Viscosity of the resin. It is an indicator of working life of resin. It is important for achieving uniform impregnation and wetting of fiber during molding operation. It is determined by means of a viscometer that measures the torque produced on a specified spindle while rotating at constant speed when immersed in polymeric solution. DEFINITION: It is defined as the resistance to the flow due to internal friction. When one layer of fluid (resin) is caused to move in relation to another adjacent layer it causes the friction to the flow. Highly viscous resins requires more force to move than less viscous material Corporate Training & Planning

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VISCOSITY SIGNIFICANCE: It is useful for quality control of incoming raw material and to check batch-to-batch uniformity of resin. It is used for research and development of resin system curing agent etc. APPARATUS: Brookfield viscometer Model RVT with 8 speeds of 100, 50, 20, 10, 5, 2.5, 1.0 and 0.5 rpm. Spindles No. 1, 2, 3, 4, 5, 6 & 7 Constant temperature bath, Capable of controlling and maintaining a constant temperature of 23+ 2oC. Glass jars, Wide mouth glass jar of 10.8 cm high & 5.7 cm equipped with screw lids, jars etc. Thermometer, capable of measuring temperature of range of – 2 to + 52oC. CONDITIONING: Condition test sample at 23+ 2oC and % relative humidity for not less than 40 hrs prior to test. Corporate Training & Planning

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VISCOSITY PROCEDURE: Transfer test sample in a glass jar and attach the lid. Condition the resin samples in water bath for 2 hr + 5 min. at 23oC + 0.2oC. Select the test spindle and fit in to the Viscometer. Move the jar into the place under the spindle and adjust elevation of the jar so that the upper surface of the sample is in the center of the shaft indentation. Care is taken to keep the Viscometer immersed in the resin all time during the test. Set initial speed of a spindle at 0.5 rpm and allow the spindle is to rotate for about 8 or 10 revolution. The switch ON the spindle at higher speed of 10, 2.5, 5, 10, 20, 50, 100 rpm to stabilize the pointer. Take reading after 10 revolutions. The procedure is repeated until reading (each after 8 or 10 revolution) are constant within the scale division. Corporate Training & Planning

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VISCOSITY OBSERVATIONS Record the test temperature, time and dial reading of the viscometer in the centi poise and convert the result from the table. FACTORS AFFECTING VISCOSITY: Following factors affect the viscosity of resin. Proportion of reactants used in synthesis of resin, presence of impurities in resin, Storage condition such as temperature, humidity and duration etc. Corporate Training & Planning

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HARDNESS INTRODUCTION: The hardness of thermo-set resin is determined after curing of the resin and of reinforced composite when it has been fabricated and cured fully. Most commonly used methods for determination of hardness of cured resin and FRP are Rockwell and Barcol hardness as per ASTM D 785, ASTM D 2583 respectively. DEFINITION: Hardness is defined as the resistance to indentation, penetration, scratching and deformation particularly permanent deformation. SIGNIFICANCE: The extent of curing of resin is assured by hardness of cured resin and fiber reinforced plastic. It is useful for comparative evaluation and grading of material and also used for quality control of the cured resin and reinforced plastic. This test is also used as a tool of process control. Corporate Training & Planning

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HARDNESS EQUIPMENT: Following equipments are used for determination of hardness of resin and reinforced plastics. Rockwel Hardness tester with accessories for determination of Rockwell hardness. Indentors of various sizes ( ½”, ¼”, 1/8” , 1/16”, diamonds indentor) Standard Hardness block of known hardness value for calibration of equipment. Micrometer capable of measuring thickness to the accuracy of 0.01mm. Barcol hardness tester with accessories for determination Barcol hardness. PROCEDURE: The detailed test procedure of Rockwell, Barcol & Durometer hardness are given in the chapter Mechanical Properties. FACTORS AFFECTING: Hardness of the cured resin and reinforced plastics depends upon the rate and the extent of the curing. Higher is the extent of curing higher will be the hardness and vice-versa. It is also affected by the type of the resin and the hardener used. Corporate Training & Planning

INTRODUCTION: Gel-time and Peak Exothermic temperature are the important parameters for thermo-set resin. Resin producing high exothermic heat is more susceptible to cure shrinkage and craze cracking. The laminates, which experience high heat, built up (due to exothermic temperature) during cure of the resin it tend to produced weak inter-laminar bond between the layers which leads to poor physical properties of composite DEFINITION: GEL-TIME: It is the time interval between the introduction of catalyst in thermo set resin and formation of Gel. It is expressed in minutes. PEAK EXOTHERMIC TEMPERATURE: Peak exothermic temperature is the maximum temperature reached by reacting thermosetting plastic composition on incorporation of catalyst. It is expressed in degree Celsius. Corporate Training & Planning

SIGNIFICANCE: Gel-time helps to determinant working life of resin system on introduction of catalyst in the resin. Peak exothermic temperature provides information about the rate of curing of resin, hrinkage and craze-cracking likely to produce in reinforced plastics products. It is useful for quality control of the incoming raw-material ( i.e resin) and to check batch to batch uniformity. It helps to the processor to adjust their process according to gel-time of resin system. Peak exothermic temperature affect the inter-laminar bond of composite and hence physical properties of laminates. These tests are useful to ensure against storage changes and batch variations. Corporate Training & Planning

EQUIPMENTS: Following equipments are required. A simple container of approximately 7cm dia and 1.4cm depth A wooden probe and stopwatch A constant temperature bath capable of maintaining and holding temperature within ± 0.10 C Temperature measuring device capable of measure temperature to the accurately of ± 0.10 C, Non-conducting surface such as dry wood or corrugated casing etc. CONDITIONING: The test sample and other components are placed in suitable sample container and conditioned in controlled temperature at 23 0 C for 4 hours prior to testing. Probe to be used is also conditioned along with test sample. Each component of samples is agitated separately with a stirrer rod for about 3 minutes in such a way that air does not entrap. Corporate Training & Planning

PROCEDURE: Gel-time and Peak exothermic temperature is determined according to ASTM D 2471 by a common test. The conditioned sample compositions are taken and curator is added to the resin in the recommended ratio and stopwatch is immediately started. It is noted as starting time. The curator and resin is mixed slowly by agitating the mixture with stirrer rod or mixing paddle. All care is taken such that heat transfer from the sample container does not take place. Sample containers is placed on non-heat conductive surface such as wood. Thermo couple or suitable heat measuring device is inserted in the reacting mass. The change of temperature is observed and recorded at the end of test. When reacting material stops adhering to the clean probe that time is recorded as Gel-time as the elapse time from the start of mixing. The temperature and time recording is continued for determination of Peak Exothermic temperature. The highest temperature during reaction is recorded that is called peak exothermic temperature and time elapsed to reach peak exothermic temperature is called peak exothermic time Corporate Training & Planning

FACTORS AFFECTING: Following factors affect the Gel-time and Peak exothermic temperature of resin - Chemical composition of resins and proportions of reactant mass. - The type and amount of the curators a hardener used - Impurities present in the resin Corporate Training & Planning

In order to ensure high quality it is often required that certain feature of the chemical composition be determined. The presence of contaminants in resin can impair physical, chemical and electrical properties. For epoxy resin, tests of epoxide equivalent and hydroxyl content provide measures of the reactivity of the resin. Chloride and moistures of purity excessively values of such impurities can influences reactivity as well as the electrical properties of the end product. ASTM D 1652 is used for determination of epoxide content in the epoxy resin and ASTM D 1726 for chloride content in epoxy resin Acid number of un-catalyzed polyester is determined as the quantity of KOH required to neutralize 1gm of the resin. The acid number is used to ensure the batch uniformity with respect to reactivity. NON-VOLATILE CONTENT: Resin containing volatile species such as solvents etc. the determination of non-volatile (solid) content is often required. ASTM D 1259 described the determination of non-volatile content of resin solutions. Non-volatile matter are determined by weighing some amount of sample and then exposed for specified period of time and temperature and weights are measured before and after Corporate Training & Planning

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REFERENCES Hand Book of Plastics Testing Technology By Vishu Shah. Testing & Evaluation of Plastics By A.B. Mathur. Hand Book for Plastics Processor By J.A.Brydson. Hand Book of Plastics Test Method By R.P.Brown. IS Standards & AST Standards. Corporate Training & Planning

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