STUDY OF CUTTING TOOLS & JIGS FIXTURE

Submitted for partial fulfillment of award of BACHELOR OF TECHNOLOGY Degree In MECHANICAL ENGINEERING By  ANUJ KUMAR  ALOK SHARMA  DEVVRAT SINGH  S.M ARSHIL ZAIDI VIVEKANAND INSTITUTE OF TECHNOLOGY AND SCIENCE,GHAZIABAD UTTAR PRADESH TECHNICAL UNIVERSITY,LUCKNOW

 We hereby the declare the work being presented in this report entitled ” STUDY OF CUTTING TOOLS AND JIG FIXTURE” is an authentic record of our own work carried out under the supervision of Mr. “SUBHANKAR KARMAKAR”  The matter embodies in this report has not been submitted by us for the award of any other degree. Name of students  ANUJ KUMAR  ALOK SHARMA  DEVVRAT SINGH  S.M ARSHILZAIDI

1. INTRODUCTION 2. TOOL DESIGN METHOD 3. DESIRABLE PROPERTIES OF TOOLING MATERIAL 4. TOOLING MATERIAL AND HEAT TREATMENT 5. SELECTION OF TOOLING MATERIAL 6. TOOL GEOMETRY 7. CHIPS FORMATION 8. TYPE OF CHIPS 9. TOOL FAILURE AND TOOL CUTTING LIFE 10. EFFECT OF DIFFERENT PARAMETERS ON TOOL LIFE 11. IMPORTANCE OF JIG FIXTURE 12. MANUFACTURING OF HAND VICE 13. CONCLUSION

 This project deals with “STUDY OF CUTTING TOOLS AND JIGS FIXTURE” with an aim of increasing the tool life. Various factors play an important role in deciding the tool life such as Geometry of tools, tool material, machining operations, types of coolant used and cutting environment etc.  This project describes the tool design procedures, various tool materials, selection of appropriate tool for machining operations and explains the reasons for tool failure. It also describes the factors for increasing the tool life.  This project also completely explains the various types of “JIGS AND FIXTURES” how they are manufactured, principle of location, their specifications & their importance.  The project also includes manufacturing of “HAND VICE”.

1.Statement of the problem  Why the tool is needed?  What are the required capabilities of the tool  The type of machine the tool must be used on  The number of the part to be produced  Other pertinent information concerning the part.

2.The need analysis  Will the tool used by the skilled or unskilled operators?  How many parts can be held on the tool?  What are the hole-location tolerances on the part?  What provisions are to be made for coolant  Is the cutting force heavy or light?  Etc.

3.Research and the ideation(sketches)  Dimension of the part to be held or produced  Kind of the material from which the part is made  The tolerance of the part  Dimensions of the machine  Limitations of the machine  Amount of the tonnage to blank the part.

4. Tentative design solutions 5.The Finished Design

 Strength:  Plasticity:  Elasticity and stiffness:  Elastic limit:  Toughness:  Hardness:  Machinability:  Endurance limit:  Cost:

 High carbon steel  High speed steel(HSS)  Coated high speed steel  Cast alloy  Cemented carbides  Non-Tungsten Cemented Carbides  Ceramics (Cemented oxides)  Kyon  Sialon(Si-Al-O-N)  Boron Nitride  Diamond  Polycrystalline Diamond (PCD) and Solid Film Diamond (SFD)

 Normalizing:  Annealing:  Spheroidizing:  Hardenability:  Stress relieving:  Stabilizing:  Hardening:  Pack hardening:  Quenching:  Tempering:  Double tempering:  Decarburization:

 Single carbide steel-Machining grey cast iron,brass bronze etc  Composite carbide -Machining Steel

Cemented Carbide

Cemented carbide

MILLING CUTTER

All machining processes involve formation of chips by deforming the work material on the surface of the job with the help of the cutting tool.

(a) tightly curled chip; (b) chip hits workpiece and breaks; (c)continuous chip moving away from workpiece; and (d) chip hits tool shank and breaks off.

 Continuous chips During the cutting of ductile materials like low carbon steel, copper, brass etc., a continuous ribbon type chip is produced. The pressure of the tool makes the material ahead of the cutting edge deform plastically.

Continuous chips with built up edge The temperature is high at the interface between the chip and the tool during the cutting. Also, the work material slides under heavy pressure on the rake face before being transformed into a free chip. In these conditions, some portion of the chip may stick to the rake face of the tool. Because of such a close contact, it discharges its heat to the tool and attracts more of the deforming work material and thus the size of “built up edge” goes on increasing and breaks up after a critical stage.

 Discontinuous chips These chips are produced during the cutting of brittle material like cast iron, and brasses. Even a slight plastic deformation produced by a small advance of the cutting edge into the job leads to a crack formation in the deforming zone.

MECHANISM OF TOOL WEAR 1.Adhesion 2.Abrasion

MECHANISM OF TOOL WEAR 3.Diffusion 4.Oxidation

SOME TOOL FAILURE; 1.Flank wear- VB=0.3mm; VBmax=0.6mm. 2. Fracture failure. 3. Temperature failure 4. Gradual wear 5. Crater wear- KT = f, where f is the feed per revolutions 6. Plastic Deformation 7. 2 Mechanical Breakage

Taylor’s Empirical Equation: VT n =C Where, T = tool life time; usually in minutes V = cutting velocity, m/min C = constant; the cutting velocity for 1 minute of elapsed time before reaching the wear limit of the tool n = constant which is considered a characteristic of the tool material, called tool life index. Typical Tool Life Exponential Graph

Modified Taylor’s Equation This incorporates the feed rate and depth of cut having their own index X and Y where the indexes are obtained experimentally. Typically from machining practices these values can be taken as: n=0.15, x=0.15, and y=0.6 (typical values) VT n d x f y = C The above equation may be rewritten for determining the time as shown: T=C 1/n V -1/n D -x/n f -y/n

Optimum Cutting Speed

Effect of Varying Rake Angle

Influence of Feed Rate on T.L

Influence of Tool Shape on Cutting Speed and Tool Life

Influence of speed and feed on the economics of MRR

Relationship between the specific wear rate and tool temperature

 To hold the Work Piece  To guide the tool (jigs)  Protects the tool from accidental failure  Better productivity  Automates the machine tools  Ensures machining accuracy  Less skilled labor can be used

The manufacturing of hand vice is done with an aim of practically examining all the factors involved in various machining operations, that we have studied in our project. All the factors were carefully studied with an approach to increase the tool life for e.g tool geometry, tool material, temperature, cutting fluid, and proper use of jigs & fixtures etc.

ParameterInfluence and interrelationship Cutting speed, depth of cut, feed Rate, cutting fluids. Tool angles Continuous chip Built-up-edge chip Discontinuous chip Temperature rise. Tool wear Machinability Forces power, temperature rise, tool life, type of chips, surface finish. influence on chip flow direction; resistance to tool chipping. Good surface finish ; steady cutting forces ; undesirable in automated machinery. Poor surface finish, thin stable edge can product tool surface. Desirable for ease of chip disposal ; fluctuating cutting forces ; can affect surface finish and cause vibration and chatters. Influences surface finish, dimensional accuracy, temperature rise, forces and power. Related to tool life, surface finish, forces and power

ParameterInfluence and interrelationship Selection of machining process Selection of tool material Cutting environment Selection of proper jigs and fixture Accuracy of machine Vibration in machine Right machining process minimize the tool wear,& gives better tool life. Selection of tooling material is most important factor. Tool material always should have higher strength then the material to be cut. Tool life is also depend upon the right jigs/fixture is used. They minimize the accidental tool failure & gives the direction to tool. Accurate machine have low tool wear rate. Vibration in machine increase the tool wear.

ParameterInfluence and interrelationship Mechanical properties of tool material chemical properties of tool material Selection of cutting fluid Proper heat treatment Coating Material Skill of workers Tool life is directly depend upon the mechanical properties of tool material Oxidation decrease the tool life A proper cutting fluid can increase the tool life uptu 20% A heat treated tool can with stand higher temp.& have longer tool life A proper Coated material can increase the tool life uptu 300% Skill worker have better knowledge of cutting process & machine operation

ParameterInfluence and interrelationship Proper Methods of Applying Cutting Fluids

ParameterInfluence and interrelationship Proper heat treatment Coating Material Skill of workers A heat treated tool can with stand higher temp.& have longer tool life A proper Coated material can increase the tool life uptu 300% Skill worker have better knowledge of cutting process & machine operation

Thank you