Lecture 13 Single Knit Machines (plain)
Main Products Single Jersey Pique Locast Honey comb Pique fleece Two thread fleece Feed stripes
Single Knit Machine Working Single bed of needle Only cylinders Needles and sinkers High speed Wider width Most common Easy to handle
Double Knit Machines Cylinder and Dial Two bed of needles No sinker Double side knitting
Sub types Interlock Rib Double jersey (interchangeable)
Interlock Highly flexible fabric Can adopt any body shape Used for under garments Soft hand feel
Lecture 13 Knitting Accessories Compressed air Lubricants Air conditioned Yarn storage Fabric Storage
Compressed Air For Cleaning Oiling Fluff removing
Parameters of Compressed Air Cool Dry Required pressure Required quantity
Sources Compressors Piston based Screw Base
Cooling Process Refrigerator technology Cooling towers Best is refrigerator technology
Lubricants Main purpose is lubrication to reduce friction between parts of machines, particular between needles and cams
Parameters of Lubricants High lubrication Easy wash during wet processing No smell No stain Normally called white oil Supplied by all big companies Some chemical manufacturers add some auxiliaries in it
Air Conditioning of the hall Main objectives: Low temperature to keep machines cool Control of fluff Healthy environment Strength consistency of yarn Smooth running of machines Less wear and tear of machine High speed of machines Less breakage of needle and sinkers
Storage To avoid mixing Better look after Less wastage in transportation Easy to locate Controlled inventory
Lect 14 Knitting Calculations
Lecture 15 Fleece Fabric A fabric made by sheep wool, soft warm A fabric soft , warm bulky Generally used to: Protection from cold Sweat absorption (sweat shirt) Baby clothes
Fleece --- A fabric knitted with two types of yarn. Fine yarn is on front side and course yarn on back side. In most of cases fine yarn is 100% cotton while course yarn is P/C 50:50 Normal combination and fiber ratio: 30/16, 20/10, 26/12 etc PC/C, C/PC
Types of Fleece Two thread fleece Three Thread Fleece
Two thread Fleece Very rare Was popular when three thread fleece were not common Generally not liked due to impassion of course yarn on front side Low quality product
Conti--- Made on single jersey machines Maximum medium weight, since very course yarn difficult to use Long loop is difficult
Cam Arrangement On Fleece fabric.docthree needle track machine:
CHARACTERISTICS OF TWO THEAD FLEECE Light to medium weight Double impact on front side, particularly in case of different fibers No good brushing possible due to short length of loop
Three Thread Fleece Made on fleece machines High grammage is possible( 500 GSM) High brushing due to long loop on back side Maximum course yarn is possible ( up to 10 count) on back side Very common in use Fleece machine guage is 16 or 18
Yarn C/PC PC/C 30/16, 22/12/ 20/10
Cam Arrangement
Fiber Percentage Calculation Method Example: Front yarn 30s 100% cotton Back yarn 16 s 50:50 P/C Consumption ratio Front Two kgs Back one kg
Conti--- Total consumption three kgs Calculation: front yarn 2 kgs 100 % cotton Back yarn 1 kg ( ½ Kg polyester and ½ kg cotton Total Cotton consumed 2 + 0.5 =2.5 Kgs Total polyester consumed ½ kg Ratio: cotton= 2.5/3*100= 83.33% Polyester= 0.53*100=16.66% Such ratio is normally called 80:20 Fleece
Main characteristics of Three Thread Fleece Highly absorbent High weight is possible Can use entirely different yarn on both sides( even dyed yarn) Pattern is possible ( diagonal stripes etc) Very common in use
Fleece problems and their remedies Uneven loop – control yarn supply Loop stretch– control cam tension Needle line on front side Wales thickness variation on front side due to fluff contamination between the needles, needs regular cleaning, more cleaning is required due to course yarn
C-- Poor brushing–due to high TPI yarn– use low TPI Dyeing variation due to different percentage of yarn… calculate exact % by using Skelton test Steak problem after dyeing due to heavy weight fabric--- use anti creasing agents in dyeing
C--- High shrinkage --- use compactor or tumble dryers
Other types of fleece Sherpa fleece --- brushed and washed to get balls Polar fleece ---- loops on both sides also brushed on both side
Loop knits Terry fabric to knitted terry towel
Good luck, May Almighty bless you
Knitting Costing Objectives of the session: To make participants familiar with the basic terms of costing To create an understanding about the costing methods To develop a skill to do costing in a Knitting department
Basic Cost Terms and Concepts Different Costs for Different Purposes Fixed and Variable cost Cost Drivers Direct and Indirect Cost Controlled and Uncontrolled cost Direct material Direct Labour
Continue… Manufacturing Overhead Indirect material Indirect labour Other Manufacturing Cost Service department Overtime Premium Idle Time Conversion Cost
Cost Flow in a Manufacturing Company Direct Material Direct Labour Manufacturing Overhead
Economic Characteristics of Cost Opportunity Cost Out of Pocket Cost Sunk Cost Differential Cost Incremental Cost Margin Cost Average Cost
Cost and Benefit Information
Job Oriented Cost System Product Costing
Types of Product Costing Job-Order Costing System Process Costing System
Activity Based Costing (ABC) Stage One Overhead Costs are assigned to activities Overhead Cost are assigned to production job
Knitting Cost Process Cost Job-Order Cost
Process Cost Material Labour
Material Direct Yarn Lubricants Machine Accessories Needles Energy
Continue… Indirect Engineering Department Other Service department
Labour Direct labour Worker Technical people Managers Accounts
Indirect labour Marketing people Accounts People Finance People Others
Overhead Administration Financial Cost Marketing Cost
Knitting Department Costing is based on Process and as well as on Job Order Process Based Costing Knitting is main process
Continue… Material Main Cost is of yarn Yarn Consumption Yarn wastages Yarn Running Properties Yarn Package sizes
Continue… Other material Machine Accessories Needle s--- Breakage depends upon yarn quality Lubrication depends upon yarn quality
Labour Different Production for Different yarn and fabric qualities Different production for different customers Different Production in different seasons Requirement of number of workers is different
One Practical Example Labour Cost Department of 20 machines Staff One Knitting Manager and one assistant along with three shift in charges Three Shift production 5000 kgs per day @ 145 per kg
Continue… Salary Bill KM 30000 Assistant 15000 Shift In charges 30000 Labour 180000 Other Staff 25000 Total 270000
Material Consumption Yarn 5600 Kgs Yarn price 125 per kg Needles 100 per day Needles 40000 per six month Sinker 40000 per six month Machine oil 10 kg per day Parts 200,000 per annum
Prices Needles Rs. 35 per needle Sinker Rs. 20 per needle Oil Rs 120 per kg Machine Price Rs. 2.5 million per machine Depreciation 10 % straight Financial cost 7.5 % per annum Total project cost 85 Million
Calculate: Cost per kg with the current data Fixed and variable cost Break Even point in Rs and in Kgs Project pay back period BE( pcs) F/P-V BE $ F/1-V/P
Time Cost Concept Per hour factory cost Per month factory cost
Cost improvement strategy Minimum fixed cost Less wastage High efficiency Low idle time Maximum utilisation of machines
Role of Knitting in Dimensional stability of Knitted Fabrics Resistance to change in area
May be negative or positive Change in the Area May be negative or positive
Textile Raw Material Spinning Knitting Wet Processing Stitching Reason: Textile Raw Material Spinning Knitting Wet Processing Stitching
Change Wanted? Unwanted? Wanted in case of bandages Some time in fitted garments Unwanted in case of garments
Can We Have Zero Shrinkage Garments Yes…but with many ifs and buts Normally Cannot Have to live with tolerance
Tolerance Limits: Depends upon: Textile raw material Yarn Count Knitting Structure
Mechanisms of Shrinkage Swelling of fibers If there is no swelling then there is no shrinkage ??????? Elongation of fibers No elongation no shrinkage????? Recoverable Elongation High Recoverable Elongation no shrinkage ?????
Shrinkage Concept needs some clarification --- due to swelling--- needs more lengthy path to travel ---kept in stretched form ---needs to be in natural form ---kept in pressed form ---needs to be in natural form
Other Factors--- ---space between loops and wales to move ---high tension during feeding --- residual energy ---mixture of fine and course yarns
How knitting department can help in shrink controlling? Yarn Twist Yarn Tension Knitting structure--- is not in the control of knitter, it depends upon designer Proper combination of yarn count and machine guage Uniform yarn feeder tension Uniform and appropriate fabric take up tension
Total Productivity Management What is productivity? Doing more with less Productivity is an approach, a mindset, and a way of thinking to do more with less
Why productivity? Increase output increase productivity Profit and productivity are synonymous Cutting cost improve productivity Profit today and tomorrow are possible Partial productivity improvement is worthwhile Productivity only applies to production
When Productivity? v High competition, survival is based upon the right balance between price quality and delivery v Manufacturing industry has been redistributed to include the third world. v The economic and social well being of people, and in turn the peace of the world, depends organisation of all kinds making effective use of the limited resources. v There is a huge need of funds for education, health and other services. It is the duty of the business organisations to mange their productivity more effectively to fulfil these needs. The undesirable effects of inflation can be reduced by the efficient production
Conti… Productivity becomes a crucial issue when there is a scarcity of resources.
TPM and Knitting Resource utilization Minimum wastage Maximum output Invention in methods Controlling and preventions Improve contributing factors
Inputs in knitting Yarn Machines Machine spare parts Machine accessories Labour hours Financial cost Department per hour cost
Outputs: Knitted fabric Revenue from knitted fabric Profit= Rev-cost
TMP CYCLE Measure Evaluate Plan Implement
How it is measured? Documentation Calculation Monitoring
How it is evaluated? Compare With? Competitors Industry Sellers claims Previous records
How to plan it? SWOT analysis Trend analysis By regression analysis Think new ways Involve every one Group responsibility Incentives Celebrate the minor success plot on graphs
Implement? With full confidence of positive results
Achievements High production Low knitting faults Low consumption of accessories Low wear and tear cost Less down time In time deliveries more profit More employment
Benefits of High productivity Only one way of survival
Quality control in knitting
Before Knitting Yarn Machine Needles Sinkers Oil
Yarn Before knitting Count Weight Winding Cone shapes Packing
After Making samples Yarn variation Patta (Barrenness) Thick and thin places Dead cotton Knots Strength Cotton color
Machine Gauge Working condition Automation Safety measures Spare parts
Needles and sinkers Quantity Quality Spare Working conditions
Quality of knitted fabric Knitting is a irreversible phenomenon Checking can only intimate and no repair is possible Only it can help in prevention
Checking Method 100% checking of knitted fabric Report is made Report is presented to managers Action is taken Pass fail decisions are made
Point system Four point system is used, which is not useful Rather checking should be on number of faults Strong coordination is required between quality and production people