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SMEDA-JICA INDUSTRY SUPPORT PROGRAM

BEST PRACTICES MANUALKNITTING SECTOR

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Small and Medium Enterprises Development AuthorityMinistry of Industries and Production

Government of Pakistan

www.smeda.org.pk

SMEDA-JICA Industry Support Program Best Practices Knitting Manual

ACKNOWLEDGEMENT

This manual has been prepared under the SMEDA–JICA Industry Support

Program. With the courtesy of Government of Japan and JICA (Japan

International Co-operation Agency), this program has been started in Pakistan for

the support of Textile Industry. The objective of this program is to provide

expertise, knowledge transfer and skill up-gradation for the enhancement of

productivity, efficiency and to give know how to local industry for better

management practices.

Senior Japanese Knitting Expert Mr. Takao MIYAZAKI offered his services as

Senior Volunteer for Knitting Sector of Pakistan for a period of two years. During

this period Mr. Takao MIYAZAKI has provided guidance / consultancy to

various industrial units.

This manual highlights the main areas where the guidance was provided in

different industrial units. This includes key findings, process details, important

recommendations / suggestions and recommended formats. It has been prepared

by Mr. Muhammad Ayaz & Mr. Adil Nazir Malik of Industry Support Cell,

SMEDA and reviewed and checked by Mr. Takao MIYAZAKI.


TABLE OF CONTENTS

AREAS IDENTIFIED AND RECOMMENDATIONS……………………………...…………11 Production Control .......................................................................................................... 1

1.1 Production Targets for Feeders Machine .......................................................... 11.2 Actual Production for Auto Striper Machine..................................................... 31.3 Knitting Program Chart .................................................................................... 41.4 Data Chart for Knitting Condition .................................................................... 41.5 Knitting Machines Daily Efficiency ................................................................. 51.6 Production Analysis Graph............................................................................... 61.7 Setting of RPM ................................................................................................ 71.8 Humidity and Temperature............................................................................... 71.9 Traceability of data........................................................................................... 7

2 Quality Control................................................................................................................ 82.1 Yarn Knotting .................................................................................................. 82.2 Handling and Storage of Fabric Roll................................................................. 82.3 Graphical Representation of Defects................................................................. 82.4 One Feeder Tube Knitting Machine.................................................................. 82.5 Yarn Tension.................................................................................................... 92.6 Yarn Eye Guides .............................................................................................. 92.7 Creel Pipe Position ........................................................................................... 92.8 Yarn Passage.................................................................................................. 102.9 MPF Tension Washers ................................................................................... 102.10 Damaged Paper Cones.................................................................................... 102.11 Slub Catcher Gauge........................................................................................ 102.12 Bar (Patta) Line.............................................................................................. 112.13 Press off Problem ........................................................................................... 112.14 Methods to Control Winder Lines .................................................................. 122.15 Oil Stains ....................................................................................................... 132.16 Spot Marks on Fabric Surface ........................................................................ 132.17 Double Stitch Problem ................................................................................... 132.18 Air Circulation System................................................................................... 142.19 Separating & Covering the Knitting Machine ................................................. 142.20 Method of Checking Greige Fabric GSM ....................................................... 14

2.20.1 Guidelines for Checking of GSM .................................................................. 152.21 Stitch Length of Fabric Sample ...................................................................... 152.22 Calibration of Round Meter............................................................................ 152.23 Measuring Actual Stitch Length ..................................................................... 152.24 Fabric Inspection............................................................................................ 162.25 Analysis of Inspection Sheet Machine Wise ................................................... 172.26 Yarn Inspection .............................................................................................. 182.27 Use of Compact Yarn..................................................................................... 182.28 Fabric Stability and Finished Width................................................................ 19


3 Machine Maintenance.................................................................................................... 203.1 Machine Maintenance Schedule ..................................................................... 20

3.1.1 Daily Maintenance ......................................................................................... 203.1.2 Weekly Maintenance...................................................................................... 213.1.3 Monthly Maintenance..................................................................................... 213.1.4 Bi-Annual Maintenance.................................................................................. 223.1.5 Annual Maintenance ...................................................................................... 223.1.6 Machine Overhauling ..................................................................................... 22

3.2 Lubrication..................................................................................................... 223.3 Sinker Timing Gauge ..................................................................................... 233.4 RPM Meters and Counter Meters ................................................................... 233.5 Machine Cleaning .......................................................................................... 233.6 Needle Life .................................................................................................... 243.7 Needle Break Data ......................................................................................... 243.8 Operator Responsibilities ............................................................................... 243.9 Analysis of Machine Stoppages...................................................................... 25

4 Cost Control .................................................................................................................. 264.1 Yarn Waste .................................................................................................... 264.2 Oil Leakage.................................................................................................... 264.3 One Operator for at least Two Machines ........................................................ 274.4 GSM Measurement ........................................................................................ 274.5 Individual Work Order Closing Report........................................................... 27

5 Fabric Development ...................................................................................................... 285.1 Stitch Length of Fabric Sample ...................................................................... 285.2 Determination of Count/ Denier of Given Yarn .............................................. 285.3 Actual consumption of yarn............................................................................ 295.4 Ratio of Cotton to Lycra Feed ........................................................................ 32

5.4.1 Finding the Percentage of Lycra ..................................................................... 325.5 Determination of Finish Fabric Gauge............................................................ 345.6 Setting of GSM in Greige Fabric .................................................................... 365.7 Knitting process ............................................................................................. 36

5.7.1 Analyze the Sample........................................................................................ 365.7.2 Development of Knitting Specification........................................................... 37

5.8 Knitting Construction and Layout Graph ........................................................ 375.9 Use of 1/1000 Gm Graduation Scale............................................................... 375.10 Knitting of 100 % Polyester or 100 % Lycra .................................................. 38

6 Useful Calculations........................................................................................................ 396.1 Calculating GSM of Swatch ........................................................................... 396.2 Calculating Length from Fabric Weight.......................................................... 406.3 Conversion Formulas for Cotton Count and Polyester Denier ......................... 406.4 Formula for Finding Gauge of the Yarn Count ............................................... 416.5 Calculations for Finding GSM........................................................................ 42


7 5 S (A Japanese Management Technique) ...................................................................... 447.1 How to Practice 5S......................................................................................... 45

7.1.1 Seiri ............................................................................................................... 457.1.2 Seiton............................................................................................................. 467.1.3 Seiso .............................................................................................................. 477.1.4 Seiketsu.......................................................................................................... 477.1.5 Shitsuke ......................................................................................................... 48

8 Fish Bone Theory .......................................................................................................... 498.1 Identify the Problem....................................................................................... 498.2 Work out the major factors involved............................................................... 498.3 Identify Possible Causes................................................................................. 508.4 Analysis your diagram.................................................................................... 50

9 Employee Participation & Training................................................................................ 519.1 Employee Training .................................................................................................... 51

ANNEXUREAnnex-I: Knitting Program Chart54Annex-II: Data Chart for Knitting ConditionsAnnex-III: Machine Counter StatusAnnex-IV: Production Analysis GraphAnnex-V: Machine Wise Inspection ReportAnnex-VI: Machine Maintenance ScheduleAnnex-VII: LubricationAnnex- VIII: Knitting Construction GraphAnnex-IX: Fish Bone Chart


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AREAS IDENTIFIED AND RECOMMENDATIONS

1 Production Control

1.1 Production Targets for Feeders Machine

Daily production targets should be defined on the basis of production capacity of

the machine. There is a 20 round method to measure the actual production capacity

of the knitting machines. In this method, the weight of the fabric produced for 20

rounds is taken and the production is calculated in a kilogram which is based at 100

percent efficiency by using the calculations explained below.

On the basis of this value, the actual efficiency of the machine and corresponding

production target may be defined.

The following is the procedure of the experiment that needs to be conducted on the

knitting machine:

Run the machine for 20 rounds and produce the fabric

Cut the 20 round fabric from the roll. If possible, a colored yarn can be used

to identify the fabric produced in 20 rounds

When cutting this fabric from the roll, handle it carefully

Now immediately place this fabric on the table in relaxed state and measure

the length and width of the fabric

Weigh the fabric

Using this data, calculates the production target as follows:

Fabric Width = (cm)= /100 (m) ……. (1)

Fabric Double Width = (1) × 2 (cm)

= /100 (m) ……. (2)

Length of Fabric produced in

the 20 rounds (cm) = /100 (m) ……..(3)

Weight of Fabric produced in 20 rounds = (gm) ...….. (4)


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Weight of One Round Length

(4) / No. of rounds = ...…... (5)

Meter Weight (4) / (3) (gram / meter ) = ...........(6)

GSM (6) / (2) = gram / meter 2 ...........(7)

Production Calculation (on 8 Hours basis):

Production for 100% Efficiency

= Machine R.P.M × 8 hours × 60 minutes x (5)

= (Fabric Weight in Grams)

= (Fabric Weight in Grams) / 1000

= (Fabric Weight in Kilo Grams) ……. (8)

This will be the weight of fabric produced at 100% efficiency at that particular

machine in 08 hrs. Similarly, the 100% production in 12 hrs or 24 hrs can be found.

Production @ 85% Efficiency

In order to set the production target for the knitting machine, multiply the 100%

production value with the desirable efficiency (in our case we took it 85 %)

= (8) x 0.85

= Kilo Grams ……… (9)

This (9) will be the production target based on the actual conditions.


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1.2 Actual Production for Auto Striper Machine

The actual production of Auto Striper machines is calculated in kilograms at 100

percent efficiency by using the calculations explained as below.

A = No. of Courses

B = No. of Courses

C = No. of Courses

D = No. of Courses

E = No. of Courses

Rounds of X Pattern Repeat

= (A+ B+C+D+E+……) × No. of Repeat

No. of Feeders

Fabric Width (cm) = (m) ……… (1)

Fabric Double Width (cm) = (m) ……… (2)

Length before cutting of X Pattern Repeats = (m) ……… (3)

Weight after cutting of X Pattern Repeats = (g) ……… (4)

Weight of One Round Length = (4) /Rounds of X Pattern Repeat … (5)

Meter Weight (4) / (3) (gram / meter) = ……… (6)

Production Calculation (on 8 Hours basis):


= Machine R.P.M × 8 hours × 60 minutes x (5)

= (Fabric Weight in Grams)

= (Fabric Weight in Grams) / 1000

= (Fabric Weight in Kilo Grams) ……… (8)


= (8) x 0.80

= Kilo Grams


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1.3 Knitting Program Chart

A knitting program chart should be attached on each machine. This will help to

provide complete view of the existing work order running on the machine (Format

is attached in the annexure-I).

The knitting program chart should include the following points:

Machine No.

Work Order No.

Machine Type

Machine Gauge /Dia

Machine RPM

Yarn Brand

Yarn Count

Fabric Type

Slitting Line Y/N

Stitch Length

GSM

1.4 Data Chart for Knitting Condition

Whenever, starting the new article it is appropriate to make a data chart (attached in

the annexure-II). This chart will help to have complete information about that

article and will be used for future reference. The implementation of this process will

reduce the wastage of time whenever a repeat order is requested. This will also

make the working easier and any problem that encountered during the production of

a repeat order can easily be solved.

Following information should be included in the said data sheet:

Machine Number

Design

Yarn Count

Stitch Length


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Round Meter

Tension

Sinker Timing / Needle Timing

Feeder Position.

IRO Tape.

Number of teeth of MPF tape

Greige GSM

Finish GSM

Problems encountered during production of the article

Possible solutions of problems

Swatch of the Fabric

1.5 Knitting Machines Daily Efficiency

For calculating the actual efficiency of machines and operators (shift wise & on

daily basis), a counter status check method is suggested (Format is attached in the

annexure-III). This counter status check is used to determine the actual production

shift wise. The following example illustrates the method to calculate the actual

efficiency:

For example:

I. M/C No. = 1

II. Work Order No. = 1685

III. RPM (Round Per Minute) = 20

IV. Total No. of Hours of One Shift = 8

V. Counters Required to Knit One Roll = 1900

VI. No. of Rolls Produced in One Shift = 3

VII. Total No. of Kilograms Produced in One Shift = 105

VIII. Counters Received from the Previous Shift = 1100

IX. Counters Forwarded to the Next Shift = 1000


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So, the Total actual rounds (counters) in the shift will be:

= (VI × V) + IX – VIII

= (3 × 1900) + 1000 – 1100 = 5600 Rounds

But as per the speed (rpm) 100% rounds should have been

= IV ×60 × 20 = 9600 Rounds

The Machine Efficiency can be found as follows:

= 100 x Actual Rounds /100% Rounds

= 100 × 5600 / 9600 = 58.33%

Following is the Format to calculate the efficiency of machine

M/C # W/O # RPM Weight Counters Rolls C. Rec C. Lft Ttl 1 Shift %

1 1685 20 105 1900 3 1100 1000 5600 9600 58.33

1.6 Production Analysis Graph

Graphical representation of the data is very useful to analyze and monitor the trend.

Therefore, production data should be represented graphically to analyze the

production trends. It indicates the low production values and helps to take

immediate actions for production improvement. (Graph is attached in the annexure-

IV).

This graphical representation of production data will help to effectively control the

production activities and to achieve the desired production targets.


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1.7 Setting of RPM

Every knitting entrepreneur wants to know the ideal speed of the knitting machine.

But it is very difficult to determine an ideal speed (rpm) even for particular design

and machine itself. It differs with the yarn quality as well as the machine condition.

Therefore the optimum speed of machine may be set after experiments.

1.8 Humidity and Temperature

The humidity and temperature in knitting department should be 60± 5 % and 25± 5

°C. However during dry season when the outside humidity level falls, humidification in the

department needs to be controlled more efficiently. Maintaining required humidity level

improves the performance of knitting machine without affecting the metallurgy of the

machines.

1.9 Traceability of data

If reports and filing system are not managed properly, it creates difficulty to monitor

the trends. Therefore it is necessary that the reports and filing system should be

managed properly.


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2 Quality Control

2.1 Yarn Knotting

Whenever yarn breaks or finished, it should be knotted instead of twisting as this is

normal practice used in industry. Because, in case of twisting it is likely that it may

open and may cause cut in the fabric. It is also one of the ways to reduce the cut in

the fabric.

During yarn knotting, the operator should use scissor / clippers for cutting the extra

knot edges. The extra knot edges should not be more than 5 mm in lengths.

2.2 Handling and Storage of Fabric Roll

Fabric roll should not be placed on the floor as it causes oil marks on the fabric. A

clean plastic sheet may be used to place the fabric roll on the floor. Also place

plastic sheet over the stored rolls to avoid accumulation of fluff on the fabric.

2.3 Graphical Representation of Defects

Graphical representation of fabric defects is very useful to analyze the quality.

Fabric defects should be represented graphically to easily monitor the quality and

take necessary corrective actions for each machine. Data recording in tabular form

is not easy to analyze whereas, graphical representation makes easier to view the

trend. Also, it is useful to find out the most recurrent faults.

2.4 One Feeder Tube Knitting Machine

The quality of incoming yarn can be easily monitored using one feeder tube knitting

machine. Another model of this machine is available with a creel for testing more

then one yarn cones automatically.


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2.5 Yarn Tension

Yarn Tension plays an important role in the knitting. It should be set properly at

start of each order and monitored as well. Yarn tension meter should be used to set

the yarn tension. The tension calculating formula for all type of yarns is:

Grams = 5315 / S (Count) × 20

This provides the starting guidelines for tension setting which can further be

adjusted by experimenting.

Variation in tension of yarn occurs due to improper winding. The following should

be taken care of:

MPF washer spring adjustment

Slow vibration of stopper

Presence of yarn eye guides (feeder, pipe, creel) on all machines

Replacement of damaged pipes

Even yarn wrapping on MPF (Main Pully Feeder)

2.6 Yarn Eye Guides

All yarn eye guides (feeder, pipe and creel) play an important roll in knitting

process. Missing yarn eye guides cause variation in yarn tension and high friction

hence affecting smooth flow of yarn. This also results in yarn breakage, knitting

holes and more fluff in the department. Therefore, missing eye guides must be

checked at regular intervals and replaced accordingly.

2.7 Creel Pipe Position

An improper position of creel pipe affects the yarn tension and thereby affecting

machine efficiency and increase fabric faults. Therefore, the creel pipe position

should be properly adjusted for smooth flow of yarn and damaged pipes should be

replaced with new ones. Also position of ring guides on creel should be at the

centre of paper cone tip.


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2.8 Yarn Passage

Yarn passage should be as smooth as possible. It should not touch any part of the

machine other than guides. Similarly, the correct passage of yarn should be

followed. If yarn touches any part of knitting machine other than guides, it will

increase the hairiness in yarn due to rubbings. It will also affect the yarn tension and

affects the machine efficiency and increase fabric faults (Knitting holes). To

overcome this problem, appropriate adjustment in the position of MPF should be

made.

2.9 MPF Tension Washers

MPF tension washers play an important role. As the name shows, MPF tension

washers control the yarn tension. If MPF tension washer is out of order or missing,

it will cause variation in yarn tension and high friction hence effecting smooth flow

of yarn. This also results in yarn breakage and fabric fault especially in fine yarn

count. Therefore, missing MPF tension washers must be checked at regular

intervals and replaced accordingly.

2.10 Damaged Paper Cones

If paper cones on the creels are damaged, it causes yarn breakage during unwinding

from these cones. It happened if the yarn suppliers is using paper cones of poor

quality and/or also care is not being taken during transportation and material

handling. The mill management must complaint the supplier if damaged cones are

received. Also, handling of yarn should be improved while loading / unloading as

well as placing on the knitting machine.

2.11 Slub Catcher Gauge

The following slub catchers are recommended to use:

0.4 mm slub catcher for 59/s and above count

0.6 mm slub catcher for 24/s to 39/s


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2.12 Bar (Patta) Line

Bar line is a major fault on the knitting machine. Bar line is basically appears due to

yarn tension variation or due to yarn quality. These are following steps for analysis

of bar line:

Take a piece of fabric from the defected portion

Marked length of 60 centimeters on both sides of fabric for analysis

Take out some yarns and find out the average length of yarns

If yarn which is creating bar line have same length as compare to other yarns.

This shows that the bar line may be appearing due to mixing yarn lot or using

different yarn count

If the stitch length of all yarns is not same then it will be the fault of yarn

tension

To control Patta in knitted fabric due to yarn tension variations, detect the feeders

where the Patta is visible and find out the respective feeders. Then keep on

changing the position of the cones on the creel till no such effect is visible.

2.13 Press off Problem

Press off is another problem being faced in knitting department. Press off problem

is basically a yarn breakage and it results due to the bad quality of yarn. During

knitting of fabric yarn break from feeder appears in the fabric as press off because it

broke after sensor.

To control the press off problem, the better quality yarn should be used and yarn

tension variation should be controlled on the knitting machine. The following points

will help to reduce the press off problem:

It should be ensured that passage of yarn is proper. It should pass from all

yarn eye guides and also should not touch with any other part on the knitting

machine


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All missing yarn eye guides should be checked at regular intervals and

replaced accordingly. Otherwise, yarns tension variations will result in press

off

The tension of all yarns should be set equal

The professional style of knotting should be adopted and operators should

use scissor for cutting extra knot edges

Fluff should be removed from machine and especially from feeders. Fluff in

feeders creates tension variation in yarn and increase the possibility of yarn

breakage

2.14 Methods to Control Winder Lines

Winder line is another problem of knitting. Following are the guidelines to control

the winder line:

Fastening woven fabric on the both ends of nip roller.

Ensuring minimum possible tension pressure on the fabric during winding.

Plaiting in a box.

Edge of the fabric from both sides should be made free by creating groove

on the nip roller

Slightly lower down the frame of fabric on knitting machine.

Changing the design of frame with Cadaratex frame (Fukuhara).

Slightly moving the winder line at inspection machine during inspection

The storage time of fabric should be as minimum as possible specially in

case of lycra fabric

Also, in dyeing department the fabric should not be stored for longer period

of time


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2.15 Oil Stains

Oil stains is the serious problem that affect the quality of fabric. One possible

reason is the use of excess oil than the actual requirement of the machine. This

excess oil spreads on the machine causing high accumulation of fluff at cylinder,

this fluff than goes under the needles and sinkers which creates oil stains in the

fabric. To control this problem, an appropriate amount of oil should be used.

Another possible reason is the frequent machine stoppages. When machine stops

frequently, the absorption of oil becomes high at the needles and sinker as

compared to the running condition of machine and that causes oil stains in the

fabric.

2.16 Spot Marks on Fabric Surface

Spot marks (Lycra, Polyester, Inlay yarn) on fabric surface are due to improper

adjustment of sinker timing. Proper setting of sinker timing with adjusting feeder

setting controls this problem. Yarn tension is also another reason and it should be

checked by tension meter and adjusted one by one on all feeders and if required

tuck tension should be increased.

2.17 Double Stitch Problem

The following are the precautions to avoid the double stitch problem in a particular

fabric:

Yarn passage must be smooth. Missing eye guides or improper yarn passage

causes yarn to vibrate

Control of yarn Tension. Tension meter should be used to control


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2.18 Air Circulation System

The overall cleaning condition on production floor affects fabric quality. To get

good quality fabric, floor cleaning and fluff suction system should be adequate. To

improve fluff suction system, increase the capacity of suction system or install air

conditioning system to maintain relative humidity of department as well as proper

suction of fluff. At least industrial vacuum cleaner should be used for fluff control.

2.19 Separating & Covering the Knitting Machine

The striper machines should be covered with polypropylene sheets to avoid fluff

accumulation from one machine to another. This will improve the fabric quality.

Similarly, the machines which are not in operation should be covered with

polypropylene sheets from top to bottom for avoiding the accumulation of fluff on it.

Due to less accumulation of fluff on the machine, the maintenance of machine will

be decreased and it will increase the machine life.

2.20 Method of Checking Greige Fabric GSM

It is general industry practice to check the greige GSM with GSM cutter. As in this

case, sample size taken is too small, therefore, GSM measured with GSM cutter

shows more variation. Large dia GSM cutter may be used to make the result more

accurate and reliable. The simple and accurate method to find the actual GSM of

fabric is based on three basic parameters i.e. fabric weight, length and width of the

fabric. It can be checked by producing the fabric / 20 round and then dividing the

weight of produced fabric by the area (length*width) of the fabric as in the section

1.1.

The actual GSM can be calculated as follows:

GSM = (6) / (2) gram / meter 2

GSM = g / m2


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2.20.1 Guidelines for Checking of GSM

The following are the further guidelines for checking the greige GSM:

Actual GSM of greige fabric (as explained above) should be measured at the

start of new article

Greige fabric roll should be cut as per counter meter reading on the

machine. In this practice, weight of each roll will be same. This is the

easiest way to check the GSM of each roll

2.21 Stitch Length of Fabric Sample

Stitch Length should be checked whenever starting the new order or problem arises.

The use of round meter for setting the stitch length is better. However, if it is not

available then, it may be checked manually. But in any case, it must be checked

when starting the new article or in case of any problem.

2.22 Calibration of Round Meter

Round meter is sometimes used for the setting of stitch length. It is advised that

round meter must be checked and calibrated for the correct setting. Check the stitch

length manually and compare the results with the round meter reading.

2.23 Measuring Actual Stitch Length

To find the actual stitch length, take a sample of fabric and mark 100 needles and

then take out at least three yarns each and measure the stitch length. Compare this

value with the round meter value.

Example:

We have a sample of fleece fabric produced on m/c having dia of 30 inch, Gauge 18

and total number of needles 1692. 100 needles were marked and then three knits,

tuck and inlay yarn each were taken out. Stitch length of knit, tuck and inlay was

measured. Mean value of the actual stitch length of knit, tuck and inlay was:


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Knit = 47 cm

Tuck = 41.3 cm

Inlay = 18.9 cm

The round meter reading on the same machine having Machine dia of 30 inch,

Gauge 18 and total number of needles 1692 was found to be:

Knit = 782

Tuck =683

Inlay =300

Converting round meter value to the /100 needle stitch length

Knit = 782/1692*100= 46.2 cm

Tuck =683/1692*100= 40.4 cm

Inlay = 300/1692*100=17.7 cm

Comparison

Comparing round meter reading with the actual readings revealed that:

Actual Knit stitch length is 1.7 % higher

Actual Tuck stitch length is 2.2 % higher

Actual Inlay stitch length is 3.8 % higher

Conclusion

The round meter should be checked at regular intervals to avoid any problem.

However, when variation in GSM arises check actual stitch length as well.

2.24 Fabric Inspection

It is worth considering a total inspection environment which can improve the

overall standard of the inspection department. The main action of a fabric

inspection machine is to unroll measure and re-roll the fabric, and to contribute to

an environment in which it can be inspected by an examiner.


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This requires the following characteristics:-

Suitable edge control to provide a finished roll of attractive appearance

Winding characteristics, which do not distort the fabric structure or

dimensions, which suggests tensionless wind up through, overfeed in the

case of stretch fabrics

Stopping and starting which will not disturb the roll, nor the fabric structure

nor its dimensions

Winding characteristics should be such that any form of handling by the

examiner is minimized

The machine should be simple to load and unload

Lighting should be controllable and of variable intensity, so that the most

critical faults may be detected most easily without loss of detection of less

critical faults

2.25 Analysis of Inspection Sheet Machine Wise

The analysis of defects should be done machine wise. This analysis will show the

individual record of every machine and the traceability of machine with too many

faults will become easier to find the root cause of problems. The collected data

should be analyzed and checked regularly, especially in case of same fabric

construction running on different machines for controlling the variation of faults.

Immediate actions should be taken after observing data for reducing rejection %

age. (Sheet is attached in the annexure-V).


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2.26 Yarn Inspection

Apart from checking the weight of yarn deliveries, following yarn properties may

be checked to ensure the quality of raw material:

Further Yarn Checks (1st order priority)

Count Tests on Staple Fiber Yarns: Check on count variability, within cones

and between deliveries: to be within tolerance of specification

Condition Checks: Check on incorrect condition

Yarn Unevenness (U %)

Further Yarn Checks (2nd order priority)

Yarn twist: On new deliveries and on demand for fault diagnosis. To be

within specified tolerance

Co-efficient of friction: Test and compare to specification

2.27 Use of Compact Yarn

Use of Compact spun yarn in knitting gives following advantages:

Less fly on the knitting machine

Knitting faults and interruptions are reduced and hence higher machine

efficiency

Smoother surface of Fabric as compare to Fabric made from conventional

ring spun yarn

More luster in fabric

Reduced pilling in the fabric


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2.28 Fabric Stability and Finished Width

Fabrics knitted on circular machines have a set number of wales, determined by the

knitting machine used, - its diameter and gauge (needles per unit length of cylinder

circumference). The fabric will be knitted from a certain yarn type and knitted loop

length, partly on economic grounds and partly to avoid being too dense or too light

a fabric.

There is a commercial incentive to finish fabric as wide and as long as possible. The

loop structure of knitted fabrics makes it possible to stretch these fabrics to an

appreciable extent. However, in the stretched state the forces on each loop are not

balanced, and so the fabric becomes unstable, giving it a tendency to revert to a

more natural, relaxed state during which an increase in fabric stitch density will

take place, together with a consequent reduction on area, i.e. shrinkage will always

occur. It is not possible to set a fabric at what are in effect unrealistic dimensions

and at the same time achieves a stable fabric. Therefore, certain diameters of

knitting machines are to be used (which is a must unless we are prepared

continually to replace existing machinery). Since the fabric will be knitted within

fairly narrow ranges of yarn type, count and loop length, then the fabric must be

finished as near as practical to its natural width and length and not over stretched, if

it is to be without excessive shrinkage in service (e.g. washing). In this state the

fabric will have fairly definite width and length dependent on the machine, yarn and

loop length used. Efficient lays should be planned on these dimensions, and not on

some predetermined ideal.

If shrinkage is not an important consideration, then extra width and length can be

considered. The fabric characteristics can be determined by calculations form the

fabric geometry and by trials, and the finished dimensions to be stipulated modified

accordingly. Unless these factors are fully understood, a satisfactory fabric

specification will not be possible.


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3 Machine Maintenance

3.1 Machine Maintenance Schedule

Maintenance of knitting machine is very important that affect the machine

efficiency, machine life and fabric quality. The management should prepare a

maintenance schedule and it should be followed strictly. The main parts of the

knitting machine should be checked with extreme care and responsibility. If the

knitting machine is too old, then maintenance became more important to avoid any

major breakdown. The following are the guidelines for machine maintenance

(Daily, Weekly, Monthly, Bi- Annually and Annually). Also maintenance schedule

is attached in the annexure-VI.

3.1.1 Daily Maintenance

The check points for daily maintenance are as follows:

Yarn feeding device and related parts:

Check yarn feeding device (MPF,IRO), Slipped-off, Loose or broken MPF

drive belt

Malfunction of clutch, IRO tape flipper, etc

Check MPF teeth

Clean fluff from MPF area

Remove fluff from tension washers

QAP (Quality Pulley): diameter, loose lock nut

Lubricators:

Oil level of mist lubricator

Check oil drop rate (should be 100-120 drops/ min)

Supply amount of compressed air

Check lubrication points for disconnection, leakage etc.

Check compressed air pressure


- 21 -

Abnormal Noise:

Knitting elements (cam holders, sinker cap and dial cap)

Yarn feeding units and related parts (QAP, change gear box, drive tape, etc)

Frame (machine bed, take-up unit, motor drive, etc.)

Oil leakage:

Lubricator main body

Part underneath the bed

Oil amount in the oil sump bottle

Connection between oil mist pipes and nozzles

Part underneath the gear ring

3.1.2 Weekly Maintenance

The check points for weekly maintenance are mentioned here under:

Piping for lubrication oil and compressed air

Oil amount in the bed & gear box and make up if required

Check oil sump mist lubricator

Draining of water from the air compressor

Clean the lint fan

3.1.3 Monthly Maintenance

The check points for monthly maintenance are as follows:

Lint accumulation (Check for lint and clean.):

Lint in the control panel

Lint around lint fans and other areas

Lint in the motor cover


- 22 -

Belt tension:

Check main drive motor belt tension

Check drive belt tension for yarn feeding device

3.1.4 Bi-Annual Maintenance

The check points for bi annual maintenance are mentioned here under:

Change the oil in gear box

Change the oil in needle bed

Remove the MPF pulleys and clean with kerosene oil

Machine cleaning should be checked very carefully for all parts

3.1.5 Annual Maintenance

The check points for annual maintenance are mentioned here under:

Change grease in fabric roll winder

Change grease in gear box of yarn feeding system

3.1.6 Machine Overhauling

Each knitting machine should be overhauled once a month. It is a guide line for

overhauling which is followed worldwide.

3.2 Lubrication

Shell Vexilla G or Mobil Vilocite CX 22 or Vickers CL22 or oil of same specs by

any other manufacturer is recommended as knitting oil for needles, sinkers and

cams. The selection of oil should be done keeping in view both the quality of the

fabric and the machine lubrication requirement. In fact it is a compromise between

machine safety and fabric safety. Very good washable knitting oil may not have

good lubrication property and vice versa.


- 23 -

For machine bed, the Sell Tonna Oil S68 (viscosity @40c°55 to 70 CST) or

corresponding oil from any other manufacturer (format for selection of oil,

lubrication procedures and locations is attached in the annexure-VII).

3.3 Sinker Timing Gauge

Sinker timing reference points should be available on all machines for correct

setting of sinker timing gauges.

3.4 RPM Meters and Counter Meters

RPM meters and Counter meters on knitting machines should always be in working

conditions. The advantage of using these meters is the ease in daily production

calculations and minimum roll weight variation.

3.5 Machine Cleaning

The following are the guidelines for machine cleaning:

Each operator should individually take care of the proper machine cleaning

At each doff machine should be cleaned including the net cover

Waste cloth should be used for bed and underside cleaning

Machine cleaning with air pressure should be done only by operator

Cleaning of the creel should also be done

Those machines which are not in production should be covered to avoid

accumulation of fluff on the machine

Operator must be trained to follow the above guidelines and it should be made a

custom.


- 24 -

3.6 Needle Life

The needle life depends upon various factors i.e. the quality of yarn being used and

the design of knitted fabric. The marks on needle buts are due to the uneven surface

of cams. Uneven surface cams should be buffed or new cams should be used to save

the life of needles.

After changing the complete set of needles with the new one, better condition

needles should be sorted out from old set of needles and should be used as

replacement whenever, needle brakes on any machine.

It is very difficult to determine an ideal needle life even for particular design and

machine. It differs with the yarn quality and machine condition. Polyester yarn

generally damages the needles more than cotton. Similarly it also depends upon the

GSM of the fabric to be produced. Keeping the all said factors in mind, the needles

should be used until at least 30000 to 50000 Kgs fabric is produced.

3.7 Needle Break Data

The record of broken needles and individual needles replaced on daily basis should

be prepared. Needle and sinker change schedule should also be maintained

properly. The concerned in-charge must ensure that all the data being collected

should be accurate.

3.8 Operator Responsibilities

Some basic responsibilities of knitting operators to ensure good quality and

production are as follows:

To minimize the faults on the same setting

The yarn path must be as start as possible and hindrance free

The yarn wrapping on the MPF (Main Pully Feeder) should be even

Feeders setting must be OK

Even smaller fault should not be ignored


- 25 -

Daily machine maintenance checking

Fluff should not go inside the machine

Each operator must be allocated with space around its machine(s) and it

must be his responsibility to make sure the cleanliness of that area

Minimum stoppage of the machine

The healthy production should also come with quality

If operator sees any fault he must inform the concerned person

Operator should not start work in case of any noise in the machine

3.9 Analysis of Machine Stoppages

It is better to record the machine stoppages. This data then should be analyzed for

improvement in production. Use problem solving techniques explained in sections

to follow to analyze the data.


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4 Cost Control

4.1 Yarn Waste

It is observed that many baby cones (Pochey) are left over after the completion of

fabric. The yarn from one truck is not being mix used with yarn of other truck

(even yarn of same lot). The mills management normally does not mix the different

trucks of yarn in order to avoid the yarn variation. But this is the wastage of money.

The yarn from truck to truck can be used by confirmation of the same lot from

spinning mills. The yarn that is left over after the knitting of fabric (in the form of

Pochey) is not being analyzed from productive point of view. This yarn waste

(Pochey) should not be more than 10 kilograms/lot. If this waste will increase more

than 10 kilograms/lot then it should be analyzed that how to control this loss.

For example, there is requirement of five trucks of yarn against any order. The mills

management are performing yarn test sample five times to avoid yarn variation.

Each yarn test sample is not more then 5 kgs and after completion of fabric, the left

over yarn in the form of Pochey is 20 kgs of each truck. It means yarn used 25 kgs

for yarn test samples and 100 kgs for wastage (in the form of Pochey). This is totally

wastage of yarn. If the management confirms the yarn lot number then it will save

the 100 kgs of yarn which is being used in unnecessary areas. After the confirmation

of yarn lot, the yarn sample should be tested only one time. It means that in routine

practice, the extra yarn is being wasted four times. In the same way the yarn that is

left over after the knitting of fabric (in the form of Pochey) is too much.

4.2 Oil Leakage

The problem of oil leakage is due to the absence of oil seals and oil nozzles on

machines. If this problem continues, then this is not beneficial from cost point of

view as more consumption of oil. Also it affects the needle life and accumulates

fluff on the machine.


- 27 -

4.3 One Operator for at least Two Machines

In routine practice, one operator handles only one machine. In this case the operator

has too much idle time. One operator should be used to handle at least two

machines because the machines are very close to each other in the knitting floor.

Therefore, the operators can easily handle two machines at a same time.

4.4 GSM Measurement

Normally in industry, GSM of greige fabric is being measured with GSM cutter;

this will produce holes in the fabric surface and also increase waste percentage.

GSM of greige fabric should be measured one time in the start of new article by 20

round method. If there are some doubts in GSM, then it is better to check fabric

stitch length. There is no need to check GSM of each roll. In this practice waste

percentage would be minimized. Any further adjustments in GSM should be made

on stitch length base rather than using GSM cutter.

4.5 Individual Work Order Closing Report

The analysis of rejection percentage should be performed by work order closing

report. This analysis will show the individual record of every work order. It makes

easier to trace out the root cause of rejection. The manager should be checked the

work order report regularly.


- 28 -

5 Fabric Development

5.1 Stitch Length of Fabric Sample

The following is the method of checking stitch length manually:

Take a small piece of fabric (40-50 cm in length)

Mark length of hundred wales on both sides of fabric

Take out ten threads and find out the average length of the threads. This will

be the stitch length of that sample

Note: If fabric sample size is too small, then mark length of thirty wales on both

sides of fabric. Take out three threads and find out the average length of these

threads.

5.2 Determination of Count/ Denier of Given Yarn

The method to find out the Denier / Count value of the yarns in a fabric sample is as

follows:

Put two cut marks at certain distance (30-40 cm) on the fabric sample

Take out different yarns (Count / type) by undoing the knitted structure

Take out at least 10 yarns for each count or type of yarn

Measure the length of each count or type of yarn and add them to get the

total length of yarn (in m) for each count

Now determine the weight of the yarns count wise

Calculate the denier value using the formula:

Denier value = Weight of the yarn in gram x 9000Length of yarn in meters

For determining the corresponding count value, the denier value can be

converted to Count using the following conversion formula:

Count= 5315 / Denier


- 29 -

Example:

Suppose undoing of the knitted fabric provided the following observations:

Type of yarn = 2 (i.e. 2 cotton yarn & 1 Lycra)

No of yarn taken out for each type of yarn= 30

Length of each yarn = 71.23 cm

Total length of Cotton yarn = 30 x 71.23 cm = 2136.9 cm= 21.369 m

Weight of Cotton yarn using weighing balance with a least count of 0.001 g = 0.31g

Thus Denier value of the Cotton yarn will be:

Denier value = Weight of the yarn in gram x 9000

Length of yarn in meters

Denier value = 0.31 x 9000 = 130.56 denier (approximately)

21.369

Converting it into count,

Count = 5315 / Denier

= 5315 / 130.56

= 40.7 Count

= 40/s (approx.)

5.3 Actual consumption of yarn

In planning a certain order, knowing the consumption of yarn is important so that,

required quantity of yarn can be purchased. It becomes more important when we are

using different yarn in the same fabric.

If we have the three end fleece with one type of yarn in Knit and Tuck, and another

yarn the in Loop. To calculate the actual yarn consumption or yarn mixing ratio

following is the procedure to be followed:

Take the a small piece of fabric

Find out the weight of sample fabric


- 30 -

then take out the loop yarn from sample fabric and find out the weight of

Loop yarn

The subtraction of loop yarn weight from sample fabric will give the weight

of knit & tuck yarn

Now the consumption of yarn or mixing ratio can be calculated

EXAMPLE:

There are two methods of calculating Consumption of Yarn in 3 End Fleece.

Suppose we have the three end fleece fabric with 30/s of yarn in Knit and Tuck and

16/s yarn the in Loop.

1st method: When Stitch length of knit and tuck are same and loop is deferent:

KNIT TUCK LOOP

Cotton Cotton Cotton

Count 30 30 16

Stitch length 22 cm 20.5 cm 7.5 cm

Knit and Tuck the count is same, so added Knit and Tuck

= 22 + 20.5

= 42.5 cm = 7.5 cm

= 42.5 × 1 / 30 = 7.5 × 1 / 16

A = 1.417 B = 0.469

Total= A + B = 1.417 + 0.469

=1.886

% of 30/s % of 16/s

= 1.417 / 1.886 × 100 = 0.469 / 1.886 × 100

30/ Ѕ = 75.1% 16 /Ѕ = 24.9%


- 31 -

For 50,000 Kg fabric quantity of yarn required (including 2 % knitting loss)

A= 30/s = 50000 × 1.02 × 0.751 = 38301 kg

B = 16/s=50000 × 1.02 × 0.249 = 12699 kg

2nd method: When Stitch length of knit, tuck and loop are deferent:

KNIT TUCK LOOP

Cotton Polyester Cotton

Count 30 / Ѕ 45 d 16 / Ѕ

Stitch length 22 cm 20.5 cm 7.5 cm

To convert count into denier using formula

D = 5315 / S

5315 / 30 45d 5315 / 16

177.2 d 45 d 332.2 d

Multiplying to stitch length

177.2 × 22 45×20.5 332.2 × 7.5

3898.4 + 922.5 + 2491.5

Total = 7312.4

3898.4 / 7312.4 922.5/ 7312.4 2491.5 / 7312.4

0.533 × 100 0.126 × 100 0.341×100

53. 3 % 12.6% 34.1%

Consumption of yarn

A = Cotton (30 s) 53.3%

B = Polyester (45 d) 12.6%

C = Cotton (16 s) 34.1%


- 32 -

For 50,000 Kg fabric quantity of yarn required (including 2 % knitting loss)

A = 50000 × 1.02 × 0.533 = 27183 kg

B = 50000 × 1.02 × 0.126 = 6426 kg

C = 50000 × 1.02 × 0.341 = 17391 kg

5.4 Ratio of Cotton to Lycra Feed

It is common practice in the industry that Lycra percentage is always set on the

machine by hit and trial method which is not an efficient way. Setting the exact

percentage of Lycra is difficult in this way. If we have to set the 3 percent of Lycra

than, by hit and trail it is possible that, this value may be set to somewhat higher. In

case of a large order a small increase in this percentage will increase the cost of

production as Lycra is very costly. In order to set the Lycra percentage in more

efficient way the following method is very useful.

5.4.1 Finding the Percentage of Lycra

If we have a sample of Lycra knitted fabric and wants to produce that fabric with

same percentage of Lycra. For this purpose we have to calculate the ratio of the

feed speed of cotton and Lycra to determine how slower the Lycra must be fed as

compared to cotton yarn so that we get same percentage of Lycra in the fabric. The

following is the procedure:

Put two cut marks at certain distance (30-40 cm) on the fabric sample

Take out different yarns (count / type) by undoing the knitted structure

Take out at least 10 yarns for each count or type of yarn

Measure the length of each count or type of yarn and add them to get the

total length of yarn in meters for each count

Now determine the weight of the yarns count wise

From weight find out the Lycra percentage


- 33 -

Calculate the denier value of cotton yarn using the formula:

Denier value = Weight of Cotton yarn (g) × 9000 Length of Cotton yarn (m)

Now find out the Denier value of Lycra by using following formula:

Denier of Lycra = Weight of Lycra × Cotton Denier Weight of Cotton

Find the Lycra Feed ratio using following formula:

Lycra Feed Ratio = Calculated Denier Actual Denier to be used

Example:

Suppose we have a Lycra based Fabric sample. Un-roving of the knitted fabric

provided the following observations:

Type of yarn = 2

Feed of yarn = 2 cotton yarn & 1 Lycra

No of yarn taken out for each type of yarn= 15

Length of each yarn = 110.4 cm

Total length of Cotton yarn = 110.4 x 15x 2= 3312 cm = 33.12 m

Weight of 30 Cotton yarns = 0.66 gm

Weight of Lycra = 0.02 gm

Cotton Yarn Denier = 9000*0.66/33.12= 179.35

Cotton Count = 5315/179.35 =29.6 30/s

Lycra Denier = 9000*0.02/ (15*1.104) =10.87

If we have to use 40 D Lycra than, the ratio of feed speed should be

Lycra Feed Ratio = 40/10.87 = 3.68

i.e. Lycra should be fed at 3.68 times slower in speed than cotton. If we adjust the

Lycra feed according to this calculated value then we will get the same percentage

of Lycra in the fabric.


- 34 -

Consumption of Yarn

% age of Cotton = Cotton Weight / (Lycra Weight + Cotton Weight)

= 0.66 / 0.68 ×100

= 97.06 %

Lycra % = Lycra Weight / (Lycra Weight + Cotton Weight)

= 0.02/0.068*100

= 2.94 %

5.5 Determination of Finish Fabric Gauge

Sometimes, we may receive the finish fabric from the customer to knit. In that case,

the following is the method of finding the gauge of the machine used to produce

that fabric:

In case of full width finish fabric

If we have full width finish fabric then:

Find the total width of fabric

Count 100 wales and measure the corresponding length and find the wales /

length

Calculate the number of needles using following formula:

Total no. of Needles / Total Width of Fabric in cm = Wales/ cm

Find the Dia of the machine keeping in view the following guidelines:

Note: This table is based on the experience. So, it is for reference only to start with.

Total Width of Fabric

(cm)

Dia of the Machine

(inch)

120 24

130 26

140 28

150 30

165 32


- 35 -

Calculate the gauge of the machine used to produce that fabric by using

following formula:

Gauge = Total No. of Needles / (п × Dia of the machine)

Example:

Measured Width of the fabric = 75.5 cm

Total Width of the fabric = 75.5 × 2 =151 cm

Length of 100 wales = 8 cm

Suppose X is the total number of needles.

Therefore,

X/151 = 100/8

X = 1887.5

Referring to the above table the dia of the machine comes out to be 30 inch.

Now,

Gauge = 1887.5 / (3.143 × 30)

Gauge = 20

In Case of Swatch of Finish Fabric

Sometimes, we do not have full width finish fabric instead; we receive a swatch of

finish fabric from the buyer. In that case to find the gauge the following method

should be followed:

Assume the total width of the fabric or if factory is producing the fabric for

its garment division then, get the width of the fabric from cutting

department who will provide the same on the basis of the garment to be

made from that fabric

Count 100 wales and measure the corresponding length or if swatch is too

small count Wales / inch


- 36 -

Calculate the total number of needles using following formula:

Total No. of Needles / Total Width of Fabric in cm = Wales / cm

OR

Total No. of Needles / Total Width of Fabric in inches = Wales/ inch

Find the dia of the machine keeping in the view the above table

Calculate the gauge of the machine by using following formula:

Gauge = Total No. of Needles / (п × Dia of the machine)

5.6 Setting of GSM in Greige Fabric

There is no formula for setting GSM of greige fabric with respect to finished fabric.

However, as a starting point GSM in greige fabric may be adjusted at

approximately 55 to 60 digits less than the GSM of finish fabric. But it requires

experimentation to get the final result.

5.7 Knitting process

The following are the steps to follow for analyzing a particular knit sample and to

reproduce it:

5.7.1 Analyze the Sample

The following are the steps to analyze a particular knitted fabric sample to be

produce:

identify types of yarns in sample

count courses and wales per cm in each structure

determine stitch length and counts of yarns used by unroving

estimate likely gauge of machine on which sample knitted

determine the design, pattern repeat

check GSM


- 37 -

5.7.2 Development of Knitting Specification

select nearest suitable commercial yarn available and gauge of machine to

be used for adaptation to reproduce sample

knit swatch for each structure at calculated course length based on

experience of machine settings

check course length by un-roving or marked yarn method

adjust until correct (tolerance of +- 2% suggested)

record settings (on knitting condition data chart explained earlier) e.g. input

tension, weight of take down, knock over depth

knit sample panels

check and record complete panels for appearance, dimensions and weight

on the basis on data recorded set up other machines similarly

check for course length and adjust necessary

N.B. if (c) has been correctly carried out machine adjustment should not be

required.

5.8 Knitting Construction and Layout Graph

The knitting construction and layout graph sheets for single knit, rib and interlock

are attached in the annexure-VIII. This will help to understand the construction of

fabric. Graphs should be made and maintained for each type of fabric as a future

reference.

5.9 Use of 1/1000 Gm Graduation Scale

It is better to have the weighing scale of 1/1000 gm least count. It is very useful

whenever finding count of yarn, % of any particular yarn in the fabric or GSM of

fabric. In these cases, a great accuracy of weight is required for correct results.


- 38 -

5.10 Knitting of 100 % Polyester or 100 % Lycra

When 100 % Polyester yarn or 100 % Lycra yarn is used for knitting fabric then it

is necessary to arrange a new set of needles on knitting machine. It is impossible to

knit fabric with existing settings and needles of knitting machine. Otherwise, needle

line appears in fabric. First of all a small sample of fabric should be prepared and

after processing its conditions should be checked carefully. If there is some severe

needle marks in fabric then immediate action should be taken for removing needle

marks. In case of 100 % Polyester knitting, management should be more conscious

about yarn tension. Otherwise, when Polyester yarn is broken; it is very difficult to

watch with naked eye during knitting or in running condition.

The coordination between knitting and dyeing department is very essential for

producing this type of fabric. The management should first try to produce Polyester

Cotton blend fabric. After getting successful results in knitted blend fabric,

management should try for knitting of 100 % Polyester or 100 % Lycra fabric.


- 39 -

6 Useful Calculations

6.1 Calculating GSM of Swatch

The method to calculate the GSM of swatch using following formula:

GSM = Weight

100×100 Width × Length

For example:

3cm

5cm

Width = 3(cm)

Length = 5(cm)

Weight = 0.37g

GSM = 0.37

100×100 3 × 5

GSM = 0.0246 × 10000

GSM = 246.7

0.37g


- 40 -

6.2 Calculating Length from Fabric Weight

Calculation formula for converting Kilograms of fabric to Meters is as follows:

Since,

GSM = Weight (g)

Length (m) × Width (m)

Therefore,

Length (in meter) = Weight (g)

GSM × Width (m)

6.3 Conversion Formulas for Cotton Count and Polyester Denier

S = 5315 / D

OR

D = 5315 / S

Where,

S = English Count

D= Denier


- 41 -

6.4 Formula for Finding Gauge of the Yarn Count

If,

S = Cotton Count

G = Gauge

C = Metric Count

Then,

G= K √ C

OR

G² = C÷ K²

Since, C = S × 1.6936

G² = (Sx1.6936 ÷ K²)

G²= S × (1.6936 × K²)

Where K= Constant

For Single Needle K= 3.5

For Double Needles K = 2.5

Example:

For S = 20 s K = 3.5

Using above relation

G = 20.36 → 20 G


- 42 -

6.5 Calculations for Finding GSM

The following is the method for finding the GSM with respect to stitch length.

When we know the value of Stitch Length, Dia, Gauge, Finish Width and Yarn

Count then, we can find the GSM.

If,

Dia in Inches = D

Gauge = G

Count = S

Number of Needles = D × 3.14 × G

Fabric Width in Inches = F

= F × 2.54

Wale = D ×3.14 × G

F × 0.0254

= 123.6 × G × D

F

Course = D ×3.14 × G × 5

F × 0.0254 4

= D × G × 154.53

F

One Loop Length L (m) = Stitch Length

No. of Wales

Yarn Length = Wale × Course × L


- 43 -

= 123.6 × G × D ×D × G × 154.53 × L

F × F

= 19099.9 × G² × D² × L

F²

W (GSM) = 5315 × 19099.9 × G² × D²×L

S F²× 9000

= 11279.6 × G² × D²×L

F²× S

For Example

Dia = 30

Gauge = 20

Count = 22

Number of Needles = 30 × 3.14 × 20 = 1884 ↔ 1860

Fabric Width = 62" = 62 × 2.54 = 157.48 cm = 1.5748 m

Wale = 1860 ÷ 1.5748 m = 1181

Course = 1181 × 5 = 1476

4One Loop Length = 61.5 cm = 0.003075 m

200 (wale)

Yarn Length = 1181 × 1476 × 0.003075 = 5360.2 m

D = 9000 × W L

W = D × L 9000

= 5315 × 5360.2 9000 × 22

W (GSM) = 143.9 g / m²


- 44 -

7 5 S (A Japanese Management Technique)

5S is a Japanese quality management concept that was introduced and advised to

practice in the factories for creating a high quality, a highly productive and a safe

working environment. 5S is a simple and systematic five step Japanese approach for

clean, neat, properly organized workplace through employee’s initiatives. It should

be gradually adopted and than it will become the habit. It is an acronym for five

Japanese words Seiri, Seiton, Seiso, Seiketsu, and Shitsuke.

The meaning of 5S is explained as follows:

Seiri: To sort and throw away unnecessary items

Seiton: A place for everything and every thing in its place

Seiso: Maintain high standards of Cleanliness

Seiketsu: Standardize all procedures

Shitsuke: Train and maintain Discipline

5S can provide a solid foundation for other productivity and quality programs such

as Total Quality Management, Total Productive Maintenance, Waste Reduction and

Just in Time Production and Inventory Management. 5S reduces the gap between

the top and bottom levels of employees and develop a team work.


- 45 -

7.1 How to Practice 5S

7.1.1 Seiri

Identify the things which are not of use anymore. Examples are defective

equipments, outdated material and obsolete documents etc. The following guide can

be used to classify all the necessary items.

Guide to Classify Unnecessary Items

The company should have a set of objective criteria on the retention and disposal of

items.

Unnecessary Items

Items of some Value

Items of no Value

Items required special disposal

Sorting

Throw away Immediately

Relocate or Sell

Look for an in-expensive safe way for disposal

Action Require


- 46 -

7.1.2 Seiton

It is important to prepare a plan for the location of the objects. The plan will make it

easier to locate items when they are needed. It is important to return the items to

their original place after use. The following guide can be used to help in arranging

the necessary items.

Guide to classify Necessary Items

It is likely to forget the location of certain objects not often used. To prevent this,

“Visual Control” can be used to mark out the items and their locations. With

properly marked storage places, out of place items can be easily spotted. The use of

colors, labels, charts can be used for visual control.

Necessary Items Items used

Occasionally

Items used Constantly

Items not used frequently but still in-need

Sorting

Must be placed nearby

Can be placed further away

Must be stored separately in a designated place

Action Require


- 47 -

7.1.3 Seiso

The practice of Seiso is important for the company’s image and health of its

employees. It is also prerequisite for the production of quality goods and services.

Following are the some ways to implement Seiso at the workplace:

Organize a big cleaning day once or twice a year that involves everyone

Set aside some time each day to clean workplace. Cleaning work is easier

and faster when done daily as the dirt accumulated would be minimal

Employees to be made responsible for the cleanliness of their own

immediate work areas

Conduct regular cleaning of machines and tools that are in use. This would

be a good starting point for productive maintenance because clean

machinery and equipment encounter fewer breakdowns

7.1.4 Seiketsu

To maintain a high standard of workplace by keeping everything clean and orderly

at all times the 5S movement must be sustained within the company by repeating

Seiri, Seiton and Seiso activities. The 5S must be implemented according to a

company wide standard. The purpose is to make sure that the entire organization

follows the same rules; same names and colors etc.

Following are some guidelines for Seiketsu (Standardization):

Create a cleaning system for house keeping. For example, make a weekly

schedule for cleaning and organizing the workplace

Form 5S teams among the various departments to brainstorm on possible

housekeeping projects. These will help in creating a sense of ownership and

participation among the employees. The achievements by these teams

should be exhibits to both management and colleagues to share their

experiences


- 48 -

Organize inter-departmental competitions on housekeeping. These will

bring motivation and create the importance of housekeeping at the

workplace. Also it will help to create new ideas on visual control to be

implemented resulting higher productivity

7.1.5 Shitsuke

The 5S program is a long term approach to improve the work environment. The

benefits could only be fully realized through the continued efforts of every

employee in the organization. Total participation is must for Shitsuke to succeed.

The organization should train all the employees and develop a company culture

whereby good housekeeping becomes a habit for everyone.

Following are some ways to implement it:

Every one should play an effective role in housekeeping efforts at the

workplace to set good examples for others to follow

Plan a comprehensive training on 5S and implement it

With continuous improvement in mind the changes brought at workplace to

convince employees and create positive attitude towards 5S

Create a 5S culture where everyone willingly participates and give rewards

on good practices


- 49 -

8 Fish Bone Theory

The Fish Bone Theory is a simple and systematic Japanese approach for solving the

problems. It should be gradually adopted than it will become the organizational

habit. After analysis of the data, this theory must be used for solving different types

of problems. Fish Bone Diagrams help you to think through causes of a problem

thoroughly. Its major benefit is that it push you to consider all possible causes of the

problem, rather than just the ones that are most obvious. The approach combines

brainstorming with use of a type of Concept Map.

Follow these steps to solve a problem with a Fish Bone Diagram:

8.1 Identify the Problem

Write down the exact problem you face in detail. Where appropriate identify who is

involved, what the problem is, and when and where it occurs. Write the problem in

a box on the left hand side of a large sheet of paper. Draw a line across the paper

horizontally from the box. This gives you space to develop ideas.

8.2 Work out the major factors involved

Next identify the factors that may contribute to the problem. Draw lines off the

spine for each factor, and label it. These may be the people involved with the

problem, systems, equipment, materials, external forces, etc. Try to draw out as

many factors as possible. If you are trying to solve the problem as part of a group,

then this may be a good time for some brainstorming. Using the 'Fish bone'

analogy, the factors you find can be though of as the bones of the fish.


- 50 -

8.3 Identify Possible Causes

For each of the factors you considered in stage II, brainstorm possible causes of the

problem that may be related to the factor. Show these as smaller lines coming off

the 'bones' of the fish. Where a cause is large or complex, then it may be best to

break it down into sub-causes. Show these as lines coming off each cause line.

8.4 Analysis your diagram

By this stage you should have a diagram showing all the possible causes of your

problem. Depending on the complexity and importance of the problem, you can

now investigate the most likely causes further. This may involve setting up

investigations, carrying out surveys, etc. These will be designed to test whether

your assessments are correct.

The examples of fish bone diagram as applied in knitting are attached in the

annexure-IX.


- 51 -

9 Employee Participation & Training

Organizations should make full use of its employees- its most valuable resource.

Employees actually performing the operations often have the best idea for

improving them. Human resource is as essential an aspect of processes as

technology. The abilities of managers and workers, and how they are organized,

trained and motivated can give a firm a competitive edge. Firms can capitalize on

the insights and experience of their employees in various ways, ranging from

departmental problem-solving teams to cross-functional, self-directed teams.

However, to utilize fully the talents of their work force, firms must establish the

proper environment, which includes restructuring the organization and its

incentives, appropriately designing jobs, and using the proper tools to measure

performance.

9.1 Employee Training

Organization must rely on their employees to anticipate possible problems, develop

new product, increase productivity and quality to remain competitive. In order to

make it possible On-job training is one of the useful tools. Teaching new work

methods to experienced workers or training new employees in current practices

helps to achieve our goal.

Managers too need to develop new skills not only those directly relating to their

own duties but also those needed to teach their sub ordinates.

Systematic training involves the training of a person in: -

Basic knowledge

Correct methods

Quality standards (It means the establishment of the threshold at which level

of severity a defect becomes unacceptable, i.e. a fault.)


- 52 -

Without this last item defective production cannot be prevented. It is vital that all

faults and defects that are likely to arise in any job should be taught to all trainees

during their instruction. An operative must be able to recognize these faults and

take action on them, that is, to report, correct or prevent them and where possible,

to prevent their recurrence.

Training of Quality standards is greatly assisted by a library of faults, each fault

being illustrated in the various degrees of severity, - from certainly acceptable to

definitely no.

Good quality products can only be produced by the operatives, or those who fold

and pack no one else. They cannot produce quality without being fully aware of

what exactly is required. Responsibility for the production of good quality lies with,

and is in the hands of, the person teaching the job, primarily by good

communication, by making the newcomer aware of specifications and tolerances,

faults themselves, their effect and the appropriate action to take.

Such communication or training if properly planned and executed will greatly assist

in minimizing the cost of poor quality. The operatives will know from the start what

is required, and equally important be able to spot trouble before it gets out of hand

and know how to handle it. It will also help to avoid the painful scenes of huge piles

of sub-standard work being returned for rectification, which more often than not are

due to a lamentable lack of positive communication. Only in this way will quality

be controlled, costs remain at an acceptable level and customers be satisfied.


ANNEXURE


Annex-I: Knitting Program Chart

Machine #

Machine Type

Machine Gauge / Dia

Machine RPM

Work Order #

Yarn Count

Yarn Brand

Fabric Type

Slitting Line YES NO

Stitch Length

GSM


Annex-II: Data Chart for Knitting Conditions

1 2 3 4Yarn Count

1 2 3 4Stitch Length

Round Meter

Yarn Tension

Sinker Timing /Needle Timing

Feeders Position

Master Wheel Gear Teeth Master Wheel MPF Tape No.

Greige GSM Finish GSM

Possible Problems that Occurred

Possible Solution must be kept Future

Reference

Date Work Order No.

Machine No. Pattern

Dia Gauge

No. of Feeders RPM


Annex-III: Machine Counter Status


Annex-IV: Production Analysis Graph


Annex-V: Machine Wise Inspection Report


Annex-VI: Machine Maintenance SchedulePeriodical Maintenance Sheet

If any abnormality should be found during operation, please stop the machine immediately and take necessary corrective measures.

Frequency or timing

Items to be inspected

Before Installation

Enough room space for machine installation Electric wiring by qualified electricians Air piping work by qualified techniciansYarn feeding device and related parts: Yarn feeders (MPF, IRO, YS2, etc.):Slipped-off, loose or broken drive belt Positive yarn feeders (MPF**, MFD**, etc.): Malfunction of clutch, IRO tape flipper, etc. Lint accumulation onto yarn feeders including tension cymbals QAP (Quality pulley):diameter, loose lock nut

Lubricators: Oil level in the tank Supply amount of compressed air Lubricating condition for knitting elements (disconnections, leakage, etc.) Compressed air pressure Supply amount of lubrication oil

Abnormal noise: Knitting elements (cam holders, sinker cap and dial cap) Yarn feeding units and related parts (QAP, change gear box, drive tape, etc.) Frame (machine bed, take-up unit, motor drive, etc.)

Daily

Oil leakage: Lubricator main body Part underneath the bed Oil amount in the oil sump bottle Connection between oil mist pipes and nozzles Part underneath the gear ring

Weekly

Piping for lubrication oil and compressed air Oil amount in the bed Oil sump channel(for oil mist sump) Draining of water in the air compressor

Lint accumulation (checks for lint and clean.): Lint in the control panel Lint around lint fans and other areas Lint in the motor coverMonthly

Belt tension: Drive motor belt Drive belts for yarn feeding device

Semi-annual Oil change for the gear box and the bed

Annual Grease change for the take-up unit and the yarn feeding units


Daily Machine Inspection Check Sheet


Weekly Machine Inspection Check Sheet Piping for lubrication oil &

compressed airOil amount in the bed Oil sump channel for oil

mist sumpDraining of water in the air

compressorMONTH

Week1

Week 2

Week 3

Week4

Week1

Week2

Week3

Week4

Week1

Week2

Week3

Week4

Week1

Week2

Week3

week4

JAN

FEB

MAR

APR

MAY

JUN

JULAUG

SEP

OCT

NOV

DEC


Monthly Machine Inspection Check SheetLint accumulation

(check for Lint &Clean)Belt TensionM

ONTH

Lint in the control panel

Lint around lint fans & other areas

Lint in the motor cover

Drive motor belt Drive belts for yarn feeding device

JAN

FEB

MAR

APR

MAY

JUN

JUL

AUG

SEP

OCT

NOV

DEC


Inspection Check Sheet

Semi-Annual Annual

GREASE CHANGEYEAR TAKE-UP

UNITYARN FEEDING

UNITS

OIL CHANGEMONTH GEAR

BOXBED


Annex-VII: Lubrication

NOTE1. Please use the oil described in above the table or same quality, pure and clean oil.

When adding oil, please ensure dust lint etc. does not get in to the machine.

2. If the machine becomes too hot or if there is an unusual noise, stop the machine immediately and check the lubricating conditions.

3. The bed, gear box and stationary bevel gear are each design with an oil bath system.Please exchange oil periodically, as recommended in the table. If any of the oil amount falls to the minimum level. Please immediately add oil.The bed oil gauge will not shown accurate amount of oil during the operation of the machine(There are cases when showing as “0”), so when confirming the amount, stop the machine, and after about 5 minutes, please confirm the oil amount.

Lubrication LocationLubrication Procedures & Number of Time

Oil Used

Bed (Gearing)

Gear Box

After test running of 1 month,Thereafter every 6 months

SHELL: TONNA OIL S68(Please use the oil described in

above or same quality ofViscosity@40˚C 55 to 70)

Take-Up Device(Ratcht Wheel,Super Gear, Stationary Bebel Gear & Bearing)

Manually---- once a yearSHELL : ALVANIA GREASE # 2MOBIL : MOBILUX GREASE #2

Needles, Sinkers & Cams

Continuously by automaticoil mist lubrication

SHELL: VEXILLA GMOBIL: VILOCITE CX 22VICKERS: SPOTLESS C. N. 22 : VICKERLUBE L. C. 22(Specially develop for use with Lycra when heat setting is the first finishing operation.) MILLERS: KAYSTOLGULF : LORTEX 22ESSO : TELURA KLUSER : Text- 22N


Annex- VIII: Knitting Construction Graph


Knitting Construction Graph


Knitting Construction GraphSample No. Single Knit


Annex-IX: Fish Bone ChartFor Productivity Improvement

ConeLoop Length

Speed Fluff

Gauge Shape of ConeKind of Pattern

Crush Dent or HollowCount

Yarn Speed No. of Feeder

Stopper

Centering of Creel Scratch

Tension Mind M PF Tape

Positioning of Tail Knot Education Yarn Carrier O peration

NeedleNeedleBed

Needle Ditch Regular Check

Improvement ofProductivity

Paper Tube

Yarn

ProductionControl

KnittingC ondition

O perator


For Oil Stain Winding

Periodic Upkeep Guide

StorageStandard Action

Needle

Place of LubricationNeedle Bed

TransportLubrication Needle Ditch

Oil Pack Oil Volume

Oil Volume Storage

Place ofCheck Lubrication Knot

Reception

Dyeing Transport Tail Periodic Upkeep

ConeGuide

Production Control

Stain

Yarn

Dyeing Factory

Inspection


For Vertical Line

Friction Declination of Pattern Bend

Difference of Design

High Wearing

Friction FrictionMotionless

Measure Frame Latch

Friction

Rivet BendDamage

Friction Loose Fitting Hook

Roller Friction

Butt

Difference of Pattern Needle ditch & Bed

Vertical Line

Needle

Touch Line


For Dropped Stitch

LatchNeedle

Kind of PatternLoop Length Yarn Speed Gating

Yarn Speed BendTension Levering

Timing Position Creel

Guide

Winding Tension Scratch Space of Guide

Hardness Slipping from Cone Cone

Dent or Hollow Hairiness Tight Snarl

QualityTail

Tail Knot

Knitting Condition

Production Control

Dropped Stitch

YarnPaper Tube


For Needle Break

Loop Length

Kind of Pattern

Cone Yarn Speed

Adjustment

Needle Ditch Cam

Friction Gating Needle Needle

Bed

Needle Latch Regular check

Operation Pressure Weight

Winding Tension

Yarn

Needle Break

Production Control

Knitting Condition

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