Process control of Weaving

Name : MAZADUL HASAN SHESHIRID: 2010000400008Batch: 13th Batch (Session 2009-2013)Department: Wet Processing Technology Email: mazadulhasan@yahoo.comBlog: www. Textilelab.blogspot.com Southeast UniversityDepartment of Textile Engineering

PREPARED BY ©right

Introduction : Process control is defined as a statistical & engineering tools or

discipline that deals with architecture ( structure ) , mechanism and algorithm

(sequence of finite instruction ) for controlling the output of a specific production

process . Quality is formed during production process . So, if a production process

is not controlled, the target production quality or reference parameter may not

achieved

INTRODUCTION

Process control is performed by six steps :

1. Step-1: Draw process flow chart showing real change in products geometry

2. Step-2 : Segregate or highlight the part of the flow chart where any change is taking place

3. Step-3 : Find the set points or control points value at each step

4. Step-4 : Determine which output variables have gone out of the range of standard / reference values beyond tolerance

5. Step- 5 : Identify cause which is responsible

6. Step-6 : Make recommendation as what to do

PROCESS CONTROL

PROCESS FLOW CHART OF WEAVING

Fabric Sample :Denim FabricConstruction :( 73 × 43 / 15 × 10 ) × 55Structure :TwillInterlacing Pattern :2/1Yarn Type :Cotton YarnGSM :230

Process Control of Warping Section

Input Variable of Warping Input Quantity Required QuantityYarn Count 15 16

CV % 10 12Strength / tenacity 11 13

Breaking elongation (%) 8 8.5Minimum Staple length of Yarn 2.5 2.7

Contamination Moderate ModerateYarn type Cotton Cotton

Yarn hairiness Moderate LowYarn micronaire value 3.5 4

Twist factor 4 4.5

Output Variable of Warping

Output Quantity

Required Quantity

Process Control

Yarn uniformity (CV % ) 10 12 Uniformity of warped yarn depends on the uniformity of the input raw yarn. By

controlling the uniformity of raw yarn warped yarn uniformity also can be

controlledBroken or loose ends 10 5 To reduce yarn breakage lower strength /

tenacity yarn has to removeDensity of

package(yarn/inch)132 130 To maintain the yarn density of warp

beam perfect count of V – reed have to be used

Beam barrel diameter ( inch)

12 13 To maintain the warp beam diameter , beam barrel diameter also have to control

during selection of warp beamWidth of warp beam 58 60 To produce the actual wide of the fabric

the warp beam diameter also have to be perfect . It is control during selection of

warp beamCoarse knots 10 5 To reduce coarse knot actual quantity &

type of yarn twist have to be maintain

Process Control of Sizing Section

Output Variable of Sizing

Output Quantity

Required Quantity

Process Control

Count of sized yarn 8 10 To maintain sized yarn count proper amount of sizing percentage have

to be maintainedUniformity of sized yarn Moderate Good Uniformity of sized yarn can be

maintained by properly sizingPercent of size 3 1.5 Percent of size can be maintained

by controlling the immersion rollerStrength & uniformity

of sized yarn13 15 Strength & uniformity of sized yarn

can be maintained by maintaining the proper sizing recipe & heat of

drying chamberUnwindability Low Moderate Unwindability can be reduce by

properly drying sized yarnDensity of sized beam

( yarn / inch )73 75 Density of sized beam can be

maintained by controlling the width of headstock

Broken , missing , crossed sticky ends

5 3 Broken , missing , crossed sticky ends can be reduced by controlling

the yarn tension during sizing

Process Control of Drawing-in & trying Section

Output Variable of Drawing in & trying

Output Quantity

Required Quantity

Process Control

Cross ends 5 3 Cross ends can be reduce by carefully drawing - in

Extra ends 10 5 Extra ends can be reduce by conforming sufficient yarn strength

Process Control of Looming Section

Output Variable of Warping

Output Quantity Required Quantity

Process Control

Construction 73 × 43 / 15 × 10

75 × 45 / 16 × 12

Construction of the fabric can be maintained by using proper reed

count &pattern cardGSM 230 235 GSM of the fabric can be maintained

by using proper fabric construction & yarn count

Salvage Structure Plain Plain Salvage Structure can be maintained by using proper type of selvedge &

the salvage forming pattern cardBroken ends / picks 5 3 Broken ends / picks can be reduce

by controlling the RPM of the loomDouble ends / double picks

5 3 Double ends / double picks can reduce by carefully drawing – in

Output Variable of Warping

Output Quantity Required Quantity

Process Control

End out / miss picks / knot

6 4 End out / miss picks / knot can be reduce by properly adjusting the

ends / picks after brokenHole ( per lot ) 10 8 Holes in the fabrics can be removed

by reducing the no. of naps in the yarn

Reed streak 3 2 Reed streak can be removed by maintaining or replacing the reed

Stop marks ( Per lot ) 8 5 Stop marks can be reduce by reducing the machine stoppage time

during productionDirt amount Moderate Low Dirt amount can be reduce by

controlling the dirt contamination & carefully handling the machine

Conclusion: By this experiment we have learn about process quality control of weaving section. Which has increased our practical knowledge about process quality control. It will be helpful for our future practical knowledge.

CONCLUSION: