Warping

Post on 16-Jul-2015

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Transcript of Warping

Presented by:Md. Nazmul Hassan Rayhan

Department of Textile Engineering

Daffodil International University

Warping:The parallel winding of warp ends from many winding packages (cone or cheese) on to a common

package (warp beam) is called warping.

Types of warping:

1. Beam warping – direct warping.

2. Patterns band or drum warping – Sectioned warping,(Indirect warping)

3. Ball warping

WARPING:

Beam WarpingA weavers beam may have up to 10,000 ends and if this were to be produced directly it

would be necessary to have up to 10,000 creel packages. Such an arrangement would

be very difficult to accommodate and manage ;consequently it is normal practice to

produce wrappers beams which may contain up to about 1000 ends and these are

combined at the slashing stage. Because of the difficulties involved in combining the

ends ,patterned warped beams are seldom produced on the direct system and any

pattern that is produced is achieved by combining beams of various colors at the later

stage of slashing.

This imposes limitations which can only overcome by changing to pattern weaving.

Sectional Warping ProcessIn sectional warping sections are made sequentially and because of this the process is

rather slow ;it is the practice therefore to produce no more than is required to fill a single

weavers beam. The result is that the sectional warping is used mainly for short runs or

for complex color patterns.

TYPES OF WARPING

The essential features of a good warp are as follows:

1. Sufficiently and uniformly strong.

2. Uniform in cross section.

3. Uniform warp tension.

4. Uniformly sized.

5. Less hairy and clean.

6. Minimum no. of knots .

7. Proper or standard size and types of knots.

8. Free from naps, slobs and loose fibers.

9. Parallel arrangement of warp yarn in the weavers beam.

QUALITY OF A GOOD WARP

Importance of warping:

1. Constructions of beam warp yarn.

2. Constructions of a parallel yarn sheet.

3. Modifying the faults of yarn like thick & thin places, large knots

etc.

4. Winding the predetermined length of yarn.

5. Combination of small packages.

6. Finding long length of warp yarn.

7. Accelerating the next process.

IMPORTANCE OF WARPING

Objects of warping:

The object of warping is to convert a predetermined number of single end packages,

such as cones or cheeses into a sheet of yarn of specified length & width. The

individual’s ends in the warp are uniformly spaced across its full width. The warp yarns

comprise one of the systems of yarns required to produce a woven fabric & also for

warp knitting. The objective at warping, as erroneously considered by many is not at all

to remove yarn faults, the breaks due to these being only incidental.

OBJECTS OF WARPING

WARPING ELEMENTS & MOTION

Each warping m/c has the following warping elements & motion:

1. Warping creel for accommodation the bobbin.

2. A builder motion.

3. A guide reed. Uniformly spreading the yarn over the warp width.

4. A measuring motion registering the warping length.

5. An automatic knocking off motion to stop the m/c up on achieving the required length of

warping in case of yarn breakage.

6. A drive

7. A starting & stopping motion.

8. Warping m/c is furnished with package doffers signal devices, blowers. Fluff -exhaust

system.

WARPING PROCESS INVOLVES

Check List Before Production:

With the production before data control operator will call-up the following for

recording:

1. Warp length shift.

2. Down time.

3. Efficiency.

4. No. of thread breaks.

5. No. of warp beam doffed.

6. Time for thread repair.

7. Time for beam change.

8. Operator must check yarn quality in term of count, material, and color

with customer demand.

9. Operator must check yarn quality in term of strength and record yarn

break rate. Standard for good quality yarn 10 breaks/10,00,000 meter.

CHECK LIST BEFORE PRODUCTION

COMPONENTS OF WARPING MACHINE

HEAD STOCK:

1. Guide Reed : Uniformly spread the yarn over the warp width.2. Adjustable V-Reed : Guides the yarn to follow the fixed path.3. Speed Controller : control the speed, crawl speed or full speed.4. Pressure Roller : Exert required pressure to the warp yarn.5. Measuring Device : Measures the length of the yarn.6. Beam Bracket : Holds the warp beam.7. Emergency Stop Device: For emergency stop.8. Automatic Knock Off : Stop m/c at achieving required length of beam

or in case of 9. Yarn breaks.10. Electrical Panel Board : To give the automatic controlled

function.

In this process, the threads are being directlywinding on a beam while unwinding the yarnfrom creel

High speeded warping

HI-SPEED WARPING MACHINE

YARN PATH DIAGRAM OF MACHINE

Main Parts:

1. Yarn cone or Chase

2. Balloon Breaker

3. Yarn tensioner

4. Yarn guide

5. Ceramic guide

6. Auto stopper

7. V-reed

8. Lease rod

9. Roller

10.Pressure Roller

11.Pre-beam

Major components of Warping Machine:

Warping machine has three major components:

1. Creel

2. Head Stock

3. Pressure roller

4. Control Device

Creel: •Parallel creel with travelling package•Creel capacity of SIM fabric direct warping m/c:

oNo. of warping m/c: 2oM/c no 1: Both side: 756

Symmetric diagram OF DIRECT WARPING MACHINE

DIRECT I HI-SPEED WARPING MACHINE

HI-SPEED WARPING MACHINE

Dispo↓

Yarn from store↓

Creeling↓

Warping

Working principle of H.S. Warping

• At the beginning so many beams are prepared as the following equation

Number of beams =𝑡𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑤𝑎𝑟𝑝 𝑦𝑎𝑟𝑛

𝐶𝑟𝑒𝑒𝑙 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦

• In which way threads are assembled shows the number of beams

DIRECT I HI-SPEED WARPING MACHINE

COMPONENTS OF WARPING MACHINE

CREEL:

1. Cone Holder : Hold the cone or arrange the cone in the creel.

2. Yarn Guide : To guide the yarn.

3. Tension Rod : Maintain yarn tension by upper & lower disctensioner.

4. Ceramic Guide Disc : To guide the yarn from creel to warping m/c.

5. Auto Stop Sensor : To sense the breakage yarn.

6. Creel Panel Board : Display where the yarn break

Creel:

FUNCTION OF COMPONENTS OF CREEL

Function of components of creel:

1. Cone or cheese spindle for high speed warping.

2. Thread guide: To pass through the yarn in the reqd way.

3. Tensioner: To keep the yarn always in a uniform tension.

4. Yarn cleaner: To remove various faults of yarn like slubs, neps etc.

5. Suction fan or blower: To remove the dirt & dust from the yarn.

6. Breakage indicator: To indicate breakage in package.

7. Stop device: To stop the m/c when yarn will be broken.

Control device:Similar to winding, warp yarns are threaded through tension devices , stopmotions, leasing rods and the reed. The stop motion electrically links each warpend to the warper braking system; when a warp end breaks, the warper stops. Alight indicates the location of the broken end. The warping process is generallyirreversible, unwinding, of the beam would cause yarn entanglement. The stopmotion device which can be mechanical or electronic for quick response, is usuallylocated near the creel.Fans are used to prevent lint accumulation when warpingstaple yarns.

High Speed Warping m/c Setting:

Use of High-Speed Warping Machine

• Producing one color fabric like gray fabric

• For producing one/single color fabric

• For the same count of yarn

• Example: Shirt , Pant , Polo Shirt etc.

Sectional Warping m/c.

•Sectional warping is a process of preparing warp beam over two stages.

•First, yarns are wound in narrow tapes on a large drum.

•Second, the rewinding of the warp onto a beam is performed.

Sectional warping machine

Main parts :

•Creel

•Drum or dresser

•Warping comb

•Warping carriage

•Leasing and splitting devices for sizing

•Beam carrying chuck

•Guide

•Levelling roller

Features of sectional warping

• To produce fancy fabric of different colors.

• Hand weaving used in sectional warping.

• To produce weavers beam from small amount of warp yarn.

• To produce weavers beam from twisted yarn.

• To produce weavers beam from which do not required any sizing material to

be applied before weaving.

• Weavers beam can be formed immediately after.

• Production is less, so it is costly process.

• Yarn tension can not be kept uniform.

• A tapered beam or drum is used.

Process Flow: Dispo

Yarn from store

Creeling

(According to warp plan)

Machine setup

Section wise warping

BeamingWarp width:

Total Ends Warp Width

Below 7200 1800 mm

7200 2000 mm

Above 7200 2100 mm

Process Flow Chart Sectional Warping Machine

SCHEMATIC DIAGRAM OF DIRECT WARPING MACHINE

HEAD STOCK OF SECTIONAL WARPING MACHINE:

HEAD STOCK OF SECTIONAL WARPING MACHINE:

CREEL DIAGRAM

Should meet the following requirement:

1. The tension of all wound ends must be uniform and possibly constant during all the

time of withdrawal from supply packages, otherwise the rate of breakage will be

increased & the structure of the ready cloth will be impaired.

2. Warping should not impair the physical & mechanical properties of yarn. The tension

should moderate to allow the yarn to completely retain its elastic properties & strength.

The yarn should not be subjected to sharp abrasive action.

3. The surface of warping package must be cylindrical. Therefore, the spreading of yarn

(density) throughout the whole width of warping must be as uniform as possible.

4. A pre determined length of warping should be observed.

5. The production rate of warping should be as high as possible.

REQUIREMENT OF WARPING

1. The yarns in the sheet should be in uniform spacing.

2. The yarns in the sheet should be in uniform tension.

3. The yarns in the sheet should be of a predetermined length.

4. The sheet should be containing a predetermined number of ends.

5. There should be no broken ends in the beam.

REQUIREMENT OF WARPING

Warp off centre of the beam:

Due to not carefully placing of creel wraith and flanged beam.

Remedy: Beam and wraith placed properly.

Ridgy or uneven warp beam:

This effect due to

Winding of small no of ends on larger beam.

When the dents are bent or the spacing between dents is uneven.

Mixed count.

Remedy: Higher no of ends be used.

Crossed ends:

Due to

Faulty knotting after yarn breakage.

Tying of broken ends.

Loose warp.

Remedy: Knotting and tension controlled.

Faults & Remedies of Warping:

Snarl formation in the warp:

Due to

Over tension.

Improper twist.

Position of guide.

Remedy: By proper tension and twist.

Missing ends:

Due to

Faulty stop device.

Exhausted cone or bobbin.

Absence of cone or bobbin on creel.

Remedy: By correct stop device is used

Hard beam:

Due to high tension.

Remedy: Tension and pressure maintained.

Faults & Remedies of Warping:

Unequal length :

Due to faulty measuring device.

Remedy: correct measuring device.

Broken ends:

Remedy: To be joined carefully the yarn.

Warp ends round the creel peg.

Unequal length of warp.

Unequal size or weight of cone or cheese in the creel.

Lapped ends.

Piecing.

Soft end on the warping beam.

Warp ends round the creel peg(spindle) and results broke.

Faults & Remedies of Warping:

Causes of yarn breakage in warping:

1. Weak yarn.

2. Sloughing off.

3. Over lapping.

4. Knots/ bad splice.

5. Slubs.

6. Loose yarn.

7. Pig tail.

8. Cut yarn.

9. Bad tip cone.

10. Short cone

Causes of yarn breakage in warping: