Warping and Types of Warping

Warping:

1.     The preparation of warp yarn is more demanding and more complicated than that of the filling yarn.

2. Each spot in a warp yarn should undergo a few thousand cycles of different tensions applied by the weaving machine.
3. In general terms, warping is transferring many yarns from a creel of single-end packages forming a parallel set of yarns wound onto a beam or a section beam.
4. Today warping machines will process every kind of materials, including course and fine filament and staple yarns.
5. Warping is aimed at preparing the weaver’s beam to be set up on the weaving machine depending on the kind of intermediate carrier used, the industrial warping process can be
6. carried out according to two totally different technologies: Sectional warping (conical drum or dresser warping).
7. Beam warping or direct warping (preparatory beam warping).
8. Modern weaving machines have placed increased demands on warp preparation due to faster weaving speeds and the use of insertion devices other than the shuttle; warp yarn must have uniform properties with sufficient strength to withstand tension and frictional abrasion during weaving, uniform tension is necessary so that all the warp ends behave the same way.
9. The tension on the warp yarns is maintained relatively low, due to the high inertia of the beam, it is difficult to stop the beam suddenly once an end is
10. broken, however, the beam should be stopped before the broken end reaches the beam.
11. Breaking strength of yarn is that the most significant property of yarn as it represents the main parameter for physical quality control.
12. Breaking strength of yarn depends on many different factors, namely the strength of the fibre, length of the fibre, micronaire, and uniformity.
13. The yarn speed should be kept as constant as possible throughout warping.
14. In indirect warping a constant speed drive is generally sufficient to provide fairly uniform yarn speed, for some filament yarns variable speed drive is chosen for friction drive would cause problems.
15. Warp yarn tension A creel for supplying yarns from a plurality of respective packages to a take-up machine, like a warp winder, includes a support defining various supply stations
16. carrying the yarn packages, respective tension-sensing deflectors at the stations, and guides for directing the yarns from the respective packages over the respective braking surfaces and around the respective deflectors.

Warping

The parallel winding of warp yarns from different winding packages like cones, cheeses, spools, Warper’s bobbin into a sheet form is called Warping.

Warping is the parallel winding of yarn from the cone or the cheese package on to a warp beam. The operation of winding warp yarns onto a beam usually used in preparation for slashing, weaving, or warp knitting. Also called warping.

It is the process of preparing a double flange beam of warp yarns arranged parallel to each other.

The objective of the warping process is to convert the yarn packages into a Warper’s beam having the desired width and containing the requisite number of ends.

The yarns are wound onto the Warper’s beam in the form of a sheet composed of parallel bands of yarns, each coming out from a package placed on the creel.

1.      Warp preparation transfers the ground yarn from the spinner’s cheeses onto a ground beam and the pile yarn onto a pile beam

2.      Cones of warp yarns are arranged in a framework called a creel and wound directly onto each beam.  This process is called direct warping

3.     There are hundreds of (up to 600) cones per warping machine

Types of Warping:

1.  Beam/Direct warping • (Gray/Monocolour fabric)

2. Sectional/Indirect warping • (Warp patterns: Stripes and Checks)

3. Ball warping • (Denim fabric)

Beam/Direct warping:

1.     It produces the Warper beams that are combined together as a single weaver's beam in the next process of sizing.

2.     A warpers beam may contain 500-1000 ends.

3.     Direct warping is suitable for grey or mono-coloured warps that require sizing.

4.     Components of Warping Machine are:

a.       Creel;

b.     Headstock;

c.      Control devices.

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 & a lower disc tensioner.

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

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

6. Creel Panel Board: Display where the yarn break.

Creel is a stand for holding the supply packages in the form of wound packages.

1.     It enables to hold the supply packages in the proper position for warping.

2.     No single type of creel can give the same beaming efficiency for different types of yarns.

3.     Different types of creels are:

• V-creel;

 • Magazine creel;

 • Rectangular creel;

• Automatic Creels;

• Truck  creel;

• Special Creels.

• Continuous chain creels

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 the required length of the beam or in case of yarn breaks.

9. Electrical Panel Board: To give the automatically controlled function.

Beam Warping (Quality aspects)

1.     Exact thread guidance

2.      No crossed threads

3.      Cylindrically wound beams: no slip between press roller and yarn package

4.      Warp length accuracy within 1 per thousand

5.      No cutting-in by threads on the comb

6.      Fewer rolled-in ends through short braking distances

7.      Short braking distance

8.      Simple insertion of threads into the comb

9.      Workplace designed according to ergonomic principles

Sectional warping:

1.     It is suitable for all warp patterned fabrics e.g. Stripes and checks.

2.     Warping is carried out section by section.

3.     A single beam is prepared which may or may not be sized.

4.     Sometimes this process is carried out for 2-ply synthetic warps where no sizing is needed.

5.     It is a two-stage process. Warping onto the drum and Beaming.

6.     Creel capacity can be lower.

7.     The yarns are laid section-wise, starting from the conical base side.

8.     The first section is supported by the conicity of the base and the subsequent sections supported by the connect formed by the preceding section.

Sectional Warping (Quality aspects)

The newly developed machine with its reed headstock integrated into the machine superstructure allows production speeds never previously achieved, thanks to its innovative control system.  The machine has the following special technical features:

1.     Production of warp sections with a minimum width of 4 mm or (depending on yarn fineness) minimum 12 – 24 threads.

2.     With maximum end numbers of 480 -560 threads and a section width of up to 150 mm, the machine can be fine-tuned for flexible production.

3.      The time for each thread separately at a lease or sizing split is 7 seconds per separation process 

4.      A maximum warping speed of 750 m/min allows production to be optimized to suit yarn properties.

5.      The perfect thread tension between creel and machine in the warping process ensured by the use of a proven section tension control and a controlled beam tension system forms the basis for warp quality that meets the highest requirements.

6.      The machine is available with a working width of 2,200 mm for the traditional clothing sector and 3,600 mm for decorative fabrics and furniture coverings.

Ball warping:

1.     It is a process in which warping is done in rope form.

2.     A ball warp beam is prepared for subsequent processing.

3.     It is suitable for denim fabric manufacturing, involving rope dyeing process.

4.     It is also a 2 stage process; Ball warp winding and Long chain beaming.

5.     Dyeing is done before beaming operation.

6.     Initially, the warps are wound in rope form of a cylindrical barrel.

7.     Dyeing is carried out in the rope form of the warp yarns.

8.     In the second stage: (Long chain beaming), The ends are spread to open width form.

Warping is the arranging of yarn threads in long parallel lengths of equal tension, onto a beam in preparation for weaving.

During the warping process cones of yarn are placed onto a rack called a creel. From this creel yarn passes through tension and spacing devices and through a leasing reed, which separates the yarn threads and keeps them in the correct order before being wound onto a warping balloon.

In the wool, industry warping is carried out on a sectional machine where each section of warp threads is wound onto the belonging alongside previous sections.

When the correct amount of yarn has been added the warp is removed from the balloon and transferred onto a warping beam ready for the weaving process.

Flow Chart of Warping

Requirements of Warping

To produce a quality beam suitable for the following must be accomplished: 

1.     The individual ends of the sheet should be spaced uniformly across its full width. 

2.     All the ends of the sheet should be wound at almost uniform tension. 

3.     The density of the wound yarn beam should be uniform across the width & from start to the end of winding the sheet. 

4.     The yarn breakage during warping should be as minimum as possible. 

5.     The density of the beam should be controlled not by increasing yarn tension, but by adjusting the pressure roller on the beam in case of spindle driven beam. 

6.     The yarn should not get damaged during warping; this can happen if the drum surface is not smooth &/or the parts in the yarn path have cut marks. 

7.     The yarn sheet or the beam should not have faults, such as missing ends, cross ends, slack ends, fluff or wild yarn, high variation in tension between ends, damaged flanges etc. That will cause end break or defects at the subsequent process. 

8.     Warping should not impair the physical & mechanical properties of the yarn. 

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

10. A predetermined warping length should be observed.

Faults of Warping

1.     Warp off centre of the beam

2.     Ridge or uneven warp beam

3.     Cress ends

4.     Snarl is the warp

5.     Missing ends

6.     Unequal length of warp

7.     Hard beam

8.     Unequal size or weight of the package

Manufacturer of Warping Machine:

1.     Benninger

2.     Scorer

3.     Sucker Muller Hacoba

4.     Yamada

5.     West Point

6.     Karl Mayer

7.     Suzuki

The purpose of warping is to prepare defect free Warper beam of spun yarn to size. Technical Details: ·         Maximum speed: 1200 m/ min ·         Dye beam capability (with positively driven overrun Roller) ·         Direct Warper combined with V creel or parallel creel ·         Siemens NT systems Applications: ·         Shirting, bottom weights, home textiles and apparels  Key Features: ·         Meter counting system ·         Precise tension control at creel and at the beaming head ensure production of the perfect         Warper beam ·         End uncrossing device ·         Dye beam device with the laser measuring system           Direct Warper beamer is combined with V-creel having a free thread run between tension and comb    Siemens - Process control system - Operator Interface IPC /Touch screen 12.1", ethernet    Interface for networking and connection for the relevant data acquisition and Teleservice ·         Raw Material: ·          100% cotton, regenerated, synthetic, wool and their blends ·         Key Benefits: ·          Meter counting system ensures the accuracy of warp length on beam within +/- 0.1% ·          Precise tension control at creel and at the beaming head ensure production of        the perfect ·         Warper beam ·          Dye beam device ensures the production of warp beam with gentle and uniform tension. ·         It also maintains required yarn density on beam at the same level with the help of positively driven ·         Overrun roller ·          End un-crossing device -Order of the ends are restored. ·          Direct beamer with V - creel increase production speed and productivity ·          Clean Master helps to keep the yarn dust free, which in turns reduces the downtime        and faults