Fabric Club Of BD: BASIC DISCUTION ABOUT WARPING CREEL

BASIC DISCUTION ABOUT WARPING CREEL

Labels: Weaving Manufacturing Technology | at 3/06/2011 04:57:00 PM

Creel

The creels are simply metallic frames on which the feeding bobbins are fitted. They are outfitted with yarn tension devices, which in modern machines are provided with automatic control and centralized tension variation.

The creels are the frames on which the cones which feed the warped are pinned. The number of cones depends on the type of fabric to be produced. The yarns are wound side by side and parallel one another on the beam, if possible with the same tension.

The tension devices fitted on the creels are designed to obtain this uniform tension.

The cone position and their accessibility are two important factors for the operator.

The latest creels have yarn tension devices with automatic control and centralized tension variation. These devices allow also processing a wide range of yarns on the same creeling plant.

Warping is a low yield operation owing to the time needed for creeling. Various solutions have been conceived to minimize this time, by trying to perform the creeling of the full cones while the warped is running.

The trolley creels have a yarn cutting and knotting device which can cut 720 ends in 50

Seconds and knot them in 10 minutes.

This system is suitable for staple fibre yarns in counts ranging from Nm 10 to Nm 140. Trolley creels have generally two series of trolleys: one in operation and one waiting for being creeled.

For staple fibre yarns also mobile creels are used. These can be equipped with a series of trolleys for the transport of the reserve cones; as an alternative, two creels with stationary cone carrier frame are used together with the warped. In both cases the bobbins are creeled during warping.

Another solution employs swivel frames. While yarns are unwound from the bobbins placed in the inside of the creel, it is possible to creel at the outside of the creel the new lot of cones.

For luxury yarns, the so-called magazine creels are used, which enable to creel two cones per creeling position and to piece head-tail end of two cones.

For the creeling of dyed yarns, a programmable electronic system has been studied. A warning light indicates the position where the yarn of a certain color must be creeled.

This allows a time saving of 60% in creeling and avoids patterning faults and double ends.

The creels are equipped with yarn break detectors which warn the operator through display at the start of the creeling operation. When the yarn breaks, the sensor stops the warped and indicates through signal lights the position of the yarn breakage.

All types of creels can be equipped with air-blowing trolleys to maintain tensions clean.

FIG: Warping creel

Types of creel

1. *Single ends creel

a) Truck creel

b) Duplicated creel

2. *Magazine creel

3. *Swivel frame creel

4. *Mobile creel

5. *V-Shaped creel

6. *Rotating frame creel

7. *Unrolling creel

Single ends creel

Single package is associated with each end being wound on beam. The creel packages contain same amount of yarn.

FIG: Single ends creel

a) Truck creel: In travel creel, head stock is rigid and creel is variable.

b) Duplicated creel: In duplicated creel, head stock is variable and creel is fixed.

FIG: Truck creel

Magazine creel

This invention has general reference to means or equipment such as used in the textile arts for the grouped resolvable support of threads or yarn supply package or spools for beaming or spools for beaming or re-spooling, with the tail end of the threads or yarn of one package or spool connected or tied over to the leading end of another package or spool to speed up the beaming, re spooling or as associated operation.

More specifically the instant improvement re-late to yarn package or cone supporting creels of the species commonly designated as vertical type magazine cone creels; such creels including multiple upright or standards having vertically adjustment opposed directed horizontal affording rotary support for active and inactive pairs of package or cones that have the tail end of the active cone tied up or connected to the leading end of the associated inactive cone.

Creel of the above specified type while satisfactory in many respects are disadvantageous when an active package or cone become exhausted in as much as the operator must exercise considerable care in making the replacement, with an attendant waste of time due to the difficulty experienced in bringing the exhausted package or cone carrier member out into the clear where the operator can make said replacement without reaching over, fouling or entangling any of the running threads or yarn.

FIG: Magazine creel

Swivel frame creel

This type of creel was designed as a variation of the mobile creel to enable the creeling up of bobbins which, owing to their heavy weight (5 to 25 kg), cannot be pinned on trolleys. Each bobbin holder is double-sided: the threads are unwound from one side, while a new series of bobbins is creeled up on the other side.

FIG: Swivel frame creel

Mobile creel

This creel type is similar to the standard creel, but is formed by trolleys which can be taken individually out of the creel.

With mobile creels, individual bobbin trolleys enter the one after the other. Reeling up of the bobbins can be performed outside the creel while the preceding sets of bobbins are being used.

This reduces considerably the waiting time. The mobile creel comes in handy especially when there is insufficient room to permit the use of two standard creels.

1=Creel frame, 2=Bobbins trolleys with bobbins, 3=Threads brake, 4=Threads brake, 5=Stop motion.

FIG: Mobile creel with outside draw off.

V-Shaped creel

V-Shaped creel are shaped like are a V when viewed from above; this shape reduces the number of deflections and guide elements. Also the time required to repair a thread break is reduced and creeling up can take place on the inside during the warping process V-Shaped creel take up pore space than normal ones, so the inside section is used often used for storage.

1=Creel frame, 2=Bobbin carrier with bobbins, 3=Threads brake, 4=Threads brake creel, 5=Stop motion

FIG:V-Shaped creel

Rotating frame creel

On rotating frame creel the bobbins are placed on rotating frames. In fig illustrates a rotating frame creel with outside draw-off. While the threads they are being draw-off during the warping process, new bobbins can be creeled up on the inside. If the outside bobbins are empty, the frame is rotated and a new pulled in. This type of creel reduces stoppage times during bobbin change.

1=Creel frame, 2=Rotating frame with bobbins, 3=Threads brake, 4=Threads brake creel, 5=Stop motion.

FIG: Rotating frame creel.

Unrolling creel

In situation in which elastic materials are being warped in section onto warp beams from individual bobbins, an even yarn tension can only be achieved using a positive thread feed. Cylindrical bobbins on one or more rollers that are turning synchronously in the same direction are unwound tangentially.

1=Lever, 2=Bobbin, 3=Take-up roller, 4=Stop motion,5=Pre-tensioning device,6=Spacer reed,7=Warped.

FIG: Schematic view of an unrolling creel placed parallel with the warping machine.

Importance of warping creel

In the same time a large amount of yarn package, cone or cheese are wound and unwound.
It ensures well decorated distribution of yarn on the warp beam.
By creeling all of the yarns are separated from each other.
By creeling all of the yarns of warp beam achieve a perfect tension.