Preparing Warps and Wefts for Weaving
The warps form the basic structure of fabrics. As such, they are made to pass through many operations before actual weaving is done. These operations include spooling, warping and slashing. In spooling, the yarn is wound on larger spools, or cones, that are placed on a rack known as a creel. From the creel, the yarns are wound on a warp beam, which looks like a huge spool. These lengths of hundreds of warped yarns lie parallel to one another. These yarns are unwound for slashing or sizing.
The yarn is coated with sizing with the help of slasher machine. Slashing prevents chafing or breaking of yarns during the weaving process. Sizing is either starch based or a synthetic like polyvinyl alcohol or water-soluble acrylic polymers. The sized yarns are then wound on a final warp beam and are ready for the loom.
The filling yarns experience less strain during the weaving process. Their preparation includes spinning them to the required size and giving them just the right amount of twist desired for the kind of fabric they will be used.
Preparation of weaving machines
To obtain satisfactory weaving performance, it is essential to have not only a correct yarn preparation but also an efficient organization which permits to have warps available at the right moment, thus avoiding any dead time with style or beam change. All these prerequisites aim at ensuring to the weaving mills a sufficient flexibility and at permitting them to cope promptly with a variable market demand.
Currently, several weaving mills have installed weaving machines which enable to perform the quick style change (QSC), leading to a considerable reduction of the waiting time of the machine.
The following chart presents the possible alternatives for the preparation of the weaving machine: