Today we will discuss about the processes involved in making woven fabric.
Woven fabrics are made by the intersection of two sets of straight threads which cross each other at right angles. The yarn that run lengthwise of the fabric is called the warp yarn and the yarn that intersects the warp yarn widthwise is called the weft yarn. The two threads are interweaved at 90 degree angle to each other to form the woven fabric
The processes involved in making woven fabric are, winding, warping, sizing, drawing and denting, and finally looming.
Winding is the process of transferring yarn from one package to another suitable package. Usually yarn from spinning mill comes in the form of cone. To prepare the weft yarn, the yarn from the cone package is transferred to pirn package so that it can be set in the shuttle of the shuttle loom. This is done by the process of winding.
Then all warp yarn needs to be either in cheese package or cone package form for the warping process. The cheese or cone package needs to be wound in a particular form, so that during the warping process, the yarn comes out of the package in a smooth way, and is not damaged or torn due to tension.
Warping is the process by which the warp yarn from the cheese or cone packages are wound parallelly on a warp beam. First the cheese packages or cone packages are set on the creel of the warping machines. Then the threads from each package is passed through various guides and laid parallel on the beam. Then as driving drum rotates the beam, the warp yarns are parallelly wrapped on the the beam.
After warping, the warp beams are taken to the sizing machine.
Sizing is the process by which a protective adhesive coating is done on the yarn surface. This process increases the elasticity, strength, smoothness, weight, and frictional resistance of the yarn. This is the most important process that maximizes the production efficiency of the woven fabric making process.
Two or more warp beams are placed on the sizing machine. Yarns from each warp beam are set parallel to each other. This increase the number of warp yarn per inch. Then these yarn are passed through sizing unit. In the sizing unit, the sizing chemicals are coated on the the yarn surface by the help of rollers and padders.
After application of the sizing chemicals, the yarn is then passed through the drying unit. The drying units contains multiple stainless cylinder which are heated by steam. The yarns are passed through the cylinders and this way the yarn is dried, and the sizing chemical is set on the yarn surface.
After the drying unit, the yarns are passed through the separating unit. Here, by the help of lease rods, the yarns are separated. Then all the yarns are passed through the V wraith and set on the beam, maintaining the warp yarn per inch or ends per inch required in the final fabric. This beam is called the weavers beam
Then the weavers beam is taken for drawing and denting.
The process of inserting the warp yarn, from the weavers beam, through the dents of the reeds of the loom, according to the fabric design pattern, is called drawing and denting. This is the process by which the design of the fabric is set.
After this process, the reeds and the weavers beam is set on the loom. Loom is the machine by which the warp yarn and weft yarn are interweaved at 90 degree angle to from the woven fabric.
The Heald frame moves up and down to create a gap between the warp yarns according to design pattern. This movement is called shedding.
The weft yarn is passed through this gap at 90 degree angle. This process is called picking. In shuttle loom, shuttle is used to pass the weft yarn during picking. In air jet loom, air is used to pass the weft yarn during picking.
Lastly, by the process of beating, the inserted pick or weft yarn is pushed into the already woven fabric at the point which is known as the fell of the cloth.
This is a very simple overview of how woven fabric is made.
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