Textile industry

The textile industry is primarily concerned with the production of yarn, and cloth and the subsequent design or manufacture of clothing and their distribution. The raw material may be natural, or synthetic using products of the chemical industry.

The industrial processes


Cotton is the world's most important natural fibre. In the year 2007, the global yield was 25 million tons from 35 million hectares cultivated in more than 50 countries.
There are five stages
  • Cultivating and Harvesting
  • Preparatory Processes
  • Spinning
  • Weaving
  • Finishing


Spinning


Spinning is a major industry. It is part of the Textile manufacturing process where three types of fibre are converted into yarn, then fabric, then textiles. The textiles are then fabricated into clothes or other artifacts. There are many three industrial processes available at this time used to spin yarn, and a handicraft community that use hand spinning techniques. Spinning is the twisting together of drawn out strands of fibres to form yarn, though it is colloquially used to describe the process of drawing out, inserting the twist, and winding onto bobbins.


Most spinning today is done using break or open-end spinning, this is a technique where the staples are blown by air into a rotating drum, where they attach themselves to the tail of formed yarn that is continually being drawn out of the chamber. Other methods of break spinning use needles and electrostatic forces.This method has replace the older methods of ring and mule spinning. It is also is easily adapted forartificial fibres.
The spinning machines takes the roving, thins it and twists it, creating yarn which it winds onto a bobbin.
In mule spinning the roving is pulled off a bobbin and fed through some rollers, which are feeding at several different speeds.This thins the roving at a consistent rate. If the roving was not a consistent size, then this step could cause a break in the yarn, or could jam the machine. The yarn is twisted through the spinning of the bobbin as the carriage moves out, and is rolled onto a cop as the carriage returns. Mule spinning produces a finer thread than the less skilled ring spinning.
  • The mule was an intermittent process, as the frame advanced and returned a distance of 5ft.It was the descendant of 1779 Crompton device. It produces a softer less twisted thread that was favoured for fines and for weft.
  • The ring was a descendant of the Arkwright water Frame 1769. It was a continuous process, the yarn was coarser, had a greater twist and was stronger so was suited to be warp. Ring spinning is slow due to the distance the thread must pass around the ring, similar methods have improved on this; such as flyer and bobbin and cap spinning.
Sewing thread, was made of several threads twisted together, or doubled.
The pre-industrial techniques of Hand spinning with spindle or Spinning wheel are continue to be practised as a handicraft or hobby, and enable wool or unusual vegetable and animal staples to be creatively used.
  • Checking
This is the process where each of the bobbins is rewound to give a tighter bobbin.
  • Folding and twisting
Plying is done by pulling yarn from two or more bobbins and twisting it together, in the opposite direction that in which it was spun. Depending on the weight desired, the yarn may or may not be plied, and the number of strands twisted together varies.

Weaving


Weaving is a textile craft in which two distinct sets of yarns or threads are interlaced to form afabric or cloth. The threads which run lengthways are called the warp and the threads which run across from side to side are the weft or filling.
Cloth is usually woven on a loom, a device that holds the warp threads in place while filling threads are woven through them. Weft is an old English word meaning "that which is woven". A fabric band which meets this definition of cloth (warp threads with a weft thread winding between) can also be made using other methods, including tablet weaving, back-strap, or other techniques without looms.
The way the warp and filling threads interlace with each other is called the weave. The majority of woven products are created with one of three basic weaves: plain weave, satin weave, or twill. Woven cloth can be plain (in one colour or a simple pattern), or can be woven in decorative or artistic designs, including tapestries. Fabric in which the warp and/or weft is tie-dyed before weaving is called ikat.
Though traditional handweaving and spinning remain popular crafts, nowadays the majority of commercial fabrics in the West are woven on computer-controlled Jacquard looms. In the past, simpler fabrics were woven on dobby looms, while the Jacquard harness adaptation was reserved for more complex patterns. Some believe the efficiency of the Jacquard loom, with its Jacquard weaving process, makes it more economical for mills to use them to weave all of their fabrics, regardless of the complexity of the design.





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