Spinning is a very ancient activity, and humans have understood how to spin small fibers into long threads, which are then woven into fabric, since prehistoric times. Spinning generally involves twisting animal or vegetable fibers to produce a continuously and infinitely expanding thread ideal for weaving.
Cotton spinning is the technique of spinning random short fibers, such as raw cotton, into endless -Cotton yarn or cotton blend yarn can be spun. In spinning, disordered fibers are transformed into aggregates. Compressed cotton bales reach the cotton mill as raw cotton. The fibers are blocky and disorganized, with various impurities and imperfections. Therefore, when spinning, it is important to first loosen and then join, that is, break the superfluous join the fibers and remove them. Impurity defects are arranged axially to avoid splinters of the gto produce the desired thickness, which are then twisted into cotton yarn accordingly.
Clearing Garnishing, carding, combing, drawing, roving and spinning yarn are the main steps in the spinning process. Each stage of the spinning process is detailed below:
Cleaning Process
The cleaning process removes most of the impurities, flaws and short fibers in the raw cotton that are unsuitable for spinning are removed. It involves taking the raw materials out of the cotton bales, combining them evenly, opening them into small blocks of cotton or small bundles of cotton, and removing any impurities or imperfections. Layers of cotton of different widths, thicknesses and weights are then combined and wrapped into rounds.
The main task of the cotton cleaning processBlending
Blending raw cotton requires the blending process as well as the blending quality. Blending loose cotton fibers, blending Ssplintering and mixing weights in cotton sacks are used in spinning today. Particular attention should be paid to the uniform blending of raw cotton of different grades, recycled cotton and recycled cotton.
The more regular the blending, the better it can resolve color differences and color shifts, improve uniformity, and improve the coefficient of variation in breaking strength individual yarns. Alternative cotton opening and scouring techniques can be used with raw cotton to increase yarn quality, with significant differences in impurity concentration, and then blended on the drawframe.
Opening
Opening is necessary to ensure the blended cotton components are thoroughly blended are mixed, impurities are removed and the fibers are simply fibrillated. Depending on the opening state of the lining material, the opening can be marked as \"free\".or \"Halt\".
1. Unrestricted access
Free opening refers to raw cotton that accepts the opening mechanism in the free state, which can be further divided into free tearing and free blowing.
2. Hold and Release
The raw material is fed into the machine in the hold state also affected by the opening mechanism, a process known as hold and open. In raw cotton, it can be divided into two modes of action: hold and hit and hold and card. The results of opening and removing impurities are clearer. Opening is robust, but fiber damage and contamination shredding are more severe than free opening.
During the opening process, the principle of \"slow first, then fast, progressive opening and minimal fiber damage\" should be followed. In the process of removing impurities should be heavy, reRelatively large and easily breakable impurities as well as low fiber adhesion are first removed according to the technological principle of \"early falling and splintering\".
Machines involved in the cleaning process:
cotton opener, cleaning machine, cotton blending machine, lapping machine.
Carding process
Carding is the process whereby tiny bundles of cotton are broken down into a single fiber state by movement of the needle surface, i.e. hImpurities and non-spinnable short fibers are moved, making the fibers parallel and straight, and finally a sliver is rolled into cans.
After cotton cleaning, the fibers in the cotton roll or loose cotton are mostly in the form of loose cotton blocks and cotton bundles and contain 40 to 50% impurities, the majority of which consists of small, strongly adherent fibrous impurities (e.g. broken seeds with fibers, seed residues, soft seed coats, cottonneps, etc.) , so the fiber bundle must be completely broken down into individual fibers and the fine impurities remaining in them removed so that the fibers remain intact. The main tasks of the carding process: Carding: In order to cause as little damage as possible to the fibers, the lining cotton layer is carded carefully and thoroughly to separate the bundled fibers into individual fiber states. Impurity Removal: After adequate fiber separation, completely remove remaining impurities and defects. Mixing: In the single fiber state, ensure that the fibers are thoroughly mixed and evenly distributed. Tapes: Make consistent tapes to specific specifications and quality standards and store them in tape canisters on a regular basis. Card
The card is responsible for completing the carding process. The extent to whichm cotton bundles are broken down into individual fibers on the card is directly proportional to yarn count and evenness. The effect of impurity removal has a significant impact on neps contamination and yarn evenness. The card has the highest noil rate among the individual machines of the carding system, and the noils have a certain number of spinnable fibers, hence the amount and quantity of noils of the card are directly proportional to the amount of cotton used.
Combing process
The combing process takes place before cotton, wool and silk fibers are processed into textiles. Removes impurities and short filaments in the fibers with a combing machine. Compared to carded textiles, the texture, Washability and durability of the fabric produced by this method is significantly improved.
The main tasks of the combing process are the removal of impurities : clean the fibers of neps, impurities and fiber defects. Carding: Further separates the fibers and excludes short fibers of a certain length. Pulling: reduce the thickness of the sliver and improve the parallel straightness of the fibers. Slivers: Create cotton fibers that meet specifications.Comber
Carding the two ends of a fiber bundle alternately with a machine equipped with surface carding needles to remove unsuitable short fibers. The combing process improves the evenness of the fiberlengths, separates kinked fibers into a uniform state and removes impurities and fiber knots (neps, wool grains, hemp grains, cocoon skins, etc.) contained in the raw material. Commonly used in the manufacture of fine and high quality yarns. The woven fabric features clean lines, minimal streaks and shadows, and an even surface due to the uniform dryness, smoothness, and greatly improved strength of the combed yarn.
Drawing Process
In the previous The fiber material was opened and carded, resulting in a continuous strip-shaped semi-finished product, a so-called fiber strip, also known as raw strip. After preliminary Regardless of the orientation and alignment of the fibers, the raw sliver produced by the card has the preliminary shape of a sliver. On the other hand, the unevenness of the carded sliver is quite large and the fiber organization in the carded sliver is disordered, with mostFibers are hooked. If this carded sliver is immediately spun into spun yarn, the spun yarn is of poor quality. Therefore, the carded sliver needs to be mixed before further spinning to improve the uniformity and fiber condition.
The main tasks of the drawing process
(1) Combine: To make a sliver, feed 6-8 slivers into the drawing frame a. The unequal length of the sliver can be solved by the thick and thin areas. The individual slivers have the possibility of overlapping each other. Rate. The raw sliver has a weight non-uniformity of about 4.0%, and the cooked sliver should have a weight non-uniformity of less than 1% after merging.
( 2) Elongation: The sliver is stretched and applied to the or thinnedThe original level and at the same time the condition of the fiber is improved by the stretching, so that the hooks and rufflesl fiber can be further straightened and parallelized and the small cotton bundle is further separated into individual fibers. By changing the draft ratio , the quantification of the cooked sliver can be effectively controlled to ensure the weight deviation and weight non-uniformity of the spun yarn are within the standard.
(3) Blending: The repeated merging process is used to further to be realized The mixing of individual fibers ensures that the mixed cotton composition of the sliver is homogeneous and the yarn quality is stable. Since different fibers have different drying properties, slivers composed of different fibers can be mixed on the draw frame to thoroughly mix the different fibers. A good way to create color variations, especially when using man-made fibers and cotton.
(4) Sliver: Platzieren the sliver produced by the drawing frame in a regular circle in the sliver tube so that it can be transferred and stored for the next operation.
Roving Process
The main objective of the roving process is to give the sliver a correct twist or false twist by twisting or twisting to give the roving enough strength to withstand the stress of winding and unwinding and is beneficial for the drawing process on the spinning machine. Wind the roving into a specific packaging shape to facilitate transportation and storage, adjust the criteria of the spinning machine to the feeding form, and improve the efficiency of the spinning machine.
Main task
Drawing: The sliver is drawn and thinned until it is the size of a roving. Twist: To increase the strength of the roving, add a twist to it. Winding: Thread the bobbin with the twisted roving. Spinning process
The spinning prozess is the last step in the spinning production process. In doing so, the roving is spun into a spun yarn with a certain unique number that meets the quality standard or customer needs and is suitable for twisting, weaving or knitting. The spinning machine is the most important piece of mechanical equipment.
Spun yarn serves the following purposes: Elongate the yarn to increase the capacity of the yarn package and the production efficiency of the subsequent process. Remove imperfections and impurities from the yarn to increase its quality and strength. The main tasks of the spinning processDrawing: The supplied roving or sliver is evenly stretched by the spun yarn and thinned to the corresponding specific number. Twisting: The appropriate twist is given to the drawn strands to make them come alive. The yarn has physical and mechanical properties such as strength, elasticity, luster and hapticik. Winding and Forming: To facilitate transportation, storage and future processing, the spun yarn is wound onto the bobbin according to the specific forming requirements.