Polyester yarn

20/2 20/3 40/2 50/2 60/2 60/3 100% polyester yarn

Technical measures of systematic control of yarn hairiness

1、 Flower cleaning process

The key point of the cleaning process is to reduce the fiber damage. In the case of low impurity content of raw cotton, reduce the speed of each hitter and enlarge the distance between holding and striking points, which will improve both hairiness and neps.

Keep the air flow unobstructed without choking or traffic jam. Choking is the main factor that causes the neps of the cords, and these cords will produce a large number of short fibers in carding, which will greatly increase the hairiness; at the same time, the smooth air flow can remove part of the short fiber dust from the dust cage, which is conducive to the subsequent processing.

Keep a certain humidity, make the cotton roll to the carding in the state of dehumidification, which is conducive to carding, reducing lint and neps. In fact, the moisture regain of cotton roll is an important index for air conditioning.

2、 Carding process

The technological idea is to reduce the damage, eliminate the short pile and improve the fiber's straightness and parallelism.

Measures to be taken: adopt lower speed of stabbing roller, larger speed ratio of cylinder and stabbing roller, appropriate distance between stabbing roller and cotton feeding plate, adopt larger distance between cylinder and upper front cover plate for forward rotation of cover plate, and adopt larger distance between cylinder and upper rear cover plate for reverse rotation of cover plate, so as to properly improve the operation speed of cover plate.

The key point of the equipment is to ensure the mechanical state and needle cloth state. After the speed reduction of the thorn roller, the inspection of the status of the thorn roller shall be strengthened. In order to make up for the insufficient combing degree after the speed reduction of the thorn roller, the thorn roller rack with thin teeth and large tooth density can be used. The reverse teeth on the thorn roller must be repaired in time, and the dust suction port on the machine shall be kept with sufficient negative pressure. Cleaning shall be strengthened during operation to prevent short hair from being attached.

3、 Combing process

Combing is an important process to reduce yarn hairiness. It is mainly reflected in: eliminating short fibers by a large margin, improving the straightness and parallelism of fibers to the greatest extent, and providing the most effective help to reduce hairiness; therefore, combed yarn has fewer hairiness, good sliver drying and smooth yarn.

In order to reduce the lint content of sliver, it is an effective measure to increase the lint content of sliver under a certain lint rate. In addition to the status of combing equipment, the preparation process of combing is particularly important.

In the combing process, the sliver is fully combed and the fiber is straightened and parallel, so the cohesion is very poor. A little careless operation and transportation will cause sliver breakage and quality problems. In order to prevent these problems, some factories have taken many measures, such as: covering the cotton strip with a cap made of nylon silk after dropping the barrel, using talcum powder for the joint of the barring workers, strictly setting the length to prevent dropping the barrel, etc., in order to prevent the sliver from breaking, the effect is very good.

4、 Drawing process

The key point of drawing process is to optimize the drawing process and improve the fiber straightness. The number of head pre merging and total draft should be small, not large, the number of draft in the back area should be large, not small, the distance between the back areas should be large, not small; the number of merging and total draft in the second area should be large, not small, the number of draft in the back area should be small, not large, the number of draft in the front area should be large, not small, the front and back areas should implement the process idea of heavy pressure, tight separation and strong control; For pure cotton combs, the use of single and strip self leveling is of great benefit to prevent the problems of over maturity of fiber, poor cohesion, easy to break of sliver and increase of hairiness.

It is worth noting that the smoothness of drawing channel is an effective measure to reduce yarn defects and hairiness. It is very simple to do, but the key is to persist in doing well for a long time. Some factories pursue one-sided barrel capacity, fixed length is very long, which causes a lot of friction and fluffing of upper layer sliver, which seriously affects the quality. These problems must be eliminated. In addition, the quality of the sliver is poor and the static electricity is serious. There will be a layer of plush around the sliver, which will seriously affect the smoothness of the sliver. At the same time, if the height of the sliver and the position of the sliver barrel are not suitable when the sliver is unwinding, the sliver will be seriously touched and brushed, resulting in the increase of hairiness in the subsequent process. These humble jobs have a great impact on hairiness and need serious attention.

5、 Roving process

The key points to reduce hairiness in roving process should be to increase the tightness of the sliver, to improve the fiber straightness and parallelism, and to improve the roving finish. The following should be done specifically:

① It is better to master the lower drafting multiple of roving, the larger spacing of back area and the smaller drafting multiple of back area (the best control is 1.08-1.15 times of elastic drafting);

② Under the premise of satisfying the spinning normal draft, the roving twist coefficient is larger, which is beneficial to reduce hairiness;

③ Roving adopts four roller draft with finishing area, which is beneficial to reduce hairiness;

④ It is beneficial to reduce the hairiness by using the appropriate front and back area cotton collectors with proper openings and false twisters;

⑤ Properly increasing the moisture regain of roving (6.5% - 7.5%) is beneficial to reduce hairiness;

⑥ Proper storage and transportation of roving can reduce the hairiness.