Spun Polyester

How to choose the suitable cot apron according to the type of slub yarn?

Slub yarn is a new type of fancy yarn popular in recent years. Its quality directly affects the weaving efficiency and fabric style of the later process. Cots and aprons are the main equipment of spinning drafting, which play an important role in yarn quality, especially when the level of raw materials and equipment changes little.

For the spinning of slub yarn, the function of cots and aprons can not be ignored. Although there are large and small slubs on slub yarn, the reflection of yarn slightly uneven is not obvious, but the yarn line dry difference will affect the definition of slub on cloth, and the three-dimensional concave convex effect and level sense of slub yarn are not obvious, thus affecting the style of cloth. Moreover, the other quality requirements of slub yarn are not lower than that of ordinary yarn. Because of the existence of a large number of slubs, the single yarn breaking strength decreases, the strength CV value increases, the hairiness increases, and even the "big belly slub" with the slub coarseness much larger than the standard slub coarseness appears. Therefore, the breaking rate is relatively high in the spinning and weaving process, and even affects the fabric appearance.

If the cots and aprons can be used reasonably when spinning slub yarn, it can not only improve the sliver dry and strength of slub yarn, reduce the CV value of the strength, reduce the hairiness, reduce the broken ends, reduce the appearance of "big belly slub", but also reduce the cost and improve the efficiency.

How to choose cot apron reasonably?

There are many kinds of slub yarn fiber, and the common spinning varieties include pure cotton slub yarn, hemp cotton slub yarn, polyester cotton slub yarn, pure polyester slub yarn, polyester viscose slub yarn, etc. Different types of fiber require different cots and aprons.

Pure cotton slub yarn

Cotton slub yarn is generally used to weave denim or medium and high-grade clothing fabrics. We spin c14.6 tex slub yarn with double-layer cots of shore A65 degree and shore A70 degree respectively, and do a lot of comparative tests on the same spindle. See Table 1 for the test data.

It can be seen from the data in Table 1 that the yarn spun with shore A65 degree cots has high breaking strength, small strength CV value and less hairiness; therefore, the cots with low hardness and good elasticity should be selected for spinning pure cotton slub yarn, especially pure cotton fine and special slub yarn. The lower the hardness of the cot, the better the elasticity. Under the pressure, the width of the gripping jaw composed of the cot and the roller shortens the length of the floating area and the length of the twisting triangle area, which is beneficial to the sliver drying and hairiness reduction. Moreover, the horizontal gripping is even, and the edge fiber of the whisker has strong control ability, which is conducive to the reduction of fiber loss, so as to improve the yarn strength and reduce the strength CV value. If we choose aluminum liner cots, the quality will be better, but we need surface micro treatment to reduce the wound and broken ends.

In addition, we have also made comparative tests on the diameter of cots, the hardness of aprons, and the inner patterned aprons and the flat aprons. The test results show that the yarn quality has been improved to some extent by using the large diameter cots, the low hardness aprons and the inner patterned aprons, but the degree of improvement is smaller.

Generally speaking, when spinning pure cotton slub yarn, the cot diameter is 29 mm-30 mm, the shore a hardness is 60-70 degrees, and the top apron shore a hardness is 60-65 degrees.

Ramie cotton blended slub yarn

Hemp cotton blended slub yarn is generally used to make clothing fabrics or bed textiles. We spin hemp cotton 58.3 tex slub yarn. Because the length of hemp fiber is very poor, the length is more than 100 mm, and the length is only 10 mm. It is not easy to draft with normal draft, and it is easy to get out of hard head, so we use slippery draft, but there are many broken ends. Through analysis, most of the broken ends are "little mice" with short fibers gathered, that is, the short fibers are not effectively controlled in the drafting process System. We have reduced the front and rear roller spacing and the draft multiple of the rear area to the minimum, and the jaw spacing is also too small to grasp. We have made a comparative test on the spinning frame with different diameter cots of shore A68 degree and shore A75 degree respectively, and measured the break of the head when the spindle is 1000. it can be seen that the hardness of COTS is low and the number of broken ends is small; the diameter of COTS is large and the number of broken ends is small. Because of the use of large diameter, low hardness cots spinning, the short fiber has been better controlled, at the same time, the width of the grip jaw line has been increased, the length of the floating area has been reduced, the longer hemp fiber can be stretched out through the slide draft, and the roving will not be lowered; the shorter hemp fiber can also be effectively controlled, so the yarn breakage is greatly reduced.

Generally, the diameter of COTS is 29.5mm-30.0mm, the hardness of Shore A is 68-70 degrees, and the hardness of Shore A is 65 degrees.

Polyester cotton blended slub yarn

Polyester cotton blended slub yarn is generally used for weaving medium and high-grade clothing fabrics with high quality requirements. However, polyester fiber has a large tractive force in the process of drawing, so it is not easy to draw out the "big belly slub", so the pressure should be increased to enhance the grip. If the hardness of cots and aprons is too small, they are easy to deform under high pressure, and are easily damaged by polyester fiber's greater traction, which is more serious for polyester cotton slub yarn with large number.

By testing the CV value and hairiness of yarn strength for many times, and checking the damage degree of cot surface, we conclude that: when spinning polyester cotton blended slub yarn, the hardness of cot Shore A is generally about 70 degrees, the diameter is 29.5mm-30.0mm, and the hardness of upper apron Shore A is 65 degrees. The CV value of yarn strength is relatively small, the hairiness is relatively small, the "big belly slub" is less, and the yarn quality is obtained The utility model can ensure that the requirements of the users are met and the service life of the cot is prolonged. When the yarn number is large,