Precautions for setting openings on air jet looms

1. How does the size of the opening affect weaving?
① The large opening amount can cause high tension on the warp yarn at the heald, which can easily cause breakage of the warp yarn;
② Increasing the opening amount can reduce the hairiness and adhesion of the warp yarn, resulting in good stretching, clear opening of the warp yarn, and reduced weft stop;
③ Increasing the opening amount leads to good weft beating performance, which is conducive to weft beating and fabric formation;
④ If the opening amount is too small, both the inlet and outlet of the weft yarn will be blocked, which can easily cause weft stoppage, weft shrinkage, shedding, double weft and other weaving defects.
2. What is the impact of the opening time on weaving?
In general, advancing the opening time can improve the poor opening of the warp yarn at the weft population and improve the style of the fabric, resulting in good weft beating. However, due to the early opening and closing of the warp yarn, the arrival time of the weft yarn is shortened, which can easily cause defects such as weft shrinkage and shedding. Therefore, it is necessary to increase the air pressure. When weaving fabrics such as 2/1 and 3/1, if the opening time is too late, There may be cloth cracks in the air guide part of the reed, which needs to be considered.
3. What should be noted when setting the opening amount?
① The opening amount should be small while meeting the requirements of weft insertion technology;
② The more the number of heald frames, the greater the difference in tension between the front and rear heald warp yarns. It is advisable to use a semi clear weave to reduce the increase in opening between heald sheets;
③ The opening amount of thin fabrics should be appropriately small, while the opening amount of thick and dense fabrics should be appropriately increased;
④ When using a large opening amount, it is necessary to appropriately reduce the warp tension; When using a small opening amount, it is necessary to increase the warp tension appropriately.