How to deal with quality problems in spinning?(5/6)
5 average strength and strong weak ring
Some quality problems in spinning, such as hairiness, nep, different fiber, strong weak ring and immature fiber content percentage, are all important problems that directly affect yarn quality, fabric quality and production efficiency of downstream processes. We should attach great importance to them, fortify them one by one, and use various high-tech testing instruments to monitor and solve the above problems online and offline, at least can do so To find problems in time and take measures to reduce the quality problems found. In order to further improve the spinning quality.
(1) the strength characteristics of the original yarn include average strength, strength unevenness, average elongation and elongation unevenness. Generally, the average strength of warp yarn is 15 CN / tex, the strength unevenness is about 9% - 10%, the average strength of weft yarn is 12 CN / tex, and the strength unevenness is about 9% - 10%. The average elongation at break is generally controlled within 2%.
(2) the important strength index of air-jet loom stop is the strong weak ring, i.e. the minimum strength. It is generally believed that when the yarn fineness is only 40% of the normal yarn, the weak ring in this detail will inevitably lead to end breakage and stop. If the strong weak ring is at 4cn / tex and the elongation is lower than 2%, it will inevitably lead to end breakage.
(3) in addition to 61% of other strong weak rings, other weak twists, poor joints, including miscellaneous thick joints, etc. will also cause stoppage between warp and weft, accounting for about 39%.
(4) in addition to the average strength and uneven strength, the strong weak ring is an important factor in the production of warp and weft yarn stop. Japanese businessmen come to China to buy Yarn, with special emphasis on the number of 100000 strong weak ring. According to the 100000 weft breakage detected by tensogiet of high-speed and large-capacity strength machine, the possibility of yarn purchase can be judged. Therefore, in a large-scale knitting and weaving factory, the strength requirements of yarn should especially emphasize the level of strength and weak ring. Some related enterprises in China should equip tensogiet strength meter as much as possible to ensure the quality of the original yarn.
(5) there are three kinds of details on the original yarn: one is the short pile detail, the other is the knot of the thick and thin knots, and the other is that the filament knots or several short details connected together will cause the breakage.
(6) in order to reduce the strong weak ring and provide good raw yarn for the downstream process, the corresponding measures must be taken, such as the new roving frame with four unit drive in the form of four roller draft, on the one hand, the details caused by the switch car are eliminated, on the other hand, the draft strip dry is improved, and the defects of the coarse details are reduced, on the other hand, the matching of the transmission teeth and keys of the draft part is strengthened, so as not to make it loose and ensure Drawing process synchronization is also one of the important methods to reduce details.
In addition, one of the factors to reduce the details is to reasonably configure the process and select good drafting components, such as cots, aprons, upper and lower pins, and pressure mechanism.
