How to deal with the "three jumps" of fabric weaving machine?
First, start with the process of spinning and semi-finished products
1. Clearing and falling objects, through the adjustment of a036, a076 dust bar gauge, the falling rate from 2.57% to 4.43%; combing the falling objects, by adjusting the distance behind the car, the falling rate from 5.2% It is about 6.5%. After the adjustment, the surface of the yarn is reduced in the amount of hemp and sesame seeds, and the chance of mixing in the weaving is also reduced, which can reduce the "three jumps" drop by 20% to 30%.
2. The rapier loom has high quality requirements for the original yarn, and the smaller the long segment irregularity is, the better the requirement is. The general requirement is 3% to 4%, the dryness cv value is 20% to 25%, and the single yarn strength cv value. In 18% to 20%.
3. To improve the quality of the joint, the end length is generally 1.5mm ~ 4mm is the best, the greater the degree of joints should be particularly to prevent small dumplings.
4. Warping requirements to ensure that the "three spirits", that is, flexible rotation of the tension ring, flexible braking, automatic stop off the end of a flexible, while slightly heavier, so that the full width of warp yarn even.
5. Improve the quality of sizing, improve the clarity of the warp yarn, select a suitable size according to the variety and formulate the sizing rate. Generally, the sizing rate of 8% to 9% of the cotton can meet the surface of the warp yarn to form a smooth and wear-resistant film. To properly control the moisture regain, the relative humidity of the weaving workshop is above 80%, the sizing regain can be controlled at about 7% to 8%, and the sizing elongation can be reasonably controlled. The sizing fabric can be controlled below 1%; the reinforcing rate is in the range of About 10% to 15%, this can meet the rapier looms fabric requirements.
Second, the opening and sword time should be appropriate
Jumping yarn defects generally have more chances to be generated on the side of the sending weft sword. Therefore, different configurations can be used to adjust the weaving parameters on both sides. The time for sending the sword into the weft sword is appropriately delayed, and the time for the sword to enter the weft sword is appropriately advanced to send. Wei Jian entered a relatively clear weaving mouth.
Generally speaking, the opening time of cotton varieties should be 290°~300°, sword time 70°~75°, and when sending swords, the position of the sending weft sword should be 4~6 guide rails from the weaving mouth, and the position of the weft sword should be from the weaving mouth. ~ 4 guide rails, but also to ensure that the sword into the slow, quick sword, so that the sword with enough time through the clear Kendo, reducing the chance of jumping.
Third, the adjustment of the position line
Adjust the position line height, generally only adjust the height of the stop frame and the back beam. When the warp stop and the back beam are lifted, the warp tension difference between upper and lower layers will increase. When the weaving mouth is full, the lower warp yarns will be tight and the upper warp yarns will be loose so that the warp yarns will be evenly arranged and a more full cloth will be obtained.
If it is lifted too high, the upper warp yarns are too loose and the warp yarns stick to each other, making the opening unclear and prone to star jumping. Generally, the height of the back beam of a variety of hemp cotton is 70mm-80mm, and the height of the stop-motion frame is 30mm-40mm, and both ends must maintain the level.
Fourth, correct hoisting specifications
It is generally better to grasp the lower warps and not lower them. It is better for the sword head to enter the weaving mouth without touching the upper and lower warps. On the upper shaft and overhaul work, adjustments shall be made to the lifting hedging to ensure that the "three togethers", that is, the heald frames, the heald shafts, the step plates and the rotors. “Siping” refers to the heald frame (complex bar) flat, the helicoid bolt flat, the heald heald plate flat, and the tread rods flat.
If unqualified, it is also necessary to check whether the heald jack has come off, whether the treadle top wire is loose, whether the hoisting axle bearing pad is worn or not, whether the hanging strap is deformed or not. Generally, the front and rear positions of the hoisting shafts are about 110mm to 120mm, and the turbulence does not exceed 0.8mm, and the hoisting height is 400mm to 410mm.
In the above measures, a 8s×8s42×38 cotton/cotton plain weave experiment was conducted on a GA747 type loom, the efficiency of the loom was increased from 50% to 65%, and the “three jump” defect was reduced from 500 to 200 in the 90m cloth. These data are tracked by the platform.