Problems and causes that easily occur during the use of paper forming fabrics

- Sep 15, 2020-

Problems and causes that easily occur during the use of paper machine forming fabrics

1. Too fast fomring screen edge wear: The most severe wear of most paper machines is at the joints with and without vacuum (the position of the paper machine forming fabric edge is 10-15cm); solutions: 1. Increase the opening of the vacuum box as much as possible. Staggered width. 2. Add normal pressure lubricating water to the edge of the vacuum box. 3. Add stiffeners at appropriate positions. 4. Check whether there are edges or gaps in the side wiper and vacuum box. Especially the joints of the ceramic panels are weak links. 5. Check whether the edges of each roll are severely worn (the diameter becomes smaller after wear, so that the tension of the forming wire mesh is smaller than the normal forming fabrics surface and further accelerates wear) 2.       The overall wear is too fast: 1, The panel quality is not good. 2. The net tension is too small, the return tension of the single-layer net is 3-4kg/cm, and the return tension of the two-layer net is 5-6kg/cm. 3. Poor packing quality. 4. The net has a large air permeability and there is a lot of filler loss, and there are too many filler particles between the paper machine forming fabrics and the vacuum box panel, and the overall wear of the forming screen will be faster. 5. The forming fabric mesh air permeability is small and the water filtration is slow, but the vacuum degree increases and the wear is accelerated. 6. The speed of the guide roller is not synchronized with the wire speed. 7. The speed of the upper and lower network is not synchronized.   Third,       Local longitudinal through-length and rapid wear: Whether there are stubbles, unevenness and nicks on the forming plate, wiper board, and vacuum box panel; whether the rollers are locally worn and rusted.   Fourth,       Partially longitudinally long drum: Whether the forming board, wiper board, vacuum box panel is stubble or uneven, whether the breast roll vacuum roll has bumps such as solder joints, and whether the rubber roll has impurities. 5.       Guide roll wrapping: the cleaning water pressure is low, the inner fiber of the net is too much; the net air permeability is low; the cleaning method is problematic. The two and a half layers of the paper machine forming fabrics should be cleaned on the paper outlet surface of the screen. Whether the nozzle is clogged, the best distance between the nozzle and the fabric surface is 15 -20cm.   Six.       Vacuum box top slurry: the air permeability of the paper machine forming fabric is inappropriate, the slurry fiber is short and the loss is large, the quality of the retention aid is not good or the addition amount is small.          The forming screen movement is large when the fabric is running: the corrector is not working properly, and the forming fabric edge is not straight.   8.      The paper machine making forming fabric becomes narrow after a period of use: local wear of the forming plate, wiper board, vacuum box panel or guide roller causes the net to run for a period of time and the marking line becomes slanted (partially inconsistent operation of the net).   Nine,      D-type device and the previous net life comparison: the D-type device can effectively solve the two-sided difference of paper, speed up the dehydration and increase the speed, but the life of the forming fabrics will be reduced. The main reason is that the water line becomes shorter and the wear is accelerated. The life expectancy is generally reduced by 1/3 or even 1/2.