There are many reasons leading to hard head, but the basic reason is that the stretching force is greater than the holding force in the process of drawing. Temperature and humidity, raw materials, operation cleaning and process, I would like to briefly talk about the reasons for common hard ends on spinning equipment based on years of experience in installation, commissioning, and patrol maintenance, so as to help readers (especially equipment maintenance personnel in the first line of spinning process).
I have always attached great importance to the importance of temperature and humidity control in the spinning process
1、 Temperature and humidity: the temperature and humidity change sharply, with large regional differences, especially the side car compact spinning machine table, long-time parking (low temperature, high humidity, cots and aprons hard and stiff), excessive water on the ground, etc.
2、 Process: (1) roving twist factor is too large; (2) roving weight is too heavy; (3) roving moisture regain is too high; (4) spinning back area spacing is too small; (5) spinning back area draft ratio is too small; (6) jaw spacing is too small.
3、 Raw materials: according to the number of raw cotton fiber changes, fiber quality length lengthened, good uniformity.
4、 Operation cleaning: especially semi-finished roving is more likely to fluctuate. Such as roving small slub, short roving and other defects, drawing roving joint unqualified.
5、 There are many reasons in terms of equipment, which are listed as follows:
1. Cradle aging, damage, too little pressure (spring aging or air leakage of airbag system).
2. Cradle pin out: air shake the front clamp shaft and spring cradle rear clamp shaft.
3. The screw of cradle shaft is loose, and the screw of air bag cover is shaken.
4. The fixed position of cradle shaft and roller seat is broken (the force of cradle is too large when pressurized).
5. The shocka spring on the cradle is aging, the gap is large, and the upper bracket moves back and forth.
6. The cot hardness is too high, the diameter is too small, the coating thickness is too thin, the concave damage, the coating is too thick and too thin, and the coating is improper.
7. The apron is too thick and hard, the inner diameter is too small, there is oil stain on the surface, and the surface is seriously concave or deformed. When the upper and lower aprons are used at the same time, the aprons are damaged, the upper and lower aprons are uneven, and the lower aprons are too partial to be apron free.
8. The bearing of the iron roller is seriously worn, lack of oil and rust, and there are accumulated flowers between the small skin rings of the iron roller.
9. Improper position of front and rear cots, too small or too large effective pressure. The front top roller inclines forward too much, and the position of the top roller after V-type draft is over.
10. The screw of rear roller slide seat is loose, and the holding force of rear roller clamp is small.
11. Improper position of the upper bracket: after that, press down the apron; before passing, rub and support the front rubber roller, and grind the front roller for the epithelial ring.
12. The upper Xiao Ka spring is lack, and the upper Xiao Ka spring is aged and the pressure is too small.
13. The upper lug of carbon fiber is damaged or the metal is deformed.
14. The pressure divider of compact spinning was damaged and broken due to excessive pressure on cradle.
15. The pressure bar is deformed and the spacer block is not up to the pressure bar, so it must be run on the pressure bar.
16. Improper pressure of guide roller of compact spinning.
17. The motion range of spinning guide is too large and deviated.
18. The upper part of the lower part is in the wrong position, and the end of the lower plate is not placed in place, and the roller bearing is pressed.
19. Large tension frame winding roving or flying flowers.
20. Improper positioning of adjusting disc of large tension support shaft.
21. The traverse device fails or the range is too small, and the roller is worn and concave.
22. Back roller with flowers and roving.
23. The gear of rear roller head is not meshed well.
24. The back roller is pulled off.
