The uneven twisting of double-twisted yarn often occurs in the first few or last few bobbins at the front or back of the loom. This is caused by the loose dragon strap and the tight edge. As for other cases of uneven twisting,
One is to check if there are any foreign objects stuck on the spindle wheels.
Second, check if there are any accumulated fibers in the brake.
Thirdly, check if there is any accumulated flower matter on the spindle plate.
Fourth, check whether the pneumatic braking valve is properly integrated with the spindle wheel.
The fifth reason is that the tension wheel is damaged and does not function properly, which leads to uneven twist in some of the spinning units.
When reducing the unevenness of twisting in a twisting machine, the following points should be noted:
1. Ensure that the tension of the dragon belt is moderate.
2. Remove the accumulated fibers from the bottom of the spindle promptly.
3. If the dragon belt gets worn out, it should be replaced immediately.
4. Conduct regular monitoring of the spinning speed and incorporate it into the cycle management system. For slow-spinning spindles, they should be promptly repaired or replaced.
5. Ensure the consistency of tube quality and reduce uneven twisting caused by tube quality issues.
6. Try to avoid using plastic pipes. Plastic pipes have a lower friction coefficient, which causes the flow to be out of sync and result in strong swirling.
7. Ensure that the machine and yarn channels are thoroughly cleaned.
The following are the parts of the doubling machine that need to be inspected frequently:
The spindle section
Check the flexibility of the spindle operation: ①. Remove the spindle; ②. Grasp the stationary disc and gently rotate the rotating disc to check if the rotation is smooth? Are there any abnormal sounds? Is there any lack of oil?
If any abnormal spindles are found, handle them in the following sequence:
With force, pull out the stationary disc (the filament binder) to separate it from the wire disc.
② Check if there are any waste fibers wrapped around the spindle bearings. If so, remove them and inspect the flexibility of the bearings.
③ There is no yarn entanglement, but the bearing does not rotate smoothly; or even after removing the yarn, the bearing still does not rotate smoothly. In such cases, a special fixture should be used to remove the bearing and replace it with a new one.
④ Use a special fixture to hold the inner ring of the bearing, and then press the bearing in.
⑤ After re-putting the ring on the bearing, the stationary disc is pushed in.
If there is insufficient oil at the end of the shaft, it should be refilled immediately.
2. Dragon Belt Section
Check if the dragon belt is making abnormal sounds, if it is moving up and down, if it is tangled with yarn, and if it is沾 with oil. Abnormal sounds from the dragon belt indicate that its operation has gone awry, or that it has wrapped around the yarn. Check if the dragon belt has touched the lowest part of the guide. If it has, adjust the height of the tensioning pulley. Start the adjustment from the side of the driving pulley. When right-twisted, the dragon belt rotates clockwise, so start the inspection from the driving pulley and check clockwise for one full turn. If the dragon belt is tangled with yarn, handle it when the machine is stopped if there is only a small amount of yarn. If there is a large amount, it needs to be dealt with immediately. Otherwise, the dragon belt will slip and make abnormal sounds. When the dragon belt is severely contaminated, the spindle speed will decrease, the dragon belt will slip, and abnormal sounds will occur. Therefore, remove the dragon belt and clean it with neutral detergent.
3. Tightening the guide wheels
During the dragon belt drive, the tension of the dragon belt is maintained through the outer side of the tensioning pulley and the inner side of the dragon belt. The main function of the tensioning pulley is to keep the tension of the dragon belt and ensure that the transmission does not slip. When adjusting the tensioning pulley, it is necessary to ensure that the rotation of the tensioning pulley is flexible. If the rotation of the tensioning pulley is not flexible, it will wear the dragon belt. At the same time, it is necessary to ensure that the transmission of the tensioning pulley is smooth. If the dragon belt is too high at this time, it needs to be adjusted downward. The steps are as follows: ① Loosen the tightening screws; ② Loosen the left lifting screws and then unscrew the right lifting screw; ③ Tighten the tightening screws. Generally, the adjustment range of the dragon belt is very small, and it is advisable to make the position of the dragon belt on each tensioning pulley the same.