1: Weft breakage

(1) Mechanical aspects 1: Yarn tip entanglement or curved weft breakage

The weft yarn tip on the right side of the fabric At this point, there is a slight tangle or bend, forming a short weft and causing a stop.

A: Reasons

(1) The opening is unclear due to loosening of the edge yarn, twisted edge yarn, false edge yarn, warp yarn defects, flying flowers, etc. on the right side of the fabric. .

(2) The main nozzle pressure is too high, or the installation is not standard.

(3) The main nozzle injection time and the electromagnetic needle action time are not coordinated properly.

(4) The height and position of the electromagnetic needle are not standard.

(5) The compressed air pipeline is leaking.

(6) The auxiliary nozzle pressure is too low, and the height and angle are inappropriate.

(7) The scissors on the left side are not sharp.

(8) The warp yarn on the left side of the selvedge is loose.

(9) The reed surface is not clean, with flying flowers and debris attached.

(10) The solenoid valve is not working properly.

B: Elimination method

(1) Increase the warp tension or remove yarn defects and fly adhesion.

(2) Reduce the main nozzle pressure or adjust the main nozzle pressure position.

(3) Advance or delay the development time of the electromagnetic needle, and advance or delay the main nozzle injection time to an appropriate time.

(4) Check according to timing standards and installation specifications, and adjust the electromagnetic needle.

(5) Regularly inspect compressed air pipelines.

(6) Increase the auxiliary nozzle pressure and check its height and angle (depending on the type of weft yarn). (7) The scissor blade on the left side must always be kept sharp.

(8) The threading method of the twisted edge warp yarns in the healds and reeds must be correct.

(9) Always keep the special-shaped reed surface clean.

(10) Press the test button on the control panel. If the solenoid valve is found to have stopped working, check the solenoid valve. If the solenoid valve works but does not work during continuous operation, check the encoder.

2: Weft bending type broken weft

The U-shaped bending of the weft is caused by insufficient weft insertion, poor shedding and delayed arrival of the weft. This will cause the loom to stop or form double thin weft defects.

A: Reasons

(1) The injection time of the main nozzle and the action time of the electromagnetic needle are improper.

(2) During shearing, the weft yarn comes out of the electromagnetic needle.

(3) The compressed air pipeline is leaking.

(4) The auxiliary nozzle pressure is too low.

(5) The shedding of the loom is faulty, and the warp yarn has hairiness, big knots, flying flowers and other yarn defects.

(6) The opening amount is too small or the opening time is not standard.

(7) The warp yarn hits the tip of the auxiliary nozzle.

(8) The warp tension is too small.

(9) The position of the main nozzle is incorrect.

B: Elimination method

(1) Advance or delay the opening time of the electromagnetic needle, and advance or delay the injection time of the main nozzle.

(2) Adjust the action time of the left scissors and yarn guide to reduce the cutting resistance; or increase the shear blowing pressure appropriately.

(3) Check for bent or leaking mechanical valves and air pipes, and adjust or replace them.

(4) Properly increase the auxiliary nozzle pressure.

(5) Strictly control the warp joints to be less than 3mm, and remove warp defects such as large joints, feather yarns and flying flowers.

(6) Increase the opening amount, check and adjust the opening time.

(7) Move the auxiliary nozzle laterally by 0.1~0.2m, and check the smoothness of the head end of the auxiliary nozzle.

(8) Measure and increase the warp tension. (9) Use the main nozzle gauge to correctly adjust its position.

3: Weft breakage caused by the weft getting entangled with the warp on the left side of the selvage

The shedding time does not match the weft flying time properly, and the weft gets entangled by the warp on the left side of the weaving. Stops or weft defects occur.

A: Reasons

(1) The electromagnetic needle time, the main nozzle yarn spraying time and the opening time are not coordinated properly.

(2) The twisted yarn on the left side of the fabric is loose or the other edge warp yarns are loose.

(3) The main nozzle is not installed correctly.

B: Elimination method (1) Delay the time when the weft yarn breaks away from the electromagnetic needle and advance the opening time.

(2) Correct the tension of the twisted edge yarn and false edge yarn, or correct the opening time.

(3) Use the main nozzle gauge for correct adjustment.

4: The weft yarn and warp yarn are twisted and broken.

The weft yarn and the middle warp yarn are twisted, forming an S-shaped bend. Mainly due to uneven warp tension in the warp sheet or yarn defects attached to the warp yarn, shedding faults may cause the loom to stop or form double deweft defects.

A: Reasons

(1) The warp yarn tension is too small or the sheet yarn tension is seriously uneven.

(2) Warp yarn defects (many feathers, large knots, neps, cotton balls, flying flowers attached, etc.).

(3) The opening is too small.

(4) The left scissors cut the yarn poorly.

B: Elimination method

(1) Measure and increase the warp tension to eliminate factors such as uneven local tension.

(2) Remove yarn defects and splice tail yarn no more than 3mm.

(3) Increase the opening height appropriately.

(4) Adjust the left scissor action time and blade engagement amount to make the scissors sharp.

5: Weft breakage caused by uneven weft insertion length

The length of the weft yarn introduced into the fabric fell is of different lengths, resulting in the phenomenon of long and short wefts. It is mainly caused by unstable length measurement and weft insertion and insufficient weft insertion force.

A: Reasons

(1) Insufficient pre-winding amount of weft yarn.

(2) The closing time of the electromagnetic needle is too early.

(3) The main nozzle is blocked by cotton yarn and the pressure is too low.

(4) The weft winding shape is poor or the winding hardness is inappropriate. The quality of the weft yarn is poor, and there are many yarn defects, such as splices, flying lint and yarn waste.

B: Elimination method

(1) Remove flying flowers and check the jet airflow.

(2) Wind the yarn correctly again.

(3) Adjust the pressure according to prescribed methods and standards.

(4) Appropriately increase the prewinding amount of the weft feeder.

(5) Delay the closing time of the electromagnetic needle.

(6) Increase the main nozzle pressure.

(7) Remove the lint clogging the parts.

(8) Change the form of weft winding, improve the hardness of the weft tube, greatly improve the quality of weft and reduce yarn defects.

6: Yarn tip blow-off type weft breakage

It is mainly caused by the air jet pressure of weft insertion being too high or the weft yarn having weak knots.

A: Cause

(1) The main nozzle pressure is too high.

(2) The shear blowing is too strong.

(3) The weft yarn is uneven and the yarn body has many details.

B: Elimination method

(1) Reduce the main nozzle pressure.

(2) Reduce the shear blowing pressure.

(3) Replace the weft yarn and take measures to improve the quality of the weft yarn.

7: Weft breakage caused by blowing in the middle of the weft yarn

The weft insertion force is too strong, the action time is too long, or the details of the weft yarn are blown off within the width of the fabric, causing the loom to produce Stop or form double thin spots.

A: Cause

(1) The release angle of the weft yarn is too small.

(2) The pressure of the main and auxiliary nozzles is too high, the opening (start and end time) is too large, and the injection angle of the auxiliary nozzles is too large.

(3) The weft yarn has weak details.

B: Elimination method

(1) Appropriately increase the release angle.

(2) Reduce the pressure of the main and auxiliary nozzles, check the weft yarn flight curve, reduce the opening (start and end time), avoid excessive injection, and reduce the injection angle of the auxiliary nozzle.

(3) Replace the weft yarn to improve the quality of the weft yarn.

8: Weft breakage on the weft storage side

During the weft release and stop process, it occurs because the weft insertion force is too strong or the weft has weak yarn details.

9: Shearing error type weft breakage

Shearing error type weft breakage is caused by the weft yarn on the side of the main nozzle not being cut after weft insertion but before beating up.

A: Reasons

(1) The scissor blades are sharp and poorly meshed.

(2) The scissors are poorly installed and the cutting time is not standard.

(3) The shear blowing pressure is too low.

(4) The weft yarn reaches the opposite side later.

B: Elimination method

(1) Grind the blade periodically and adjust the meshing.

(2) Correct the position and adjust the time according to the scissors installation specifications.

(3) Appropriately reduce the shear reduction blowing pressure.

(4) Increase the pressure of the main and auxiliary nozzles and extend the injection time of the auxiliary nozzles.

10: Stop by error

The weft yarn reaches normal, but due to abnormal weft yarn flight, twisted edge yarn, weft catching edge yarn, electrical failure and other reasons, no weft yarn arrival signal is mistakenly sent , resulting in shutdown:

A: Reasons

(1) The weft yarn enters the weft-catching side yarn abnormally.

(2) The yarn on the right side of the hem is loose.

(3) The shape or position of the weft yarn reaching the probe is incorrect.

(4) There is a problem with the weft probe cable, or the surface of the steel port reflection area of ??the probe is not clean.

(5) The sensitivity of the weft detection head is poor and the detection board is faulty.

(6) The gap between the weft probe and the reed is inappropriate.

(7) Vibration of special-shaped reed teeth.

B: Elimination method

(1) Adjust the position of the nozzle to remove lint and solve the problem of weft yarn slack.

(2) Adjust the edge yarn tension to make the edge yarn reed meet the specifications.

(3) Adjust the angle of the last set of auxiliary nozzles and keep the distance from the weft detection head WWF1 to about 50mm.

(4) Replace the faulty weft finder in time and keep the probe and reed clean at all times.

(5) Check the sensitivity of the weft yarn detector so that it does not shut down the vehicle empty. Also check and replace the weft probe board.

(6) Adjust the gap between the weft detection head and the reed according to the installation specifications.

(7) Sticking a black tape on the reed can not only reduce the vibration of the reed teeth, but also prevent the spread of the reed jet airflow.

Cloud weaving

11. Cause of formation: uneven density in the fabric, like cloud spots.

(1) The let-off mechanism is faulty: the rear beam is inflexible, the buffer function is poor, the stabilizing mechanism is poor, the output shaft is worn, and the tension sensor is bad.

(2) Failure of the coiling mechanism: The gear meshing of the coiling system is too tight, the teeth are too shallow, the clutch is worn, and the reed support bearing is worn, which affects the stability of the beating force.

2． Elimination methods

(1) Improve the function of the rear beam and replace worn parts.

(2) Check the zero tension and adjust it correctly.

(3) Check the coiling mechanism to keep the coiling function in good condition.

12. Double weft: There are two complete or incomplete weft yarns that merge together to destroy the crossing pattern of the fabric, which is called double weft. If there are sparse gaps (sparse gaps) between the double wefts, it is a broken weft.

Causes:

(1) The opening is unclear. When the weft yarn enters the shed, the warp yarns on the entrance side or other areas are loose and adhered, and the weft yarn head end will be hung to form a double weft. .

(2) The installation position of the left scissors is poor or high or low, the weft yarn is cut continuously or the scissors are not sharp.

(3) After the weft was broken, the weft finder misjudged or was poorly adjusted, and the machine was not turned off.

(4) Poor operation, the bad weft that should be taken out was not taken out.

2． Elimination method

(1) Adjust the shed or delay the opening time to meet the requirements of the weaving process, and increase the tension appropriately.

(2) Pay attention to the installation position of the scissors and keep the blades sharp.

(3) Correctly adjust the weft finder gain to achieve the best condition.

(4) Strengthen operation management.

(5) Determine the appropriate speed according to the yarn count.

13. Weft loss: The cause of excess weft yarn brought into the fabric, both in the same shed, is called weft loss.

1. Causes

(1) The weft stop pin is not working properly and the entry-side scissors are not cutting the yarn properly.

(2) The weft detector works poorly.

(3) The normal spray and shear spray pressures are poorly matched.

2． Elimination method

(1) Correctly adjust the weft stop pin and left scissors, otherwise replace them.

(2) Install and adjust the weft finder correctly.

(3) Adjust the pressure and time of normal spraying and shearing spraying.

14. Open edge: The twisted edge yarn cannot twist the weft yarn, making the edge weft yarn structure loose.

1. Reasons

(1) Poor selection of selvage yarn.

(2) The automatic stop of the selvage yarn ends fails.

(3) Mechanical failure of the hemming device, poor performance after wear and tear, and abnormal opening.

(4) The yarn tension at the twisted edges is inconsistent, and the twisted edges are not firm or cannot be twisted.

2． Elimination method

(1) Select the appropriate hank yarn.

(2) Check the automatic stopping device of the hemming machine to keep it sensitive.

(3) Strengthen maintenance and repairs to ensure normal operation.

(4) Adjust the tension of the twisted yarn to keep it consistent.

15. Temple defects: 1-3 warp and weft yarns of the fabric located at the temples are cut off.

1. Causes

(1 ) The side bracing or edge bracing position is too high or too low, the fabric fell is not at the same level, the cloth body is vibrated by the beating force during beat-up, and the fabric in the edge bracing is held by the licker-in roller and stretch and cannot move, resulting in shear force.

(2) The cloth surface tension is too large.

(3) The cloth surface leaves the licker-in and loses the stretching effect.

(4) The side brace is slow to prick, and the needle is broken or bent.

(5) There are debris in the prick ring, and the rotation is not flexible.

(6) ) The temperature and humidity in the workshop fluctuate greatly.

2. Elimination method: In order to prevent and eliminate temple brace defects, the stretching effect of the temple brace should be brought into play, the needle tip of the thorn ring should be kept in good condition, the rotation should be flexible, and the temperature and humidity fluctuations in the workshop should be small. .

(1) The side brace thorns and rings are well matched and well installed; select the appropriate thorn rings, row number and thickness according to the variety.

(2) Keep the thorn rings flexible in rotation , to ensure that the needle is continuous and does not bend.

(3) Make sure that the thorn ring does not move left and right on the core of the licker-in.

(4) The relevant parts of the loom are normal, and the temperature and humidity are normal. .

(5) Pay attention to the knotting operation of the upper shaft, check the thorn ring, remove flying debris and waste wire, and install the temple supports strictly according to the operating standards.

II. Weft shrinkage: The weft yarn is woven into the fabric with twists or loops on the cloth surface.

1. Cause: The weft shrinkage is greater than the airflow injection pressure and the injection time.

(1) When the air pressure is low, the flying speed of the weft yarn is slow, unstable, and the tension is small. In addition, the movement of the reed and heald will simultaneously affect the flying of the weft yarn and cause the weft shrinkage.

(2) Injection time Improper cooperation causes the weft yarn to fly in a loose state.

(3) Poor timing of the scissors on the entry side causes weft shrinkage.

(4) The weft yarn has a large twist and is unstable, twisting back The rebound is too large.

(5) The winding force of the weft yarn on the weft feeder is uneven, and the yarn blocking pin and the injection time are poorly coordinated.

2. Elimination method

(1) Increase the injection pressure appropriately, gradually increase the pressure difference by 0.01--0.02, and adjust until the weft arrives within the set time.

(2) Adjust each nozzle according to the actual arrival time of the weft The injection time.

(3) Adjust the entry side scissors time to ensure that the scissors are intact.

(4) Improve the weft quality.

(5) Check the storage Check whether the operating function of the weft device is good and eliminate hidden dangers.