Sino Textile Machinery

Cause analysis and treatment of filling stop of jet loom

1. Gas path

1.1 Air filter

Due to compressed air contains a certain amount of dust and impurities, when work must ask after jams mesh, spray cleaning not in time will cause the main and auxiliary injection pressure drop and valve core product pollution, valve core movement is not sensitive, which directly affect the effect of weft insertion, zonal stop machine. Therefore, the strainer should be cleaned regularly in time, and the more serious blockage should be replaced in time.

1.2 The main nozzle

The main effect of main jet is to overcome the weft insertion resistance. Too much pressure will affect the arrival time of the weft yarn, and the pressure is too high, which can cause the filling to stop when the main jet flow is opened in a moment. Moreover, when the main jet pressure is large, the swing of the weft end is increased in the wind tunnel, which will increase the chance of filling. The general pressure control is about 0.3 MPa, and the weft yarn can be reached accurately as the reference standard.

Varieties CJ14.5 14.5/523.5/393.5 plain. Auxiliary jet pressure 0.45 MPa, To set at 90 °. The main jet stream is either too late or too late, which can cause a weft stop. On the general as early as in the electric needle around 10 ° to open. The latest in closed around 40 °, the electricity needle opening is 60 ° ~ 80 °. The main spray breeze is too big, easy to make the weft back twist, the fiber slip, the powerful descent, in the weft insertion process blowing the weft yarn. Light breezes may escape from the main nozzle, and sometimes the weft is clipped by scissors, and the end of the weft will be shrunk to affect the next insertion. When stopping at the main nozzle, gently pick up the filling with your hands and feel a little tension. The air pressure is about 0.08 MPa.

1.3 auxiliary nozzles

The auxiliary nozzle mainly ACTS as the relay nozzle, the auxiliary pressure is small, and the weft is not easy to be pulled straight to cause the filling. If the auxiliary injection pressure is too high, the filling can be blown off after the electric needle is closed, the general auxiliary jet pressure is 0.15mpa compared to the main jet pressure, and the final jet pressure is equal to the auxiliary jet pressure. Auxiliary jet tube rupture, not flexible spray nozzle clogging, auxiliary electromagnetic valve core are likely to cause jet stream disconnect, lagging behind, resulting in the weft stop. Auxiliary spray height and Angle of deviation is too big, easy to cause the jet stream direction deviation, make the weft caused by the change flight direction.

2. Bobbin and weft feeder

The height of the parts on the bobbin rack and the improper installation Angle will increase the insertion resistance, especially the pressure of the plate spring.

The receiver electric magnetic needle of weft feeder opens and closes the time inappropriately or the gap between the electric needle and the measuring board is too large or too small, and the gap between the two is usually 1.5mm ~ 0.8mn. It is possible that the needle of electric magnetic needle is not in the center, the needle is worn, the electric needle is worn, the inner ring gasket is worn, the spring is insufficient or too strong, it can cause the wrong insertion.

3. Cut the left side

At the end of the casting, the left side shear should be cut in time to ensure the weft insertion. Shear time too early or too late not only affects the weft after shearing and tension, but also affect the next weft insertion, general shear time is about 25 °. The blade of the scissors cannot be cut off smoothly and timely. The cut time will be extended, which will directly affect the next insertion. The cutting edge of the scissors should be replaced in time. Please pay attention to the position of the scissors before and after the installation, adjust the cut time and the cut position correctly.

4. weft insertion machine

The weft insertion normally arrives, and the weft detection error causes no reason to stop, the main reason has two points.

(1) The weft probe is damaged or surface is not clean, and the weft effect should be replaced or cleaned in time. When cleaning regularly, you can clean the optical surface of the light source and the photoelectric element with anhydrous ethanol.

(2) Explore the weft detector sensitivity and detecting pulse number is undeserved, detection, can be properly lowered the left weft detector sensitivity increases, to detect pulse number is reduced, or the right agent properly weft detector sensitivity decreases, and detecting pulse increases.

5. The opening section

We used to do a survey of the juice; more than 70% of the weft stops are caused by the opening. The air jet loom belongs to the free end insertion, which leads to the swing of the weft end of the weft at the time of weft insertion, and the weft stop can be caused by a few or even a single warp opening. In order to fundamentally solve the weft stop, it must be from the opening part of the staff. There are several factors that influence the opening.

(1) Yarn quality and workshop temperature and humidity. The qualities of raw yarn and the quality of sizing, especially the feather condition have a great influence on the opening. When the relative humidity of the workshop is relatively high, the warp is wet, so that the warp is not clear.

(2) Mechanical state. Tappet CAM wear, dwell of rod wear, idler pulley wear, wire rope elongation, heddles spring tension is not enough, wring side opening time and improper installation Angle is not correct, all card off, heald frame height position is wrong, the reed deformation or damaged burr defects, auxiliary nozzle yarn. Can contribute to an opening is not clear.

(3) Weaving craft. Weaving technology on the impact of opening more apparent, in order to make the weft insertion with a relatively clear shed, can increase the warp tension, increase the opening stroke, opening time, weft insertion time delay, and increasing let-off amount in advance, reduce the shed at the back of the depth and reduce the lower warp differences, to reduce the speed.

When choosing or adjusting the process, to comprehensively consider the characteristics of the fabric varieties and its requirement for process, the original yarn and the quality of semi-finished products, the conditions of the machinery itself factors, such as to minimize the other negative effects, especially warp end-breakage, must not attend.


6. Summary


We should carefully observe the position and shape of the filling in the weft, so as to help us to find the cause of the weft stop, and then take measures to the destination. In conclusion, as long as the quality of the original yarn and the quality of the yarn are guaranteed, the weaving technology shall be selected reasonably and the equipment management shall be further strengthened.