After spinning, the drafting drive shaft breaks causing […]
After spinning, the drafting drive shaft breaks causing the fineness variation
Yarn defect form
The transmission shaft of the middle and rear rollers of the FA series spinning frame is long, and the transmission load is too large, and it is easy to break, and it is not easy to find after the break. The yarn has a serious deviation during detection, and the serious one can be determined as degradation. In actual production, the variation of 14.6 tex yarn is 17 tex, 18.2 tex variation is 19.5 tex, 22.4 tex variation is 24.6 tex, etc., flowing into the subsequent process will cause a large area of cloth. Issues such as crossover and uneven dyeing.
Analysis of yarn defect formation mechanism
The rear roller drive is responsible for the buffering and decomposing of the spinning draft distribution. Rear roller drafting is an important support point to improve the drafting ability of the front zone. The main function of drafting in the rear zone is to prepare for the front zone, so that the yarn fed to the front zone has a uniform structure and tightness, while ensuring the distribution of friction in the front zone, forming a stable draft zone to give full play to the apron control The function of fiber movement achieves the purpose of reducing thick knots and improving the appearance quality of the cloth surface. When the rear zone roller loses the active control of the original draft ratio, it becomes pulled by the inertial force generated by the collective feeding of the yarns, and the draft ratio at this time is reduced. The total draft is the product of the sub-draft multiples. The change of the post-draft multiple causes the change of the total draft. The decrease of the post-draft multiple causes the decrease of the total draft multiple and the increase of the yarn weight.
Causes and prevention of yarn defects
(1) After the rear roller breaks, the front roller drives normally, and the rear roller continues to drive through the roving yarn strip, but the drafting ratio has been out of control, resulting in yarn fineness variation;
(2) The equipment is out of repair, the overhaul period is too long, the drive shaft is not replaced in time, and the fatigue runs;
(3) The position of the front wall panel is twisted;
(4) The test period is too long.
(1) When the equipment is flat mounted, the entry and exit distances of the front wall and the pagoda must be strictly calibrated. The longitudinal direction requires 11±0.50 mm, and the transverse direction is corrected with a special tool. The 0.10 mm micrometer is taken as the standard; the center line of the wall panel Must be controlled within a tolerance of 0.30 mm;
(2) Regardless of the size of the variety, ensure the quantitative deviation of the daily test;
(3) Strictly fix the supply to prevent problems and expand the tracking range and reduce losses;
(4) Replace the drive shaft in 5-6 years to prevent fatigue operation;
(5) Paint color marks on the rear roller and check it regularly.
The main reason for spinning equipment factors to produce yarn defects is that they are usually not repaired and maintained in time. To prevent yarn defects caused by equipment factors, a strict maintenance system should be adopted. The maintenance standards are based on the implementation of the process requirements of each department. By taking measures, the yarn defects caused by equipment factors can be reduced within a certain range and the product quality can be continuously improved.