In order to effectively meet customer requirements and control quality costs, textile mills must find the causes of these defects in the spinning production process, and take effective measures to control and reduce defects, thereby improving yarn quality.

Thick sections, details

cause

The length of common thick sections on the cloth surface varies: 1 cm～2 cm are mostly, the thicker ends in the middle are tapered, most of which are poor drafting of the spun yarn, free flying flowers attached around the drafting zone, uneven roving slivers, and roving defects attached. , It is caused by improper setting of winding clearing parameters; a small part of it is caused by poor spun yarn splicing or poor splicing of the winder. The details are mainly caused by poor yarn drafting and poor winding splicing.

solution

For thick knots and details caused by poor drafting of the spun yarn, it can be prevented and solved from the following 4 aspects:

1) Reduce the roving twist, that is, try to use a small roving twist without increasing the end break;

2) Ensure that the spinning and roving drafting elements are in good condition, maintain a proper rubber roller grinding cycle and apron replacement cycle, and check whether there are grooves, scratches and other problems at any time, and solve them at any time;

3) Maintain a constant temperature and humidity to avoid short-term and large fluctuations;

4) Optimize the spinning process, mainly the consistency of the gauge, the position of the upper pin and the pressure of the cradle. The thick knots and details produced in the spinning process can only be removed by the winding clearer, which will cause the increase in the number of cuts of the clearer. Special attention should be paid to the quality of the splicing to avoid the secondary formation of thick splicing due to poor splicing. Sections and details.

Uneven dryness

cause

The cloth surface presents regular or irregular even shadows; it is mainly caused by abnormal operation of drafting elements (cots, aprons, rollers), rough surface irregularities, cot entanglement spinning and backward spindles, etc. .

solution

1) Optimize the process of the drafting zone and maintain a good state of the rubber roller and apron;

2) Control the number deviation and evenness of the single and roving, and isolate it in time if abnormalities are found;

3) Repair the broken and abnormal spindles of the spun yarn in time, and require the turner to report abnormal situations such as rubber rollers, aprons, rollers, etc., and notify relevant personnel for handling;

4) Set the number variation and bead chain yarn defect cutting and alarm parameters for the yarn clearer on the winder, which can cut out the defects and reject the problematic bobbins.

Fly flower

cause

In the spinning production, due to untimely cleaning, cotton collecting device failure, sharp increase in end breakage, abnormal temperature and humidity of air conditioner, or poor airflow, etc., the flying flowers on the machine, the ground and the air increase and accumulate, and they are attached to the yarn during spinning. Flying defects are formed in the body. In addition, improper cleaning operations in each process will also cause the cleaning flowers to be attached to the yarn body.

solution

1) The cleaning cycle must be specified according to the cleanliness of the workshop, and strict inspections must be arranged;

2) Regular maintenance and inspection of all kinds of cotton collection devices are the same as normal spinning equipment to avoid accidental failures;

3) Do a good job in the speed inspection of the spun yarn, and control the use cycle of the ring and traveler to avoid the phenomenon of a sharp increase in broken ends;

4) Air-conditioning personnel strengthen patrol and control to keep the temperature and humidity stable, and to ensure the unobstructed air flow in the workshop;

5) The fly defect that has been formed before the winding process can be removed by the yarn clearer, but the clearing process parameters need to be adjusted, and the relationship between the number of cuts and the quality should be balanced;

6) Regulate the specific operation of the yarn channel cleaning for the stopper to avoid the cleaning flower from being attached to the yarn body during the cleaning process.

Neps

cause

Normal fibers, immature fibers, cotton seed husks are considered as neps due to improper handling during ginning or spinning, and round, flat, large or small fine particles or fiber-bearing seed scraps formed by agglomeration. Mainly due to the unreasonable raw cotton blending, bad card clothing on the card or the regrind cycle, poor condition of the combing machine, poor smoothness of the spinning channel in each process, mismatch of the process and speed of the spinning process, and the operation of the turning worker Improper, abnormal temperature and humidity, etc.

solution

1) Use cotton with low impurity content, good rolling work and low immature fiber content, use good card clothing and lower speed for carding, use dense-tooth cylinder and top comb for combing, and use pressure bar gauge for fine yarn At the same time, each process strengthens cleaning, these are the effective methods to reduce neps at present.

2) From the perspective of quality control, pay attention to the neps test results from raw cotton to yarn in production, rationally configure various processes, and regularly wipe the main spinning channels to keep the quality of raw cotton to semi-finished products and finished products under control. .

Abnormal defect

cause

Abnormal defects include the appearance of three-ply yarn, four-ply yarn, long details, and long thick knots on the fabric surface. It is more common in long fragments of double yarn, three-ply yarn and four-ply yarn. Most of them are caused by yarn breakage in the winding, doubling and twisting processes and drifting into adjacent spindles, or due to the mistaken insertion of double yarn on the winding. A yarn is caused by the yarn clearer; long thick knots and long details are mainly caused by the single merging of the front spinning, the obvious unevenness of the roving, or a small amount of misalignment in the winding process that has not been found and has not been effectively treated.

solution

1) The merging and two-for-one twisting process should reasonably arrange the patrol line to deal with the broken ends in time to reduce the chance of fluttering, and the full bobbins that have fallen should be collected in time;

2) For the phenomenon of double bobbins on the winding, it is necessary to start with the operation training and inspection of the stopper;

3) The frequency of occurrence of abnormal defects is very low. They are generally caused by operating errors and failure to deal with them in time. Once they are formed on the cloth surface, the damage is relatively large, so the operation and inspection of the process after yarn formation must be strengthened, and mild ones may be considered. The measures after the award and before the penalty are found and handled in the workshop of the spinning mill to avoid serious losses caused by the final weaving on the cloth surface;

4) Long thick sections and long details need to be prevented by strengthening the quality control of the front spinning, and reasonably set the clearing parameters and use the clearer to remove;

5) Improve the skills of yarn inspectors so that they can find abnormal defects during finished product inspection.