How to match cotton

How to match cotton (1) Classification Classification is to classify the raw cotton suitable for spinning a certain type of yarn into one category based on the properties of r...

How to match cotton

(1) Classification
Classification is to classify the raw cotton suitable for spinning a certain type of yarn into one category based on the properties of raw cotton and the different requirements of various yarns, and to form the mixed cotton of that type of spinning yarn. When classifying raw cotton, arrange extra-fine and fine special yarns first, then medium and thick special yarns; arrange key products first, and then arrange general or low-end products. At the same time, the following issues should be paid attention to:
1. Raw cotton resources
When classifying, we should consider the cotton season changes and cotton arrival trends, as well as the inventory of various raw cottons. We must look forward and backward and leave room for action.
2. Climatic conditions
In the severe winter and dry season, in order to facilitate the operator’s operation, the yarn strength needs to be appropriately increased. During the rainy season, raw cotton with good maturity and less neps and impurities can be appropriately mixed into the mixed cotton. Proper scheduling can stabilize production.
3. Mechanical properties
When the machine models and performances used are different, raw cotton should be selected reasonably according to the different efficiencies of opening, impurity removal, drafting, etc.
4. Differences in properties of raw cotton
Adopting the cotton blending method of “short, medium and long” and “coarse, medium and fine” will help improve the evenness and strength of the yarn, and the smaller the difference in properties between successive batches of cotton will be. The better.
5. Balance of indicators
Various special yarns have different quality indicators, and sometimes there are conflicts between various indicators, which must be considered when classifying raw cotton. In addition, other technical and economic indicators often produce contradictions. For example, in a certain period, the output and quality cannot meet the indicators, and better quality raw cotton needs to be used. In another period, cost and cotton consumption become problems, and some low-grade cotton needs to be used. Cotton, recycled cotton, reused cotton. When classifying, a comprehensive balance must be implemented to achieve all-round standards to the greatest extent possible. In actual production, due to different equipment, different mechanical conditions, and different process conditions, differences in yarn quality will occur even if the same cotton blend is used.
(2) Queuing
Queuing is to divide the same type of raw cotton into several teams on the basis of classification, and arrange raw cotton with similar regions and properties into one team. When a batch of raw cotton is used up, the same team will be Another batch of raw cotton takes over. When queuing, you should pay attention to the following issues:
1. Main component
When matching cotton, select several teams of raw cotton with similar properties as the main component. Generally, the main component accounts for 70%. The origin can be the main body, or the length and linear density can be the main body.
2. Number of teams and mixing percentage
Generally, 5-8 teams are used. If the number of teams is large, production management will be troublesome. If the number of teams is small, the percentage of mixing will be high and the properties of the mixed cotton will be greatly different. The percentage of raw cotton mixed in each team is controlled within 25%.
3. Cross-compensation
When a certain indicator of a certain mark in a batch of mixed cotton is too poor or too good, another team of corresponding marks with better or worse quality will be selected to receive the batch at the same time to compensate for each other. However, no more than 2 marks should be changed on the same day, and the proportion should not exceed 25%.
4. Frequently adjust and adjust less
That is to say, when receiving a batch, the proportion of each transfer is smaller and the number of transfers is more, so that the quality of the mixed cotton is stable. For example, if a batch of raw cotton is mixed with 25%, before it is almost used up, use about 15% of the next batch of raw cotton. After the first batch of raw cotton is used up, then increase the next batch of raw cotton to 25% to avoid sudden changes in the properties of the mixed cotton.
 (3) Control of differences in properties of raw cotton

 (4) Use of recycled and reused cotton
Spinning production The back flowers, return strips, roving ends, roller flowers, etc. in the process are called back flowers and can be mixed with mixed cotton, but the mixing amount should not exceed 5%. Reused cotton includes waste from the blowroom machine (commonly known as system seed), waste from the carding machine, waste from the chopper and needle, and waste from the combing machine. The noils of the blowroom machine have less spinnable fibers, short fibers, and contain a lot of small impurities. After treatment, they are often mixed with yarns with larger linear density or secondary brand yarns; Zhandaohua is generally downgraded and mixed, and combed noils are 5~20% can be mixed in thick special yarns, and 1~5% can also be mixed in medium special yarns.