Yarn quality evaluation includes internal quality and appearance quality:

        Basically, it is based on physical indicators and appearance defects. However, the physical index items and appearance defect items of different types and different uses of yarn are different.

        Yarn quality standards include national standards (approved and issued by the National Science Committee), ministerial standards (approved and issued by the Ministry of textile industry), and enterprise standards (formulated by provincial and municipal industrial departments).

The basis and grading of common yarn quality evaluation are as follows:

Quality evaluation of cotton yarn

Cotton yarn refers to cotton yarn. Take the production volume of three shifts a day and night as a batch to evaluate.

Items of cotton yarn rating

1. Single yarn breaking coefficient of variation

2. Coefficient of variation of 100 meter weight

3. Evenness of sliver

4. Number of neps per gram

5. Total number of neps and impurities in one gram

Basis for cotton thread rating: 1.2.4.5