Cotton knitting yarn strength quality standard

Cotton yarn quality standard

As the semi-products imported into the next process of yarn sales and the enterprise, the inspection and grading of this white cotton yarn is generally implemented in accordance with GB/T398-93 issued by the State Bureau of Technical Supervision. Since no new standards have been established, most domestic manufacturers only use this standard to assess yarn grades, and more use the Uster Bulletin to measure yarn quality.

Wool yarn quality standards

Generally, wool yarns are evaluated as semi-products within the enterprise. There are no national standards, only industry standards or local enterprise standards.

Generally, it is graded by physical indexes, and appearance defects are graded. The grading indexes are:

① Special number deviation; 

② Uneven weight; 

③ Uneven twist;

④ The average strength is not less than CN (breaking length); 

⑤ Low-grade fiber content;

⑥ Oil content; 

⑦ Dyeing fastness.

Among them, the three indicators of ⑤⑥⑦ are considered when selling yarn

The grading indicators are: ① yarn defect ② big belly yarn

Use blackboard sticks or uster sticks

Woollen and worsted spinning

Ramie yarn quality standards

Ministerial standard FZ/T32002-92

The inherent quality of yarn: strength and unevenness, uneven weight, weight deviation, etc.

Based on the appearance quality of the yarn: evenness of the yarn, coarse details, and hemp grains.

Strand: Determined by single yarn strength, unevenness, weight deviation, etc., rated by thick knots.

Spun silk

The quality standard issued by the Ministry of Quality Standard FZ/T42002-97 mulberry silk silk index: ① breaking length; ② uneven count; ③ uneven dryness; ④ cleanliness; ⑤ flaws in kilometers; ⑥ count deviation; ⑦ lack of strength Uniformity; ⑧ Elongation at break; ⑨ Twist deviation rate; ⑩ Twist unevenness. Among them: ②③⑤ has an effect on the appearance of the fabric ③④⑤ Observe with a blackboard.

It is a reference index for the quality classification of fibers, slivers, rovings and yarns in the textile industry around the world. The last statistical bulletin was published in 2007, and a new statistical bulletin will be published in 2012. When the Uster Statistical Bulletin is used as a standard for comparison, special flaws and defects in the total quality of the yarn can be clearly manifested, which can be quickly transformed into improvement measures in the production process. USTER conducts tests on fibers, semi-finished products, and spun yarns in users all over the world and factories in Switzerland, and then analyzes the data. The statistical values of the test results are published every 3 to 5 years, which is the USTER statistical value. The statistical value is generally divided into 5%, 25%, 50%, 75%, 95%. It is generally considered that 50% of the statistical value is at a general level; 25% and below are at an advanced level; 75% and above are at a poor level.

Beginning in 1957, USTER company introduced the USTER statistical value, which is the statistical value of the yarn test results sampled from all over the world with the USTER instrument. It is published in the USTER News Bulletin every few years. NEWS BULLETIN) released a total of five levels of yarn products including cotton and wool. They are represented by statistical graphs. The abscissa is the linear density (number) of the yarn, and the ordinate is the value of the quality index. The dual logarithmic coordinates are used.