1 Overview Yarn line density is one of the commonly used indicators to describe the degree of yarn thickness, the statutory unit is Teksi (Tex), that is, each km (km) yarn (or single wire) with a fixed weight (g). The yarn density determines the variety, use, style and physical mechanical properties of the fabric.
Yarn density test to determine the length of the sample, the quality of which the length of the measurement of the frame-type measuring instrument, the quality of the determination of the equal arm balance or electronic balance.
2 Purposes and requirements
Through the test, grasps the yarn line density The test method, the training proficiency uses the instrument the ability, understands affects the yarn line density test result the factor, and learns each index the calculation method.
3 Adoption of standards
⒊1 Adopt standard: GB/t 4743, ISO 2060.2 "textile rolling yarn yarn density measurement method of twisted yarn" ⒊2 related standards: GB 6529 "textile moisture and Test standard atmosphere", GB/t 9995 "Textile materials moisture content and moisture regain determination oven drying method", GB/t 9994 "textile materials public set moisture regain", GB/t 6503 "synthetic filament moisture regain test method", GB/t
6502 "sampling method of synthetic filament wire", fz/t 10035 "general system of textile material marking line density (Teksi)", fz/t 01015, ISO 6741-1 "determination and calculation of the quality of commercial quality of textile fiber and yarn delivered goods", etc.
4 Instruments and Appliances
⒋1 Yarn Length measuring instrument (Fig 1 is the YG086 type wisp yarn length meter).
⒋2 Ventilation Type Quick oven (Figure 2 is y802k type quick oven), chain balance or electronic balance (sensitivity is 1mg or 10mg).
Wisp yarn length meter is controlled by single chip microcomputer, can be set around the number of laps, each circle (the circumference of the yarn box) a meter, preload tension can be adjusted, the instrument started after the motor-driven yarn frame rotation, according to the provisions around a certain length of wisp yarn (a twisted), the wisp weighing as Sample.
Then the winding yarn is dried through the ventilation type fast oven, the sample is weighed in the box, and the yarn density is calculated according to the measured mass.
6 sampling Under the precondition of preventing the change of the moisture regain of the sample, the samples were sampled by random sampling method ⒍1.
The production enterprise should arrange the sampling according to the requirement of the testing cycle and the number of the same variety equipment, according to the principle of "general monitoring in one cycle". The number of ⒍2 trade samples may be extracted in accordance with the provisions of product standards or related agreements.
In the absence of such standards, according to the requirements of the test results of precision and probability level, the use of mathematical statistical methods to determine the calculation.
7 sample The ⒎1 filament yarn is tested at least 4 rolls, with at least 10 rolls of staple yarn.
At least 1 strands of yarn are shaken per roll.
⒎2 If you want to calculate the linear density coefficient of variation, at least 20 samples should be measured.
8 Environment and correction Standard atmospheres for humidity and testing are set at level two of GB 6529, and non-standard atmospheres are amended in 14 or according to product standards for the determination of moisture in textile materials by the "four oven method". The sample is placed in the standard atmosphere for pre-humidity, not less than 4h, and then exposed to the test in the standard atmosphere of 24h, or exposed to at least 30min, the quality of change is not less than 0.1%.