test of evenness of yarn:
In the field of the production of filament yarns, in addition to common tests such as measuring breaking force and elongation at break, one of the most important cases of quality control for this type of yarn is to check their evenness.
test of evenness of yarn
The yarn evenness tester is used to check this quality characteristic of the yarn. It has been designed based on changes in capacitance, which changes in proportion to the change in linear density, and the output of the device provides useful information such as statistical data, diagram, spectrogram, standard deviation vs. length curve, etc.
Video of the steps of performing this test in the laboratory of Sirang Co.
International standards for this test are ASTM D1425 and ISO 16549.
To perform the weight uniformity test of 260 dtex/144f POY yarn, after passing the yarn through the relevant guides and selecting the appropriate slot from the machine software, according to the standard, the length of the sample is 400 meters and the stretching speed is 400 meters per minute. It should be noted that this device is also capable of testing at a speed of 800 meters per minute.
The graph scale is set at 12.5% and the twisting speed and twisting direction are set at 6000 rpm and Z, respectively. The test time is also considered 2.5 minutes according to the standard. It is worth mentioning that the number of times and length of the test can also be adjusted.