Look: Whether it is polluted: According to human eyes, whether the ear loop of the mask is stained, colored, or oily.
Color inspection: This can be observed with the human eye. Look at its hue, pattern and stitching. It should not be messy, it should be a very pure hue.
Burr: Generally, it is the burr of some pure cotton yarn. This can also be observed by human eyes. The two sides of the webbing and the overlock should not have serious wool balls and wool.
Needle removal: This can also be observed by human eyes. The ear loop of the mask must not be needle removed;
Take a test: The quality of the webbing is undoubtedly related to the model and specifications of the webbing. Only the standard model and specification can be regarded as the best embodiment of the quality of the webbing.
Thickness detection: accurate measurement with vernier calipers accurate to 0.001, the standard tolerance can not exceed plus or minus 0.001mm.
Total width detection: Use a micrometer to accurately measure jacquard belts with a total width of 1 inch and above. The standard tolerance cannot exceed plus or minus 0.25; the total width of the webbing below 1 inch and 1 inch, the accuracy level cannot exceed plus or minus 0.25 mm. Note: Plain weave and herringbone belts should have as many specifications and models as possible, and the points should not exceed 0.25 points.