This is a very practical and good question. If you don't have an instrument, you can try the following 5 steps:
1. First observe the surface to see whether there are impurities, oil stains, rust stains, thick spots, different-colored fibers, neps, etc.;
2. Pull out the yarn for a certain distance to see if the strips (fat), dry (thin) are even;
3. Pull hard to feel whether it is tough;
4. The above 3 points are all ok. You can use the loom to make a sample to see whether it is easy to weave and the overall quality of the cloth;
5. At the same time, cut a section of yarn, stir it with warm water and a little laundry detergent, and briefly test the color fastness. The above simple steps involve five important indicators of yarn quality: yarn defects, evenness, strength, twist, and color fastness. The five points complement each other to determine the quality level of the yarn. The following content is expanded, and I hope it will be useful to you.
(1). Yarn defects Yarn defects refer to defects in the yarn, which will affect the appearance and smoothness, such as thick details, colored yarn, slugs, impurities, oily yarn, rust stains, etc. Yarn defects can be measured with a yarn defect meter.
(2). Sleekness Sleekness refers to the degree to which the thickness of the yarn is uniform. The thickness of yarns with the same count should be uniform in theory. However, during the spinning process, if the operation is improper and the craftsmanship is not meticulous, yarns with uneven thickness will be produced, resulting in the finished product showing clouds of different shades. spot.
(3.) The strength of strong yarn refers to the toughness of a yarn and its fastness. In spinning, the raw materials must withstand certain tension and load, and the spun yarn must have a certain strength to ensure the normal progress of the weaving process. The strength of the yarn can be measured with a single yarn strength machine, and is generally expressed in terms of breaking strength (the force used when the yarn is broken on the strength machine, the unit is CN/tex (gf/tex).
(4). Twist In the spinning machine of woolen spinning, the yarn is stretched and twisted at the same time. The purpose of twisting is to make the yarn have better strength. Twisting is like winding a yarn, whether it is tight or tight. Loose control. If the twist is too high, the yarn will be twisted and braided during weaving, the elasticity of the fabric will be reduced, and small braided yarn knot defects will easily form on the surface of the fabric. In addition, excessive yarn knots will also easily damage the parts of the loom. If the twist is too low, the strength of the yarn will be affected, the breakage rate will increase, and the workers who stop the train will have to keep knotting, the yarn production rate will be low, and the output will decrease; too many knots on the fabric will also affect the appearance quality of knitted products. The twist of yarn can be measured with a twist meter.
(5). Color fastness means dyeing fastness, which means that the dyed yarn is subjected to external washing, ironing, friction, light, saliva immersion, water stains, sweat stains, chemicals, etc. during use or processing. The degree of fading is a routine test item in yarn quality testing. Dark colors, light colors, bright colors, fluorescent colors, interlaced colors and other colors need to maintain a certain degree of fastness in order to meet the needs of wear and durability. The color fastness of the yarn can be sent to the testing department for testing of various color fastness indicators.
