★ What is yarn? Yarn: a generic term for yarn and thread, it is a…
Table of Contents
In the textile industry, the “yarn” means the general term “yarn” and “thread”. Arrange many short fibers or filaments in an approximate parallel state and twisted along the axis to form a slender object with a certain strength and linear density, which is the “yarn”; the “thread” is strands of two or more single yarns.
The Influence of Spinning on Yarn Quality
The yarn has a stable quality only when it formed by the fiber of close length and relatively uniform. In order to get such fibers, the fibers from different production areas and batches must be mixed together. Use cotton opener, cotton mixer and cotton cleaning machine to open, remove and mix all kinds of fibers. In this process, most dust and impurities are removed by gravity and centrifugal force.
Compared with the yarn produced by the intermittent system, the yarn produced on the automatic unit is more uniform and stronger. In addition, the continuous production speed of the automatic unit is higher, the manpower is saved, and the factory is cleaner. No matter what processing system is used, the final quality of yarn mainly depends on the selection of raw materials and the thoroughness of cotton opening, removing impurity removal and cotton blending.
Why We Need Analysis the Yarn Quality?
Textile has two processes, mainly divided into spinning and weaving. The yarn is the secondary raw material of organic fabric and knitted fabric, and suede thread, sewing thread, and embroidered thread are finished yarn. Compared with the fiber, the yarn structure has a more direct influence on the textile internal quality and appearance quality. Therefore, when analyzing the quality of textiles, it is necessary to make a comprehensive and systematic analysis of the structural factors on the yarns used in the textiles such as the type, the shrinkage rate, fineness, twist direction and so on.
The Index for Judging Yarn Quality
Yarn Fineness, Yarn Count, Yarn Density
Fineness refers to the thickness degree of the yarn. Because it is difficult to measure the diameter and size of the cut surface of the yarn in practice, we use the yarn count, that is, the yarn density, to express the yarn thickness. Yarn density refers to the mass or weight of the raw material per unit length.
Yarn density has a great influence on the appearance, handle, weight and mechanical properties of the fabric, so it is necessary to select a reasonable yarn density according to different uses. For example, outerwear fabrics in winter should be heavy, wear-resistant, insulated, and made of medium-Tex or high-Tex yarns. Clothes in summer require lightweight, breathable moisture, made by low-Tex yarn.
Twist, the direction of twist
Yarn twisting means that in order to make the yarn has some physical and mechanical properties, such as strength, elasticity, elongation, luster, handle and so on, it changes the structure of the yarn through produces a relative displacement of the yarn cross-section so that the original parallel fibers are tilted to the central axis of the yarn.
Twisting is a necessary condition for short fibers to form yarns. In addition, twisting will change the yarn density, the yarn strength, and the yarn gloss, thus affecting the fabric structure and properties.
If you want to learn more about yarn twist testing, click Twist Tester.
Single Yarn Strength
Yarn strength, also known as yarn fastness, is a reflection of yarn quality, the yarn must have a certain strength to ensure the normal operation of the knitting process. The yarn strength can be measured by single yarn strength tester, and the index of yarn strength can be divided into two categories: absolute strength and relative strength. Absolute strength refers to the strength the yarn needs that when it is stretched directly to break by an external force, also known as breaking strength, expressed in CN/tex.
If you want to know more about the yarn strength testing, please click Single Yarn Strength Tester.
Appearance Quality of the Yarn
Determination of appearance quality of yarns made of cotton or man-made fibers, or their blends by winding on the blackboard: Observe the yarn samples wound on the blackboard according to the prescribed requirements by a visual method, which to obtain visual effects. Mainly used to observe the slub, thin place, defects, systematic unevenness and NEP of the yarn.
If you want to know more about the appearance quality testing of the yarn, please click Yarn Board.
The Significance of Yarn Quality Testing
Yarns are used as raw materials for weaving, fabrics with different weaving tightness, different fabric surface representation, and different printing and dyeing requirements have different demands on yarn structure. Generally speaking, there is no absolute good or bad yarn, suitable yarn woven suitable cloth, so as to achieve the best use, neither to create a surplus of quality, but also to meet the basic needs of the customer for the goods.
As a professional supplier of textile instruments, we are committed to continuous user experience, TESTEX Textile Testing Equipment is a reliable choice for testing textile quality.