FYI Tester Instrument

  Fiber fineness refers to the thickness of the fiber. Fineness is one of the important morphological dimensions and quality indicators of fibers. Fiber fineness is closely related to spinning process and yarn quality, and directly affects fabric style. Fiber fineness index and its conversion Direct indicator It is expressed directly by the geometry index of the fiber. Such as diameter (d), projected width, cross-sectional area, cross-sectional perimeter, specific surface area, etc. Fiber diameter was observed by optical microscope or electron microscope. It can be used to characterize the fineness of wool and its animal hair, and round chemical fibers. Indirect indicators Expressed indirectly by the relationship between fiber length and mass Gk–the weight of the fiber at the specified moisture regain (g) L–fiber length (m). 1. Linear density : Tex (Nt), decitex (Ndt) Tex: The mass in grams of a 1000-meter-long fiber at a given moisture regain. dtex: The mass in grams of a 10,000-meter

  Introduction Ring spinning is currently the most widely used spinning method in the market. The drafted slivers or roving are drawn in through the ring traveler, the bobbin is wound faster than the traveler, and the cotton yarn is twisted into a spun yarn. Widely used in the spinning of various short fibers. Such as carding, combing and blending, the traveler is driven by the bobbin through the yarn sliver to rotate around the steel ring. Twisting, at the same time, the friction of the steel ring makes the rotation speed slightly smaller than the bobbin to be wound. The spinning speed is high, and the shape of the ring-spun yarn is a conical helix with fibers mostly transferred from inside to outside, so that the fibers are wound and connected inside and outside the yarn. The yarn has a compact structure and high strength. Ring spinning process Combed Blowing room—carding——pre-drawing——strips and coiling——combing——first drawing——secondary drawing——roving——spun yarn——winding Carding

The  roving frame  is the main equipment of cotton spinning, and it is also one of the most complex equipment. The quality of the roving frame directly affects the physical performance of the yarn, such as evenness, weight unevenness, strength, and yarn defects. It also plays a decisive role in spinning output, energy consumption, labor, materials, labor productivity, cost, benefit, and floor area. Roving, sliver and yarn A roving frame, also known as a roving machine or fly frame, produces roving from a sliver. The sliver is created in a draw frame, which is located upstream of the yarn manufacturing process. The roving is the raw material used to make yarn, such as in a ring spinning machine. As a result, the roving is much thicker than yarn yet much thinner than a sliver. Tasks for roving frame There are three tasks on the roving frame, namely drafting, twisting and winding. Drafting: lengthen and thin the cooked sliver, improve the parallelism and separation of fiber straightening;

  Draw frame is applicable for drafting fibers of bending cotton sliver to be straight and improve the degree of uniformity of cotton sliver through combining. The importance of  draw frame After the cotton has been opened and carded, if the raw sliver is spun directly without passing through the draw frame, there will be problems. 1. Poor straightening and parallelism of fibers in raw sliver may lead to uneven yarn evenness and poor strength. 2. A small amount of tufts in the card sliver can result in a lot of thick places and fine details. Tasks for the draw frame 1. Merging: Improves evenness of medium and long segments of sliver. 2. Drafting: Improve the straightening and separation of fibers. 3. Mixing: Thoroughly mix the fibers 4. Quantitative control: Control the fineness of the sliver according to the fineness of the spun yarn. 5. Sliver: Winding into appropriate rolls for use in subsequent processes. The basic principles of drawing and drafting are introduced  here.