The topic of developing new products using the basic principles of embedded spinning was discussed, the design principles of some of the new products developed were introduced, and several key points of twisting in the spinning process were analyzed to lay the foundation for correct application. Embedded spinning technology and the development of new products provide a theoretical basis.
Embedded composite spinning technology (hereinafter referred to as embedded spinning), as a new ring spinning technology, can not only use lower-grade raw materials to spin fine yarns, but also use The principles are adapted appropriately to develop new yarns.
01 Mechanism of insert spinning
The principle of insert spinning is shown in Figure 1 .
Each spindle is fed by double roving and double filament, and the roving sliver reaches the front clamp of the spinning frame after drafting mouth, the filament is directly fed into the front jaw. After the short fiber slivers BE and CF come out of the spinning frame, they intersect with the filaments AE and DF at points E and F. The two two-component spinning EG and FG are then combined together to form embedded spinning.
02 Cross-twisting method
According to the mechanism of insert spinning, The main function of this technology is cross-twisting. Without cross-twisting, there would be no embedded composite. As far as twisting is concerned, there are generally two forms: one is symmetrical twisting, and the other is asymmetrical twisting. The form is shown in Figure 2. The so-called symmetrical twisting is to use a single yarn twisted from two components, filament and short fiber sliver, as the axis. The filament and short fiber sliver are symmetrically twisted around the axis. From a mechanical point of view, the filament and the short fiber sliver are twisted together. The angle between the short fiber whiskers and the twisted single yarn is equal, α=β, see Figure 2(a). The so-called asymmetric twisting means that the angle between the filament and staple fiber sliver and the twisted single yarn is not equal, α≠β. In addition, there are some special twisting forms, namely α=0, or β=0 , see Figure 2(b).
Obviously, its yarn twisting method and yarn structure are better than traditional siro spinning and Two-component spinning is much more complicated. Different twisting methods determine the different structures of yarns, and different structures give yarns different styles and properties. That is, changing the form of twisting can be used to achieve changes in product style.
03 Variety Development
3.1 Low-grade raw materials for spinning fine yarn
Properly configure the distance between the filament and short fiber whiskers, adjust the pre-tension of the filament, so that the short fiber whiskers are output vertically, and the filament and short fiber whiskers are It is the same as the angle between the single yarns after twisting, that is, when α=β, the distance between BE in Figure 1 is stabilized in a certain range. At this time, the distance between BE is the extreme length of the fiber. Short The short fibers in the fiber strands with a length above the EB range will be effectively twisted with the filaments to form yarn. This means that embedded spinning has lower requirements for short hair content in the fiber, providing technical support for spinning fine yarns from low-grade raw materials.
3.2 Spinning ultra-fine special yarn
Using soluble filament and After the short fiber slivers are twisted, the filaments are dissolved during finishing, and ultra-fine special yarns can be spun.
3.3 Multi-component spinning
The filament can be made of silk Silk, cotton thread, hemp thread, gold and silver thread, anti-static thread, etc. For example, one group is composed of wool short fiber strips and polyester filament, and the other group is composed of hemp noil and soluble vinylon filament. After the two groups of four raw materials are compounded, they are symmetrically compounded. The finished yarn becomes wool after dimension reduction. Hemp and polyester 3-component yarn, this 3-component product is significantly different in appearance, feel and wearing performance compared with the traditional three-in-one blended wool, linen and polyester products.
3.4 Color yarn effect
The effect of two component raw materials Different fineness will also cause color effects after compounding, as shown in Figure 3.
3.5 Wrapped yarn
When the angle between the filament and short fiber strands and the twisted single yarn is α=β, the filament and short fiber strands are twisted and wrapped with each other. Angles are equal. When α=0 or β=0, one fiber will be wrapped on another fiber; and when α≠0 or β≠0, the wrapping situation is between the above two. If spun silk and wool are combined, when α=β, the product will have the smoothness and luster of silk and the softness and elasticity of wool. If polyester filament and wool are combined, and α=0 (see Figure 2), the polyester filament is wrapped in wool fibers, and the appearance of the yarn is similar to wool yarn, see Figure 4.
3.6 Core Spun Yarn
Adjust the filament input position, place the filament AG as the core wire in the middle, and give a certain pretension, and place the two short fiber strips BG and CG on both sides. As the twisting proceeds, The left and right strands of whiskers take turns to cover the core wire. The core-spun yarn produced in this way has almost no defects of core wire exposure. The schematic diagram is shown in Figure 5.
04 Notes
4.1 Tension
In embedded spinning, the tension on the short fiber sliver is an important parameter. If the tension on the sliver is too high, the fiber will slip. , causing the evenness of the yarn to deteriorate. Under the conditions that the positions of the filament and short fiber whiskers are fixed and the tension on the single yarn is certain, the tension on the short fiber whiskers depends on the tension of the filament. Obviously, embedded There must be a certain pre-tension on the spun filament, so that the tension on the short fiber sliver will not damage the sliver. However, it must be noted that when the tension on the filament reaches a certain level, the filament and the twisted yarn They are on a straight line, that is, the intersection angle between them is zero. At this time, the tension on the short fiber whiskers is zero, and the original symmetrical twist will become wrapping, that is, the short fiber whiskers are wrapped around the filament. .
4.2 Twisting
Insert spinning two-component twisting When the tension on the short fiber slivers is used to twist the torque of the component, if the tension on the component is zero, it means that the fibers on the component cannot be twisted. Although this situation can It avoids the transfer of the inner and outer layers of fibers during twisting and reduces the generation of hairiness, but it also makes the radial pressure between the fibers very small, the cohesion between the fibers is not tight, and the fiber strips are easy to break. Obviously, a certain tension is required Twist the fiber strips to increase the cohesion between fibers.
4.3 Angle
Spinning tension fluctuates, and the size and angle of the two triangles are constantly changing. Spin breakages are mostly caused by excessive tension on the short fiber strands, and the tension between the fibers. The cohesion force is insufficient to resist the tension. The tension on the short fiber sliver decreases as the angle between the filament and the single yarn decreases, and increases as the angle between the sliver and the single yarn increases. . In other words, in order to avoid breakage of short fiber strands, the angle between the filament and the single yarn should be small.
05 Conclusion
The biggest feature of embedded spinning is that the restrictions on the short fiber content and the shortest fiber length in the fiber sliver are relatively loose, which provides good conditions for the use of short fiber raw materials. It provides a new way. In addition, the yarn produced by insert spinning has less hairiness and even evenness. The use of insert spinning provides the possibility of rationally using low-grade raw materials to spin high-end products.</p
