Discussion on the application effect of carbon fib

Talking about the use effect of carbon fiber top pin on v-pull table

preface

before the objectives meet the experimental methods and standards, the competition in the textile market is becoming increasingly fierce, and the competitiveness depends on product innovation and product quality; Therefore, how to stabilize product quality and improve product quality by using new technologies and processes is the key for enterprises to win in the market. In recent years, our group has widely promoted and applied advanced cots and aprons at home and abroad, giving full play to the excellent performance of new spinning equipment, so that the yarn quality has been significantly improved; However, the use and research of the new carbon fiber top pin is still in the exploratory stage. We have done a lot of comparative tests on the FA507, A512 conventional traction machine and the V traction transformation machine. We think that the effect of using it on the V traction machine is the most ideal, and it has been widely used,, This paper briefly introduces the use of dl14270 carbon fiber top pin produced by Xianyang Dingli Machinery Manufacturing Co., Ltd., a Sino foreign joint venture, in v-pull table

1 Analysis on the mechanism of carbon fiber upper pin improving yarn evenness

according to the analysis of drafting theory and practice, the evenness of output yarn evenness is closely related to the separation of fiber speed change points in the drafting area. The porous media materials available include expanded graphite cloth. The upper and lower apron working surfaces of double apron drafting are in direct contact with the yarn, producing a certain friction boundary to prevent the fiber from changing speed early; The upper and lower pins and the upper and lower rubber rings form a soft and pressure control jaw, which can not only control the movement of short fibers, make the distribution of fiber speed change points close to the front jaw, but also make the fibers held by the front roller jaw be smoothly pulled out, and the requirements for time fluctuation are small

whether the friction field of double apron drafting can be reasonably arranged depends on the distance between the apron jaw and the front roller jaw, as well as the pressure and stability of the apron jaw. There should be both appropriate control force and stable grip force to ensure the uniform and stable speed change of fiber and the improvement of evenness of yarn

during the operation of the upper and lower rubber rings, due to the friction resistance of the rubber ring pin, or the fatigue deformation of the metal upper pin, the working surface of the rubber ring is easy to be loose or concave, resulting in the weakening and instability of the middle friction boundary. The new dl14270 carbon fiber upper pin, the fixed curved surface lower pin and the upper and lower rubber rings form a pair of elastic jaws, which solves the concave phenomenon of the rubber ring, strengthens the control of the middle friction boundary, stabilizes the jaw pressure, improves the stability and elasticity of the rubber ring operation, better holds the fibers, controls the floating fibers, and ensures that the speed change points are distributed close to the front jaw, so as to reduce the evenness CV value and reduce the thickness, detail and neps, The purpose of improving evenness of yarn sliver is achieved

as for the metal upper pin, especially the sx2-6833 upper pin, because of its one-time forming, it cannot self wither the rubber ring tension, and it is easy to cause fatigue deformation and wear during operation, resulting in the distance between the working face and the center of the small iron roller and other process performance parameters not in line with the standard, so that there are friction and slippage in different states between the upper and lower pins and the rubber ring, resulting in uneven and fluctuating fiber movement, and some fibers are out of control, Affect the drafting effect and reduce the stability rate of the CV value of the sliver

2 use effect of dll4270 carbon fiber top pin

we have done a lot of trial spinning on FA507, A512 spinning frame spring cradle pressure machine and v-pull pneumatic pressure machine respectively. The basic situation is as follows

2.1 observation on boarding operation

a) dl14270 carbon fiber upper pin eliminates fatigue deformation and wear of the original metal upper pin after running for a period of time. The rubber ring has no relaxation and concave phenomenon, and the drafting effect is good

b) the influence of the difference in the inner circumference of the apron on the yarn quality is reduced, and the deficiency of the apron is made up

c) since a spring top sheet is installed on the front and middle pressure bar (integrated) of the v-pull pneumatic pressure cradle, the use of carbon fiber upper pin will not cause the adverse phenomena of large jaw pressure fluctuation, insufficient pressure and affecting the evenness due to the poor upper pin spring

2.2 yarn quality comparison

a) variety: C 14.5 tex

b) model: a512v drafting machine and A512, FA507 conventional drafting machine

c) under the spinning conditions of the same spindle, the same roving, the same top roller and apron, the dl14270 carbon fiber top pin and the metal top pin are compared in the spinning test. See Table 1 and table 2 for the comparison

according to the spinning results, the new dl14270 carbon fiber top pin is conducive to the stable operation of the apron, and the yarn quality is significantly better than the metal top pin. The yarn quality of the V drafting machine is also better than that of the conventional drafting machine

3 technical characteristics of dll4270 carbon fiber top pin

3.1 good stiffness and strong deformation resistance

dll4270 carbon fiber top pin takes carbon fiber reinforced polyamide as the main material. This material itself has excellent wear resistance, fatigue resistance, non embrittlement, overall not easy to deform, no regular maintenance and finishing, simple maintenance, long service life and stable quality. The metal upper pin, such as sx2-6833, cannot self adjust the rubber ring tension due to one-time forming, and is under a certain pressure for a long time, resulting in fatigue deformation and working face wear. If it exceeds the limit, the rubber ring will deviate and the working face will be loosened, the control of the fiber is unstable, the thickness and detail will increase, and the evenness CV value will deteriorate seriously

3.2 excellent anti-static ability

due to its excellent anti-static ability, it reduces the adsorption of flying flowers, overcomes the problem that nylon upper pins and metal upper pins are easy to inlay in the past, and the upper pins are easy to clean up, improving work efficiency

3.3 stable and reasonable working angle

in the spinning process, the adjusting plate of the carbon fiber upper pin can adjust the fluctuation of the jaw pressure, and the working angle of the upper pin jaw plate is related to the size and stability of the pressure in the middle of the apron, too large or too small can not control the fiber normally. The working included angle of the dll4270 upper pin adjusting plate is stable at 45 degrees. It can pay attention to turning off the main motor source, automatically tension the upper apron, stabilize the middle pressure, reduce the concave of the upper apron, automatically compensate the influence of the difference in the inner circumference of the apron on the yarn quality, reduce the slippage of the upper apron, and enhance the stability of the apron operation

3.4 the surface is free of burrs and does not damage the rubber ring

the rigid support of the metal upper pin, and its surface burrs and deposited cotton wax will usually damage the inner surface of the rubber ring; The carbon fiber upper pin belongs to elastic support, and the surface is free of burrs, which can prolong the service life of the apron, stabilize the CV value of evenness, and reduce yarn defects

conclusion

through experimental analysis, dl14270 carbon fiber upper pin has the remarkable characteristics of automatic tension of aprons, stable operation, good stiffness, no deformation, good anti-static performance, simple maintenance, long service life and so on. Compared with the traditional metal upper pin, it can effectively reduce the evenness CV value, reduce the coarse details and neps. The promotion and application of this upper pin is another important way to improve the yarn quality, reduce labor and reduce costs