Application of abrasive flow machining technology in microhole machining of spinneret

 In the production of chemical fiber, spinneret is an indispensable precision part of spinning machine. Its function is to extrude fiber bundles with certain thickness and fine texture by spraying the accurately measured spinning melt through the micropores on the spinneret. As the parent body of the new synthetic fiber, the processing quality of the micro-pores on the spinneret is an important condition for ensuring the quality of the finished fiber and good spinning process. 

Therefore, the precision of the spinneret processing on the spinneret is extremely high, and it is also crucial. With the rapid development of chemical fibers, it has also led to the rapid development of spinneret. In order to make the fabric more soft and have good moisture conductivity and comfort, the diameter of the fiber is required to be smaller and smaller, so that the diameter of the spinneret hole is also smaller and smaller. 

 At the same time, in order to meet the needs of the market and improve the production efficiency and processing quality of chemical fibers, the number of veneer holes of the spinneret is also required to increase, and the processing accuracy of the spinneret holes has a very great impact on the quality of chemical fiber products, which puts forward higher requirements for the processing technology and processing technology of the spinneret holes. During microhole drilling of spinneret. The inner surface of the spinneret micropores will leave burrs, which will affect the quality and normal production of the strips. 

 The traditional treatment method is only to remove burring and surface polishing of spinneret micropores under the natural action of spinning melt extrusion through spinneret micropores. This method will cause instability in the early spinning process, fiber breakage and poor spinning quality. In order to improve the process, foreign abrasive flow processing technology is introduced. Because the abrasive flow machining technology has the function of grinding and polishing the hole and cavity of the hidden part, it can play a good machining effect in the machining of spinneret microholes, especially for the microholes with large length-diameter ratio, and has the advantages that other machining methods can not match.

 Compared with the general traditional polishing process, abrasive flow machining technology has the following two advantages in the processing of spinneret microholes: The processing of spinneret microholes, especially for deep holes with relatively large diameter, is difficult to carry out in the hole processing, due to the limitation of size, traditional processing means are more difficult to meet the requirements. 

The tool ------ in abrasive flow machining has random flow and can be adjusted by adding softener. The access area can be unrestricted; Therefore, the abrasive flow technology can be used to process micropores with great advantages. In addition, the abrasive used in the processing of the general polishing process, such as emery, will produce a large normal pressure on the orifice of the small hole when polishing the workpiece cavity, so it will produce a processing error of the horn shape at the orifice. 

The viscoelastic abrasive used in abrasive flow machining technology has population convergence effect, that is, when the viscoelastic abrasive fluid enters the artificial part from the large cross section of the flow path, it will be affected by the viscoelastic characteristics of the fluid, the sudden contraction of the cross section of the flow path, and its own viscoelastic characteristics.

 The corresponding elastic strain energy is stored and its viscosity dissipates in the flow of the workpiece, and there is an obvious drop in the inlet pressure, which can better solve the processing technology problem that is prone to flaking in micro-hole polishing.