球面零件冷挤压脱模机构研究与模芯失效分析

Research on Cold Extrusion Demoulding Mechanism for Spherical Parts and Failure Analysis of the Mold Core

内球面零件精密冷挤成形后,由于球面回弹对模芯产生很大正压力,导致轴向顶出脱模阻力大,顶出时可能会使内球面零件端口发生严重变形,因此考虑采用旋转顶出方式来消除模芯和滑履球面摩擦力进行脱模,文中对旋转顶出的脱模方法原理进行分析,并计算重要参数螺旋升角,设计出合理旋转顶出脱模机构,最后通过工艺实验来证明旋转顶出的脱模方式具有脱模阻力小、成形精度高等优点。

After the precision cold extrusion of inner spherical parts,due to the great positive pressure of spherical rebound on the mold core,the axial ejection demoulding resistance is large,and the port of inner spherical parts is seriously deformed during ejection.Therefore,the rotary ejection method is considered to eliminate the friction between the mold core and the sliding shoe spherical surface for demoulding.This paper analyzes the principle of the demoulding method of rotary ejection.The important parameter spiral rise angle is calculated,and a reasonable rotary ejector demoulding mechanism is designed.Finally,the process experiment shows that the rotary ejector demoulding method has the advantages of low demoulding resistance and high forming precision.