据国外报导,对低炭钢的中空筒件用冷挤压法一次挤出孔深和孔径比为4的深孔筒,既得到较好的同心度,又避免了冲头和制件间的粘着。对于保证得到高同心度的措施是采用带有和冲头固定板同样大小的冲头导向环,靠在园周方向上排列的滚珠和冲头座的内园导向。由于挤深孔时,在挤压开始阶段,冲头 According to foreign reports, the hollow tube of low carbon steel with a cold extrusion method once the hole depth and aperture ratio of 4 deep hole tube, both get better concentricity, but also to avoid the punch and the workpiece adhesion. To ensure high concentricity measures are used with the punch and the fixed plate with the same size punch guide ring, by the circumferential direction of the ball and the punch base aligned with the interior guide. As the hole is squeezed, the punch at the beginning of the squeeze