Two step extrusion method can be proposed to shape the inner helical spline. This method utilizes a stepwise expansion of the inner diameter of the cylindrical workpieces. That is, the diameter of the mandrel having an involute helical spline is increased in two steps. The material used is a 0.15% carbon steel. It should be stressed that the continuous shaping by this method can produce excellent toothed splines without defective part on the tooth. Also noted is the quite low pressure needed for this shaping, comparing to the strength of the dies' material.
展开▼
