This paper research with cone and cylinder as object,applys the methodes of combining figures and numbers to analyse the opening up of cutting out and intersection, and set up corresponding mathe model.

This article introduces the technology of trimming the aditus department of the thin-wall barrel-type piece based on the principles of transversal truncation about the polyurethane rubber.

Through the second die ,The roughness of shear sectional plane was assured;Through added the cam driver , The discharging was easy in the bend?The structure of die ensureed the technique requirement and the production efficiency was raisen.