Abstract: This paper introduced the research results on pressure distribution in rotary forging the cylinder. The differences between rotary forging and other pressure process methods are “mushroom effect” and “centre tense stress”. According to the metal flow rule in rotary forging, the contact zone may be divided into two zones: centre----tangential strain zone, border----diametral strain zone. Using above mentioned viewpoint after made some hypotheses, the pressure distribution had been calculated. This result is conform to actual situation. This conclusion is of great importance for correctly understanding process characteristics of rotary forging, analyzing reasones about damaged dies and improving the quality of the quality of the products.

Key words: 摆动辗压, 变形, 压力, blade pressure angle, cutting principle, helical motion, spiral bevel and hypoid gears, duplex helical method