Advanced Design of Hexagonal Cavities for Bolt Heading Tools Using Optimum Analysis Technique

Bolt heading process is one of the popular working process. The punch side die is composed from several steel rings and split segments. The assembly is designed to avoid a stress concentration and to satisfy economic aspect. This paper describes a design methodology using a new design concept, which is aimed at achieving uniform stress distribution in the die system by considering discontinuities of stress transmission on the interfaces can be achieved between each segment and the stress ring. The new system which consists of trapezoidal segments and hexagonal envelope ring, is ensured the high durability by the finite element method. And the segment with a hole and internal pressure is confirmed to increase its durability.