A study of process and die design for ball valve forming from stainless steel tube

In this paper, two process and die design methods for ball valve forming from stainless steel tubes are compared: one is the tube hydroforming method (THFM), and the other is the tube nosing method (TNSM). Simulations on hydraulic expansion, axial feeding, and tube nosing of the ball shell forming with the two methods using the program DEFORM-3D are carried out. The influence of the two methods on workpiece formability and wall thickness distribution of ball valve forming is examined. A tube nosing experiment is carried out with a SUS304 stainless steel tube at room temperature. An accepted product of ball valve satisfying the industrial demand is obtained using TNSM.