The process of cross wedge rolling and final forging for valve blank was studied by the method of numerical simulation combined with practice. According to the requirement of cross wedge rolling process and the final forging process of valve blank, several kinds of preformed blanks with different transition fillet radii were designed, and the final forging process was simulated by the finite element software. Some deforming regulations of metal flow, the maximum forming load of the billet with different transition fillet final and the contact conditions of the blank and the concave die were analyzed. The results show that compared with the transition fillet radius of the forging part, the closer is the fillet radius of the blank and the forging part, the better is the comprehensive effect. When the fillet radius of the blank is too small, the forming load becomes smaller, but the oxide skin of the blank transition fillet radius is difficult to be removed and a shallow extrusion traces occurs. In addition, the larger is the blank fillet radius, the greater is the forming load. The extrusion traces are deeply produced and the mold will be seriously worn, and thereby the die life will be shortened.
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