MULTI-STAGE PRESS-FORMING METHOD, AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a multi-stage press-forming apparatus capable of press- fitting a ball valve to a caulking hole in a valve body base material and caulking the valve thereto. SOLUTION: This apparatus is provided with first and second caulking hole press-forming mechanisms 17D and 17E for forming the caulking hole 92f in a drawing shaft 92d of the valve body base material 92 on a die block 2 and a ram 6, a ball valve press-fitting mechanism 17G for feeding and press-fitting one ball valve 93 in the caulking hole 92f, and a ball valve caulking mechanism 17H for press-forming the outer circumferential edge of the caulking hole 92f in the valve body base material 92 in a contracting direction and caulking it to the ball valve 93 on the side of the ball valve press-fitting mechanism 17G.