| 摘要 |
PROBLEM TO BE SOLVED: To provide a molding material manufacturing method capable of highly accurately maintaining inner diameter circularity of a cylindrical barrel part, and capable of preventing generation of dregs of a plating coating film, even if a plate thickness of a raw material metallic plate is varied, in the present invention.SOLUTION: A molding material 1 having a cylindrical barrel part 10 and a flange part 11 formed in an end part of the barrel part, is manufactured by executing multistage restriction to a raw material metallic plate. The multistage restriction includes preliminary restriction for forming a preliminary body 20 having a barrel part element assembly 20a from the raw material metallic plate 2, at least one-time compression restriction for forming the barrel part 10 by restricting the barrel part element assembly 20a while adding pressure adjustable compressive force to the barrel part element assembly 20a by executing after the preliminary restriction and at least one-time finishing squeeze for securing dimensional accuracy in succession to it.SELECTED DRAWING: Figure 5 |
