Oval cylinder molding method and elliptic cylinder molding apparatus

摘要

PROBLEM TO BE SOLVED: To shorten a time required for molding furthermore than hitherto, in a molding method of an elliptic cylindrical body for molding a part of the elliptic cylindrical body into a cylindrical shape by spinning.SOLUTION: A molding method of an elliptic cylindrical body for molding a part of the elliptic cylindrical body 9 into a cylindrical shape by spinning has a first molding step for molding the part of the elliptic cylindrical body 9 into the cylindrical shape by using an inside roller 11, and a second molding step for molding a portion molded into the cylindrical shape in the first molding step, further into a cylindrical shape having a reduced diameter by using an outside roller 17.