Spin forming a tubular workpiece to form a radial flange on a tubular flange and a bead or thick rim on the radial flange

摘要

A cylindrical workpiece (20) is mounted onto and connected to a mandrel (14) that is itself mounted for rotation about a vertical axis (12). A first end portion of the workpiece (20) is housed within the mandrel (14). A second end portion projects axially outwardly beyond a radial forming surface (60) on the mandrel (14). A first forming roller (30) is mounted on a swing post (52) that is positioned by an adjustable length strut (56). The strut (56) is elongated to swing the post (52) downwardly and place the roller (30) inside the second end portion of the workpiece (20). Then, a lead screw (28) is used for pulling on a base (50) that supports the post (52). This pulls a convex face portion (32) of the roller (30) against the inside of the second end portion of the workpiece (20). Lead screw operation moves the roller (30), causing it to stretch the second end portion of the workpiece (20) and move it up onto and then move it radially outwardly along the forming surface (60). The movement of the roller (30) can be stopped before the roller (30) passes the outer diameter of the forming surface (60). Then, a second forming roller end cam can be used to bend the outer end part of the workpiece radially inwardly and then flat against an adjoining portion of the workpiece (20) that is in contact with the forming surface (60). Or, the roller (30) can be moved radially outwardly until it moves past the outer diameter of the forming surface (60).