DIE ASSEMBLY AND METHOD FOR INTERIOR ROLL NECKING-IN TUBULAR MEMBER

摘要

A die assembly and method for interior roll-necking-in an end portion of a tubular member. The die assembly comprises an outer reducing die and a rotatable spindle assembly concentrically-mounted therewithin and axially-movable in relation thereto. The spindle assembly includes a plunger having cam surfaces thereon and a pilot in turn including a housing having an axial bore therethrough and a radial slot communicating therewith, and a free-wheeling roller axially-mounted between the legs of a substantially U-shaped bracket radially slideably seated within the slot. The bracket includes bracket cam surfaces cooperative with plunger cam surfaces for moving the roller radially when the plunger is moved axially through the housing. The pilot can include biasing means for biasing the bracket and roller radially inward toward the plunger, and cushioning means loosely pin-mounted within cavities in the bracket legs to allow the shoes to slide radially in the cavities to compensate for variations in wall thickness of the tubular member.