METHOD FOR MANUFACTURING OUTER JOINT MEMBER FOR CONSTANT-VELOCITY UNIVERSAL JOINT AND OUTER JOINT MEMBER

摘要

Provided is a method for manufacturing an outer joint member for a constant-velocity universal joint, formed by welding a cup member with which a torque transmission element is engaged and a shaft member, wherein: the cup member and the shaft member are formed from medium-carbon steel; the cup member is prepared by forming a cylindrical section and a base section as a single unit by forge processing and forming a joining end surface on the outer surface of the base section in a mechanical processing step; the shaft member is prepared by forming a joining end surface that is joined to the base section of the cup member in the mechanical processing step; and the joining end surface of the cup member and the joining end surface of the shaft member are abutted and welded by irradiating the abutted sections with a beam from outside the cup member in the radial direction. In the method, the external diameter of the joining end surface of the cup member is set to the same dimension for each joint size; on the internal diameter side of the joining end surface of either the cup member or the shaft member, a projecting surface that projects further radially inward than the internal diameter of the other joining end surface is provided; and an ultrasonic flaw-detecting examination step is provided in which, after welding is performed in the foregoing state, a flaw detection is performed from the surface side of the member with the other joining end surface.