A manufacturing method of a rotating element including a cylindrical fitting portion having a pair of circumferential end portions forming an axial slit between the circumferential end portions, the cylindrical fitting portion being serration-fitted to a rotating shaft, includes: clamping the fitting portion by a clamp jig so that the fitting portion is elastically deformed in an elliptical shape; forming a female serration arranged in an elliptical shape by use of a tool having an elliptical section, the female serration being formed on an inner peripheral surface of the fitting portion elastically deformed in the elliptical shape; and releasing the clamping by the clamp jig so that the arrangement of the female serration is changed to a perfect-circle shape from the elliptical shape.

A manufacturing assembly for installing a snap ring into a bore of a multi-axial joint includes a ram tool configured to axially force the snap ring through the bore towards a retention groove with the snap ring in a constricted configuration. An axially distal end of the ram tool includes one or more engagement elements having a tapered engagement surface configured to apply a radially outward force to the snap ring during passage thereof through the bore to urge the snap ring to expand from the constricted configuration back towards an original configuration upon the snap ring reaching the retention groove. A funnel tool configured to constrict and the direct the snap ring into the bore includes an alignment key configured for reception within a keyway of the ram tool during installation of the snap ring to orient the funnel tool and the snap ring relative to the ram tool.

Provided is a method and apparatus for refining a ball joint stud. The method includes receiving and releasably securing the ball joint stud in a holder between a first die and a second die. The method further includes translating one or more of the first die and the second die towards the remaining die to apply a compression pressure to the ball joint stud. The compression pressure causes a plastic radial compression of the ball joint stud to a stroke length. The stroke length may be to induce a residual stress in the ball joint stud or increase a surface hardness of the ball joint stud. The first die and second die each include a contact surface configured to interface with the ball joint stud. The method may further include rotating one or more of the first die and the second die during the application of the compression pressure.