Friction welding flash trap seal

Abstract

A friction welded part having a sealed flash trap is disclosed, along with a method for producing such parts. The friction welded parts have a hollow cylindrical part and a second part to which the hollow cylindrical part is friction welded. There is an internal flash trap in the region of the weld, and the hollow cylindrical part is pinched inwardly or a conical flange on the flash trap is deformed outwardly so as to seal the flash collecting portions of the flash trap from the hollow portion of the hollow cylindrical part remote from the weld. The method involves the conventional steps of rotating the parts with respect to each other under pressure, stopping the rotation, and exerting high pressure to form the weld. In accordance with the invention, the hollow cylindrical part in the region adjacent the flash trap is then forced inwardly or a flange on the flash trap is forced outwardly so as to effect the seal. Rolling is the preferred method of forcing the hollow cylindrical part inwardly, and is preferably carried out immediately after the welding, so that the remaining weld heat can be used to advantage. A mandrel or punch is used if a flange on the flash trap is forced outwardly.

Dependencies are inferred from the claim text.