Abstract: A piston ring having a keystone shape and an orientation feature on one of its surfaces for ensuring proper orientation of the ring during installation. The piston ring preferably has an outer peripheral surface that includes a sealing land with a nitride hardened surface to resist wear during the service life of the piston ring. A tapered surface is also provided on the outer peripheral surface adjacent to the sealing land.

Abstract: A base body of a piston ring has an electroplated chrome or gas nitrided sub-layer formed on its outer peripheral face. The sub-layer is face-lapped, roughened through grit blasting, and then oil lapped to remove the asperities. The resulting plateau-reservoir surface has a smooth plateau and a number of reservoirs. A metallic nitride face coating is applied to the sub-layer. The reservoirs provide additional surface area to promote the bonding between the metallic nitride and the sub-layer. The coating does not eliminate the reservoirs, however. Thus, the reservoirs provide the additional function of storing lubricating oil which may be used during piston ring operation to eliminated unwanted wear.

Abstract: An improved method for manufacturing a camshaft. A robot positions a drive gear on a shaft and the gear is laser welded to the shaft. The cam lobes are axially and rotatively positioned on the shaft utilizing a robot and are laser welded to the shaft. Bearing journal sleeves also may be axially positioned on the shaft by a robot and may be laser welded to the shaft. Preferably, the gear, the cam lobes and any bearing journal sleeves are welded utilizing a robot mounted laser welder to achieve fully automated production.