An oil scraper piston ring and a method for producing it in which a base body is provided with a running surface profile by machining the radially outer circumferential surface thereof, the running surface profile including two running surface lands and an interposed groove, wherein the running surface profile corresponds to that of the finished oil scraper piston ring, and on the groove side, seen in the circumferential direction, drainage holes are introduced into the groove base, at least the running surface lands are provided with a wear-resistant PVD, DLC or TaC layer and, if needed, the wear-resistant layer is subjected to a polishing, honing or lapping operation.

An oil scraper piston ring and a method for producing it in which a base body is provided with a running surface profile by machining the radially outer circumferential surface thereof, the running surface profile including two running surface lands and an interposed groove, wherein the running surface profile corresponds to that of the finished oil scraper piston ring, and on the groove side, seen in the circumferential direction, drainage holes are introduced into the groove base, at least the running surface lands are provided with a wear-resistant PVD, DLC or TaC layer and, if needed, the wear-resistant layer is subjected to a polishing, honing or lapping operation.

A method of forming a piston ring includes providing a base portion formed of a metallic material, the base portion having a first surface, and a second surface that is opposite the first surface, the base portion configured to interface with a piston ring groove. The method includes grinding the first surface to form a reference surface, applying a chromium layer to the second surface, and grinding the chromium layer to reduce a surface roughness of the chromium layer.

A method of forming a piston ring includes providing a base portion formed of a metallic material, the base portion having a first surface, and a second surface that is opposite the first surface, the base portion configured to interface with a piston ring groove. The method includes grinding the first surface to form a reference surface, applying a chromium layer to the second surface, and grinding the chromium layer to reduce a surface roughness of the chromium layer.

An oil scraper piston ring, includes a base body that has a running face region provided with running lands, an inner circumferential surface, upper and lower flanks, and oil drainage boreholes/slots extending between the running lands up to the inner circumferential surface. Manufacturing steps to produce the oil scraper piston rings are performed in a plurality of oil scraper piston ring blanks mounted on the same round mandrel.

An oil scraper piston ring, includes a base body that has a running face region provided with running lands, an inner circumferential surface, upper and lower flanks, and oil drainage boreholes/slots extending between the running lands up to the inner circumferential surface. Manufacturing steps to produce the oil scraper piston rings are performed in a plurality of oil scraper piston ring blanks mounted on the same round mandrel.

An unchamfered piston ring that is pre-treated by grit blasting to a defined roughness, followed by PVD coating with a metal nitride to a thickness of at least 10 m, leaving peaks and valleys in the coated piston ring. The coated piston ring is then lapped to remove the peaks without penetrating the coating, so that valleys and plateaus remain in the coated surface. The resulting piston ring exhibits superior coating retention due to the increased surface area created by the grit blasting, and yet also superior performance, as the cavities remaining increase the porosity of the coating and thus enhance the lubrication of the ring.