Patent ID: 7117594

Claim:
A method for producing a piston oil control ring having at least two running rails coated with a wear-resistant coating, said method comprising: before the wear-resistant coating is deposited, forming in at least a part of an outer circumferential surface of a piston oil control ring, two running rail profiles, each provided with a tapered surface region which forms an outer circumferential surface of the running rail profile and simultaneously a running surface of the running rail profile, the running surface having an elevation that projects in a radial direction from a plane of the tapered surface region such that a step is formed between the running surface and the tapered surface region; providing at least each of the running rail profiles with the wear-resistant coating; removing a predetermined amount of the coating in at least the region of the elevations by round lapping to create essentially uniform running surface profiles across the circumference of the ring; and profile grinding the coated running rail profiles to form running rail flanks of the running rails; wherein the running rail flanks are substantially free of the wear-resistant coating.