Abstract: A three-part oil scraper ring includes an expander spring and two scraper rings, comprising a ring body (4) having an upper flank (6), a lower flank (8), a ring inner surface (10) and a ring outer surface (12) which has a ring outer contour (14) in cross-section in axial direction (A). The ring body (4) has a height H which corresponds to the greatest distance of the upper flank (6) to the lower flank (8). The ring outer contour (14) forms a running surface (16) which has a radius of curvature R which is smaller than the height H of the scraper ring (2) by a factor between 1.5 to 6, preferably between 3 to 5 and further preferably between 3.5 to 4.5.

Abstract: A stepped piston ring (2) includes a ring outer side (5), an upper ring flank (6), and a lower ring flank (8). The ring outer side (5) on the upper edge has a notch (10, so that only a lower portion of the ring outer side (5) forms a contact surface (4).

Abstract: A three-part oil scraper ring includes an expander spring and two scraper rings, comprising a ring body (4) having an upper flank (6), a lower flank (8), a ring inner surface (10) and a ring outer surface (12) which has a ring outer contour (14) in cross-section in axial direction (A). The ring body (4) has a height H which corresponds to the greatest distance of the upper flank (6) to the lower flank (8). The ring outer contour (14) forms a running surface (16) which has a radius of curvature R which is smaller than the height H of the scraper ring (2) by a factor between 1.5 to 6, preferably between 3 to 5 and further preferably between 3.5 to 4.5.

Abstract: A stepped piston ring (2) includes a ring outer side (5), an upper ring flank (6), and a lower ring flank (8). The ring outer side (5) on the upper edge has a notch (10, so that only a lower portion of the ring outer side (5) forms a contact surface (4).

Abstract: The invention relates to a piston ring of a reciprocating piston internal combustion engine, comprising a ring body with an open abutment, a radially outer running surface side, a radially inner circumferential side, two axially opposite flank sides, an at least partial coating (B) on the running surface side, and a circumferential recess (A) in the lower region of the running surface, said recess ending outside of the abutment region (C). The running surface side has a spherical profile with a pivot point which is arranged at a height h2<i/> of 55-80% of the axial height h of the piston ring.

Abstract: The present invention relates to a cylinder liner with a covering layer, and a wear-resistant inner layer, arranged inside of the cylinder liner, wherein a thickness of the wear-resistant inner layer, decreases on at least one axial end of the cylinder liner.

Abstract: The present invention relates to a cylinder liner with a covering layer, and a wear-resistant inner layer, arranged inside of the cylinder liner, wherein a thickness of the wear-resistant inner layer, decreases on at least one axial end of the cylinder liner.