摘要 |
A piston ring is formed from a ring blank, e.g., a wire, that has a cross sectional profile including upper and lower surfaces that are generally parallel and disposed between inner and outer peripheral faces. The cross sectional profile also includes a hook area at the outer portion of the lower surface that includes a nose area. The nose area is provided with a radius that is as sharp as possible, and is disposed such that a grinding operation performed on the lower surface, e.g., with a single generally planar grinding surface, will also grind the nose area, thereby truncating the nose area and increasing sharpness of the nose area without having to perform additional machining operations. |