US Patent 7547164 Face milling insert

A face-milling insert, including a chip-removing main cutting edge adjacent to a first clearance surface, and a surface-wiping secondary edge adjacent to a second clearance surface, the main cutting edge forming an angle of 45° with an imaginary straight line in the extension of the secondary edge. Adjacent to a third clearance surface, an intermediate cutting edge is formed between the main cutting edge and the secondary edge, the intermediate cutting edge being shorter than the main cutting edge and forming an angle within a range of 20-40° with the extension line. The intermediate cutting edge transforms into the adjacent edges via arched part edges adjacent to convex clearance surfaces.