Patent ID: 7976251

Claim:
A polygonal indexable insert used for turning, equipped with a nose cutting-edge ( 5 ) and a linear cutting edge ( 6 ) extending continuously therefrom, the indexable insert comprising: a rake face; a first ridge ( 2 ) formed on the rake face; and a second ridge ( 3 ) formed on the rake face, wherein the first ridge ( 2 ) protrudes from a boss surface ( 1 ) towards a nose, and wherein the second ridge ( 3 ) extends continuously from the first ridge ( 2 ) to a slope ( 8 ) connected to a cutting-edge land ( 7 ) of the linear cutting edge ( 6 ), the second ridge ( 3 ) having a height lower than that of the first ridge ( 2 ) and being convex-curved towards a bisecting line (CL) of an apex angle of the nose in plan view, and wherein said first ridge has a rising surface defined by a concave-curved slope.