Detachable cutting plate for descaling round bars on a centerless machine

A detachable cutting plate of polygonal, equilateral, but not equiangular, shape designed for centerless descaling of rough-drawn or rough-rolled materials, by radial mounting on a rotary multi-tool head, and including lengths, each having a main cutting edge having a straight part and a curved part connecting the main cutting edge to a secondary planing edge, said plate characterized in that it comprises along each main cutting edge two chip-breaking surfaces consisting of separate concave grooves, generated by segments of curves respectively tangent at their lowest point to one and the same directing axis;

• a. the first chip-breaking surface facing the straight part of the main cutting edge, of which the axis directing the surface is parallel with the said edge and forming a cutting angle .alpha..sub.1 ;
• b. the second chip-breaking surface facing the curved part connecting the main cutting edge to the secondary planing edge and having a directing axis perpendicular to the plane bisecting the curved part and forming a cutting angle .alpha..sub.2.