Patent ID: 8776649
Filing Date: 2014-07-15
Classification: B23B,Y10T

Abstract:
1. A turning insert formed for chip-cutting metal machining of a workpiece that rotates in a direction of rotation at a first speed of rotation around a workpiece axis, the turning insert comprising: a front surface; an envelope surface; and a circular cutting edge located where the front surface meets the envelope surface, the cutting edge extending around the front surface and lying in a plane that forms an acute angle α with the envelope surface, a tool axis extending through the turning insert in a normal direction in respect of the plane, and the turning insert, during the chip-cutting metal machining, being formed to rotate around the tool axis at a second speed of rotation, wherein the envelope surface forms a chip surface and is arranged to meet chips formed in the chip-cutting metal machining, and the chip surface comprises chip breaking means, wherein the chip surface comprises a circumferential first portion that borders on the cutting edge and a circumferential second portion that borders on the circumferential first portion, wherein the circumferential first portion has one of a concave shape and a conical shape as seen in a cross-sectional plane including the tool axis, and wherein at least a portion of the envelope surface of the circumferential second portion projects radially outward past at least a portion of the envelope surface of the circumferential first portion.