Drill cutting insert

A drill cutting insert, comprising:

• a top surface, a bottom surface, and a circumferential side face connecting said top surface with said bottom surface;
• a cutting edge formed at a transition between said side face and said top surface, said cutting edge having n identical cutting corners and n identical partial cutting edges, each extending between two respective said cutting corners, where n {3, 4};
• each of said n partial cutting edges having:
• a main cutting edge adjoining a first cutting corner, said main cutting edge being straight in a top plan view onto said top surface;
• a secondary cutting edge adjoining another cutting corner, said secondary cutting edge being straight in a top plan view onto said top surface;
• a transition portion, by way of which said main cutting edge and said secondary cutting edge merge into one another, said transition portion having a convex portion adjoining said main cutting edge and a concave portion adjoining said secondary cutting edge;
• and
• said main cutting edge and said secondary cutting edge enclosing an angle α<180° with one another on an outside in a top view onto said top surface.

A drilling tool, comprising:

• a basic body formed for rotation about a longitudinal axis;
• at least one exchangeable inner cutting insert and an exchangeable outer cutting insert mounted on said basic body farther outside in a radial direction on said basic body;
• said inner and outer cutting inserts being identical cutting inserts and each having at least one partial cutting edge that projects beyond said basic body in an axial direction, each of said projecting partial cutting edges being identical, extending between two cutting corners, and each having:
• a straight main cutting edge adjoining a first cutting corner;
• a straight secondary cutting edge adjoining a second cutting corner;
• and
• a transition portion by way of which said main cutting edge and said secondary cutting edge merge into one another, said transition portion having a convex portion adjoining said main cutting edge and a concave portion adjoining said secondary cutting edge;
• wherein, for each of said inner and outer cutting inserts, said main cutting edge is arranged at a greater distance from the longitudinal axis in the radial direction than said secondary cutting edge;
• wherein said inner cutting insert is arranged with said main cutting edge thereof axially in front of said secondary cutting edge and is aligned with a region thereof that is distanced farther from the longitudinal axis in the radial direction protrudes farther in the axial direction than a region thereof that is arranged closer to the longitudinal axis in the radial direction;
• and
• wherein said outer cutting insert is arranged with said main cutting edge aligned such that a region thereof that is closer to the longitudinal axis in the radial direction protrudes farther in the axial direction than a region thereof that is distanced farther from the longitudinal axis in the radial direction.