A cutting insert having two end portions and an intermediate portion extending longitudinally between the two end portions. The intermediate portion has N side surfaces and N primary cutting edges. The N primary cutting edges are formed at the intersection of adjacent side surfaces. Each one of the N primary cutting edges extends from one end portion to the other end portion. At least N secondary cutting edges formed on at least one of the two end portions. A cutting corner is formed between a primary cutting edge and a secondary cutting edge. Each secondary cutting edge extending away from the cutting corner in a direction generally away from the intermediate portion.
1. A cutting insert comprising:
two end portions and an intermediate portion extending therebetween, the cutting insert having an insert axis (A) which traverses the cutting insert in a first longitudinal direction between the two end portions;
a number of side surfaces equal to an integer number N and N primary cutting edges, the N primary cutting edges being formed at the intersection of adjacent side surfaces, each one of the N primary cutting edges extending between the two end portions;
at least N secondary cutting edges formed on at least one of the two end portions, the at least one of the two end portions extending along said first longitudinal direction;
at least N cutting corners, each cutting corner being formed between a primary cutting edge and a secondary cutting edge, each secondary cutting edge extending away from an associated cutting corner in a direction generally away from the intermediate portion and along said first longitudinal direction.
2. A cutting insert having a longitudinal insert axis (A), an intermediate portion and two end portions connected to opposite ends of the intermediate portion, the in intermediate portion and the end portions extending along the longitudinal insert axis (A), a number of side surfaces equal to an integer number N, N primary cutting edges formed at the intersection of adjacent side surfaces and extending between the end portions, at least N secondary cutting edges formed on a first end portion, each of the N secondary cutting edges being connected to an associated primary cutting edge via a cutting corner, wherein:
the first end portion has an axially outermost surface that is axially spaced apart from the intermediate portion along the longitudinal insert axis (A); and
in a top view of the cutting insert, at least one of the N secondary cutting edges extends from an associated cutting corner in a direction of said axially outermost surface.
3. The cutting insert according to claim 2 , wherein each primary cutting edge is provided with a chip control element.
4. The cutting insert according to claim 3 , wherein the chip control element is a groove.
5. The cutting insert according to claim 4 , wherein the groove has a U-shaped profile.
6. The cutting insert according to claim 4 , wherein the groove has a non-symmetric V-shaped profile.
7. The cutting insert according to claim 2 , wherein at least one end portion comprises a peripheral end surface extending from the N side surfaces to an end face.
8. The cutting insert according to claim 7 , wherein the end face is provided with a recess.
9. The cutting insert according to claim 7 , wherein the peripheral end surface extends from the N side surfaces generally longitudinally away from the intermediate portion and towards the insert axis (A).
10. The cutting insert according to claim 7 , wherein the peripheral end surface comprises N sub-peripheral end surfaces.
11. The cutting insert according to claim 10 , wherein each sub-peripheral end surface is divided into two portions, a leading portion and a trailing portion.
12. The cutting insert according to claim 11 , wherein the leading portion of a sub-peripheral end surface and an adjacent chip control element meet at a secondary cutting edge.
13. The cutting insert according to claim 2 , wherein at least one of the N cutting corners is chamfered.
14. The cutting insert according to claim 2 , wherein at least one of the N secondary cutting edges is curved.
15. The cutting insert according to claim 2 , wherein the cutting insert N-fold rotational symmetry about the insert axis (A).
16. The cutting insert according to claim 2 , wherein N is at least four.
17. The cutting insert according to claim 2 , wherein N is equal to 4.
18. The cutting insert according to claim 2 , wherein the primary cutting edges are substantially straight and are substantially parallel to the insert axis (A).
19. A cutting insert having a longitudinal insert axis (A) and comprising:
an intermediate portion and two end portions connected to opposite ends of the intermediate portion, the intermediate portion and the end portions extending along the longitudinal axis (A);
a number of side surfaces equal to an integer number N and N primary cutting edges formed at the intersection of adjacent side surfaces, each one of the N primary cutting edges extending between the two end portions;
at least N secondary cutting edges formed on a first end portion, said first end portion having an axially outermost surface that is axially spaced apart from the intermediate portion along the to longitudinal insert axis (A);
at least N cutting corners, each cutting corner being formed between a primary cutting edge and a secondary cutting edge, wherein, in a top view of the cutting insert, the secondary cutting edge from an associated cutting corner in a direction of said axially outermost surface.