Metal cutting grooving insert for face grooving

10766075 ยท 2020-09-08

Assignee

Inventors

Cpc classification

International classification

Abstract

A grooving insert includes a front surface and an opposite rear surface, a first side surface and an opposite second side surface, and a top surface and an opposite bottom surface. The top surface includes a top front portion and a top rear portion, the top front portion having a cutting edge arranged symmetrically relative to a first plane. The bottom surface is symmetrically arranged in relation to a second plane, the first plane and the second plane forming an angle () of 0.5-5.0 relative to each other.

Claims

1. A grooving insert comprising: a front surface and an opposite rear surface; a first side surface and an opposite second side surface; and a top surface and an opposite bottom surface, the top surface including a top front portion and a top rear portion, the top front portion having a rake face and a cutting edge, the cutting edge being at least partly formed in an intersection between the rake face and the front surface, the cutting edge extending continuously or substantially continuously between a first end point and a second end point, the cutting edge being arranged symmetrically or substantially symmetrically relative to a first plane, wherein the first plane intersects a mid-point of the cutting edge and intersects the rear surface, the top rear portion having a top support surface and the bottom surface having a bottom support surface, wherein the bottom surface is symmetrically or substantially symmetrically arranged in relation to a second plane, the second plane intersecting the front surface and the rear surface, and wherein the first plane and the second plane form an angle of 0.5-5.0 relative to each other in a top view.

2. The grooving insert according to claim 1, wherein a distance from the bottom surface to a reference plane, is increasing away from the front surface towards the rear surface, where at least 50% of the cutting edge, the first end point and the second end point are located in the reference plane, and wherein the reference plane is perpendicular to the first plane.

3. The grooving insert according to claim 1, wherein the cutting edge includes a first distal edge portion adjacent to the first side surface, and a second distal edge portion adjacent to the second side surface, wherein the first and second distal edge portions are the most distal portions of the cutting edge in relation to the first plane, wherein a third plane, parallel to the first plane, intersects the first distal edge portion, wherein a fourth plane, parallel to the first plane, intersects the second distal edge portion, and wherein a distance from the fourth plane to the bottom support surface increases towards the rear surface.

4. The grooving insert according to claim 1, wherein the bottom surface includes a first groove symmetrically arranged in relation to the second plane and extending from the front surface to the rear surface.

5. The grooving insert according to claim 1, wherein the first side surface includes a first clearance surface adjacent to a first portion of the cutting edge, wherein the first clearance surface forms a first clearance angle in relation to the third plane, wherein the second side surface includes a second clearance surface adjacent to a second portion of the cutting edge, wherein the second clearance surface forms a second clearance angle in relation to the third plane, the second clearance angle being larger than the first clearance angle.

6. The grooving insert according to claim 1, wherein the first side surface includes a first clearance surface adjacent to a first portion of the cutting edge and the second side surface includes a second clearance surface adjacent to a second portion of the cutting edge, and wherein lower boundary lines of each of the first and second clearance surfaces and the bottom surface are spaced apart, an area of the second clearance surface being greater than an area of the first clearance surface.

7. The grooving insert according to claim 1, wherein a width of the bottom surface that is perpendicular to the second plane, decreases away from the front surface.

8. The grooving insert according to claim 1, wherein the rear surface includes a first rear support surface adjacent to the first side surface and a second rear support surface adjacent to the second side surface, and a second groove extending from the top surface towards the bottom surface and extending between the first rear support surface and the second rear support surface.

9. The grooving insert according to claim 1, wherein the grooving insert has exactly one cutting edge.

10. The grooving insert according to claim 1, wherein the top rear portion includes a central structure symmetrically or substantially symmetrically arranged in relation to a sixth plane, wherein the sixth plane intersects the front surface and the rear surface, wherein the first plane and the sixth plane form an angle of 0.5-5.0 relative to each other, wherein the angle between the first and sixth planes and angle between the first plane and second planes are equally large, wherein the second plane and the sixth plane are parallel and spaced apart, and wherein a distance from the second side surface to the sixth plane is shorter than a distance from the second side surface to the second plane.

11. The grooving insert according to claim 10, wherein a central structure of the top rear portion is a third groove, wherein the third groove is spaced apart in relation to each of the first and second side surfaces, wherein the sixth plane intersects the cutting edge at an intersection point which is spaced apart from the mid-point of the cutting edge, and wherein a distance from the second side surface to the intersection point is shorter than a distance from the second side surface to the mid-point of the cutting edge.

12. The grooving insert according to claim 1, wherein the top front portion is wider than the top rear portion, where the widths are measured perpendicular to the second plane.

13. The grooving insert according to claim 1, wherein the top support surface includes a first top support surface adjacent to the first side surface, and a second top support surface adjacent to the second side surface, wherein the third groove extends between the first and second top support surfaces, wherein the bottom support surface includes a first bottom support surface adjacent to the first side surface, and a second bottom support surface adjacent to the second side surface, wherein the first groove extends between the first and second bottom support surfaces, and wherein a width of the second top support surface increases towards the rear surface, the width of the second top support surface being measured in a plane perpendicular to the first plane.

14. The grooving insert according to claim 13, wherein a width of each of the first top support surface, the first bottom support surface, and the second bottom support surface decreases towards the rear surface, where the widths are measured in planes perpendicular to the first plane.

15. A grooving tool comprising: a grooving insert according to claim 1; and a face grooving tool body, the face grooving tool body having a blade portion, the blade portion including a top surface, an opposite bottom surface, a first side surface and an opposite second side surface, a front end and an opposite rear end, a longitudinal axis of the blade portion coinciding with a primary cutting feed direction of the blade portion, an insert seat in which the grooving insert is seated, wherein the insert seat opens in the front end, the insert seat including an upper clamping surface formed in the upper blade portion in contact with the top support surface, the bottom surface including a bottom support surface, an opposite lower support surface formed in the lower blade portion in contact with the bottom support surface, and a rear support surface in contact with the rear surface, wherein a lower support surface central axis forms an angle 1-45 relative to the longitudinal axis in a side view such that the lower support surface central axis and the longitudinal axis in a side view intersect forward of the front end, the first side surface being curved around a first side surface axis of curvature, wherein the first side surface axis of curvature is parallel to the longitudinal axis, the second side surface being curved around the second side surface axis of curvature, wherein the first side surface of the blade portion and the first side surface of the grooving insert faces the first and second side surface axes of curvature, and wherein the second plane intersects the first side surface axis of curvature rearwards of the front surface of the grooving insert.

Description

DESCRIPTION OF THE DRAWINGS

(1) The present invention will now be explained in more detail by a description of different embodiments of the invention and by reference to the accompanying drawings.

(2) FIG. 1 is a perspective view of a face grooving tool comprising a first face grooving tool body and a grooving insert according to a first embodiment.

(3) FIG. 2 is a front view of the face grooving tool in FIG. 1.

(4) FIG. 3 is a first side view of the face grooving tool in FIG. 1.

(5) FIG. 4 is a top view of the face grooving tool in FIG. 1.

(6) FIG. 5 is a second side view of the face grooving tool in FIG. 1.

(7) FIG. 6 is a top view of the face grooving tool in FIG. 1 and a metal work piece.

(8) FIG. 7 is a top view of the face grooving tool body in FIG. 1.

(9) FIG. 8 is a perspective view of the face grooving tool body in FIG. 1.

(10) FIG. 9 is a front view of the face grooving tool body in FIG. 1.

(11) FIG. 10 is a mirror view of the face grooving tool body in FIG. 5.

(12) FIG. 11 is a perspective view of a second face grooving tool body.

(13) FIG. 12 is a perspective view of a third face grooving tool body.

(14) FIG. 13 is a perspective view of a fourth face grooving tool body.

(15) FIG. 14 is a perspective view of fifth face grooving tool body.

(16) FIG. 15 is a front view of the face grooving tool body in FIG. 14.

(17) FIG. 16 is a top view of a face grooving tool body in FIG. 14.

(18) FIG. 17 is a perspective view of the grooving insert in FIG. 1.

(19) FIG. 18 is a front view of the grooving insert in FIG. 17.

(20) FIG. 19 is a rear view of the grooving insert in FIG. 17.

(21) FIG. 20 is a top view of the grooving insert in FIG. 17.

(22) FIG. 21 is a bottom view of the grooving insert in FIG. 17.

(23) FIG. 22 is a first side view of the grooving insert in FIG. 17.

(24) FIG. 23 is a second side view of the grooving insert in FIG. 17.

(25) FIG. 24 is a perspective view of a grooving insert according to a second embodiment.

(26) FIG. 25 is a front view of the grooving insert in FIG. 24.

(27) FIG. 26 is a rear view of the grooving insert in FIG. 24.

(28) FIG. 27 is a top view of the grooving insert in FIG. 24.

(29) FIG. 28 is a bottom view of the grooving insert in FIG. 24.

(30) FIG. 29 is a first side view of the grooving insert in FIG. 24.

(31) FIG. 30 is a second side view of the grooving insert in FIG. 24.

(32) All drawings or figures have been drawn to scale.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

(33) Reference is made to FIG. 1, which show a face grooving tool 50 comprising a first face grooving tool body 51 and a grooving insert 1 according to a first embodiment positioned in an insert seat. The grooving insert 1 is made from a harder material, e.g. cemented carbide, than the face grooving tool body 51, which is made from steel. The face grooving tool body 51 comprises a blade portion 52. The blade portion 52 comprises a top surface 53, an opposite bottom surface 54, a first side surface 55 and an opposite second side surface (not shown), a front end 57 and an opposite rear end 58. A longitudinal axis of the blade portion 52 coincides with a primary cutting feed direction F1 of the blade portion 52. The primary cutting feed direction F1, which defines a front or forward direction of the face grooving tool 50, is the direction in which the face grooving tool 50 moves during cutting or machining relative to a rotating metal work piece, in which a circular groove is formed. The circular groove has a width which corresponds to the width of a main cutting edge of the grooving insert 1 of the face grooving tool 50. An upper blade portion 61 associated with the top surface 53 and a lower blade portion 62 associated with the bottom surface 54 are separated by a slit 59 extending from the front end 57 to a rear slit end 60. The upper blade portion and lower blade portions 61, 62 are permanently connected rearward of the rear slit end 60. The slit 59 intersects, or opens into, the first and second side surfaces 55, 56. The slit 59 comprises an insert seat 63 for the grooving insert 1 which opens in the front end 57. The face grooving tool body 51 comprises a clamping portion 83, in the form of a shank having a square shaped cross section, extending in a direction parallel to the longitudinal axis A1. The blade portion 52 and the clamping portion 83 are permanently connected, more precisely; they are one singular unit formed from a singular piece of metal.

(34) Reference is now made to FIG. 2. The second side surface 56 of is curved around a second side surface axis of curvature A4 parallel to the longitudinal axis A1 of the blade portion, such that all parts of the second side surface 56 has a constant distance to the second side surface axis of curvature A4. The first side surface 55 is curved around a first side surface axis of curvature A3, such that all parts of the first side surface 55 has a constant distance to the first side surface axis of curvature A3. The first and second side surface axes of curvature A3, A4 are parallel to the longitudinal axis A1 of the blade portion. The first side surface 55 is facing the first and second side surface axes of curvature A3, A4. A distance from the first side surface 55 to the first side surface axis of curvature A3 is shorter than a distance from the first side surface 55 to the second side surface axis of curvature A4.

(35) The longitudinal center axis A5 of the clamping portion is parallel to the longitudinal axis A1.

(36) The bottom surface 90 of the clamping portion 83 is located in a plane parallel to P5, where P5 is a reference plane in which at least 50% of the cutting edge is located.

(37) The longitudinal axis A1 is located in the reference plane P5.

(38) A distance from the bottom surface 90 of the clamping portion 83 to the top surface 53 of the blade portion 52 is greater than a distance from the bottom surface 90 of the clamping portion 83 to the top surface 89 of the clamping portion 83.

(39) Reference is now made to FIG. 3. It can be seen that the longitudinal axis A1 of the blade portion coincides a primary cutting feed direction F1 of the blade portion. The blade portion 52 comprises a fluid channel, comprising a first fluid channel portion 87 in the lower blade portion 62 having an outlet opening into the slit 59, and a second fluid channel portion 88 in the upper blade portion 61 having an inlet opening into the slit 59. The second fluid channel portion 88 is a through hole. The first and second fluid channel portions 87, 88 extend along a common axis, and extend between the first and second side surfaces. In FIG. 3, the second side surface 56 is facing the viewer. The bottom surface 90 of the clamping portion 83 is located in a plane parallel to the longitudinal axis A1 of the blade portion.

(40) Reference is now made to FIG. 4. The first and second side surface axes of curvature A3, A4 are parallel to the longitudinal center axis A5 of the clamping portion 83 and the longitudinal axis A1 of the blade portion, which coincides with a primary cutting feed direction F1 of the blade portion. Distances from the first side surface 55 to the first and second side surface axes of curvature A3, A5 is greater than distances from the second side surface 56 to the first and second side surface axes of curvature A3, A4.

(41) Reference is now made to FIG. 5. A lower support surface central axis A7 forms an angle 1-45, in FIG. 5 the angle is 15-25, relative to the longitudinal axis A1 in a side view, as shown in FIG. 5, such that the lower support surface central axis A7 and the longitudinal axis A1 in a side view converge forward of the front end 57. The lower support surface central axis A7 forms an identical angle relative to the longitudinal center axis A5 of the clamping portion 83.

(42) The lower support surface is a support surface for the grooving insert 1 located in the insert seat. In FIG. 5, the first side surface 55 is facing the viewer. The lower support surface central axis A7 intersects a plane comprising the bottom surface 90 of the clamping portion 83 rearward of the front end 57.

(43) Reference is now made to FIG. 6. A metal work piece 93 is rotatable around a rotation axis A8. When the face grooving tool is moved relative in a primary cutting feed direction F1 of the blade portion, a circular groove 94 is formed in the metal work piece 93, having a center thereof coinciding with the rotation axis A8 of the metal work piece 93. The width of the circular groove 98, i.e. the distance between a radially inner and a radially outer side wall of the circular groove 98, corresponds to the width of the cutting edge of the grooving insert mounted in the insert seat of the face grooving tool body. A distance from the first side surface 55 to the first side surface axis of curvature is equal or greater than a distance from the rotation axis A8 of the metal work piece 93 to the radially inner side wall of the circular groove 98.

(44) A distance from the second side surface 56 to the second side surface axis of curvature is equal or smaller than a distance from the rotation axis A8 of the metal work piece 93 to the radially outer side wall of the circular groove 98. The depth of the circular groove 94, i.e. the extension parallel to the rotation axis A8 of the metal work piece 93, is equal to or smaller than a distance, measured along the longitudinal axis of the blade portion, from the rear end of the blade portion to the active cutting edge of the grooving insert. When machining the circular groove 94, the first side surface of the grooving insert is facing the radially inner wall surface of the circular groove 94, and the second side surface of the grooving insert is facing the radially outer wall surface of the circular groove 94.

(45) Reference is now made to FIG. 7. Here it is shown that the lower support surface central axis A7 in a top view forms an angle 0.5-5.0, in FIG. 7 the angle is 2-3, relative to the longitudinal axis A1 of the blade portion.

(46) Reference is now made to FIG. 8, showing a portion of the face grooving tool body 51, where it is shown that the lower support surface central axis A7 and the longitudinal axis A1 converge forward of the front end 57. The slit comprises a slit portion 68, wherein at least a major portion of the slit portion 68 is curved around an axis A6, which intersect the lower blade portion, which axis A6 is substantially perpendicular to the longitudinal axis A1 of the blade portion. The first side surface 55 is shown.

(47) Reference is now made to FIG. 9, which show that the insert seat comprises an upper clamping surface 64 formed in the upper blade portion, an opposite lower support surface 65 formed in the lower blade portion, and a rear support surface 76 formed in the lower blade portion. The insert seat extends between the first and second side surfaces 55, 56 of the blade portion. As can also be seen in e.g. FIG. 8, the upper clamping surface 64, the lower support surface 65 and the rear support surface 76 each comprise a central structure, in the form of a central ridge, separating non-coplanar surfaces. A width of the lower blade portion 62, measured as the distance between the first and second side surfaces 55, 56 of the lower blade portion 62, is decreasing from the lower support surface 65 towards the bottom surface 54 of the lower blade portion 62.

(48) Reference is now made to FIG. 10, which is a mirror view of FIG. 5. The blade portion 52 comprises a top surface 53, an opposite bottom surface 54, a first side surface 55 and an opposite second side surface, a front end 57 and an opposite rear end 58. A distance between the top and bottom surfaces 53, 54 is increasing from the front end 59 towards the rear end 58 up to at least the rear end of the slit portion 59. An upper blade portion 61 associated with the top surface 53 and a lower blade portion 62 associated with the bottom surface 54, are separated by a slit extending from the front end 57 to a rear slit end 60. The slit comprises, adjacent to the front end 57, an insert seat 63 for a grooving insert. The insert seat 63 comprises an upper clamping surface 64 formed in the upper blade portion 61, an opposite lower support surface 65 formed in the lower blade portion 62, and a rear support surface 76 formed in the lower blade portion 62. The lower support surface 65 extends a greater distance from the rear end 58 than the distance the upper clamping surface 64 extends from the rear end 58. The slit 59 comprises a key hole 66, and a slit portion 68 extending between a slit portion front end 69 and a slit portion rear end 70. The longitudinal axis A1 intersects the key hole 66. The longitudinal axis A1 intersects the upper clamping surface 64. The slit portion 68 is located between the rear slit end 60 and the key hole 66. A slit gap intersecting a center of the key hole 66 is greater than a slit gap at the slit portion 68. The key hole 66 is located between the slit portion 68 and the insert seat 63. The key hole 66 comprises a first and a second concave surface 77, 78, formed in the upper blade portion 61, and connected by a first flat surface 79. The key hole 66 further comprises a third and a fourth concave surface 80, 81, formed in the lower blade portion 62, and connected by a second flat surface 82. The key hole 66 comprises substantially opposite openings towards the insert seat 63 and towards the slit portion 68, respectively. In other words, the key hole is part of the slit. The slit comprises a connecting portion 67, connecting the key hole 66 and the insert seat 63, intersecting the insert seat 63 between the rear support surface 76 and the upper clamping surface 64. A second connecting portion 91, convex in side view, is located between and connecting the key hole 66 and the slit portion 68. At least a major portion of the slit portion 68 is curved or substantially curved around an axis A6, intersecting the lower blade portion 62, at a radius of curvature 92. The slit portion 68 or a major portion of the slit portion 68 is concave or substantially concave in a side view as seen in e.g. FIG. 10. The radius of curvature 92 is substantially equal to, i.e. 75%-125%, of a shortest distance between the slit portion front end 69 and the slit portion rear end 70. The length of the slit portion 68 as defined as a shortest distance between the slit portion front end 69 and the slit portion rear end 70 is greater than the length of the key hole 66. The slit portion 68 is located between the rear slit end 60 and the insert seat 63. A distance 71 from the bottom surface 54 to the rear slit end 60 is greater than a distance 72 from the bottom surface 54 to the slit portion 68 front end 69 or to the second connecting portion 91. The slit portion 68 has a constant or substantially constant slit gap. The first side surface 55 of the lower blade portion 62 is formed as a continuous surface which runs uninterrupted from the slit to the bottom surface 54. A distance 73 from the bottom surface 54 to a lowest point of the insert seat 63 is smaller than a distance 75 from the bottom surface 54 to the key hole 66. A distance from rear support surface 76 to the rear slit end 60 is greater than a distance from rear support surface 76 to the front end 57 of the slit portion 68. The rear slit end 60 preferably comprises a border surface in the shape of a circular arc.

(49) Reference is now made to FIG. 11, which is a perspective view of a second face grooving tool body. The only substantial difference compared to the first face grooving tool body is the position of the blade portion relative to the clamping portion 83, and the shape of the clamping portion 83. In the second embodiment, the clamping portion 83 is circular in a cross section, and comprises 4 screw holes. The face grooving tool body is suitable for internal face grooving, i.e. face grooving inside a hole in a metal work piece.

(50) Reference is now made to FIG. 12, which is a perspective view of a third face grooving tool body. The only substantial difference compared to the first face grooving tool body is the shape of the clamping portion 83. For the third face grooving tool body, the clamping portion 83 is circular in a cross section, and comprises 4 screw holes.

(51) Reference is now made to FIG. 13, which is a perspective view of a forth face grooving tool body. The only substantial difference compared to the first face grooving tool body is the shape of the second side surface 56. More specifically, a rear portion of lower blade portion 56 is widened, rearward of the key hole 66. Thus, the mechanical strength of the lower blade portion 56 is further increased.

(52) Reference is now made to FIGS. 14-16 which shows a fifth face grooving tool body. The only substantial difference compared to the first face grooving tool body is that the longitudinal center axis A5 of the clamping portion is perpendicular to the longitudinal axis A1. The blade portion, including the first and second side surfaces 55, 56, is identical to the blade portion according to the first embodiment.

(53) Reference is now made to FIGS. 17-23, which show the grooving insert 1, according to a first embodiment, which is part of the face grooving tool in FIG. 1. The grooving insert 1 comprises a front surface 4 and an opposite rear surface 5, a first side surface 6 and an opposite second side surface 7, a top surface 2 and an opposite bottom surface 3.

(54) An area of the top surface 2 in a top view is greater than an area of the bottom surface 3 in a bottom view. The top surface 2 comprises a top front portion 9 and a top rear portion 10. The top front portion 9 comprises a rake face 11 and a cutting edge 8. The cutting edge 8 is partly formed in an intersection between the rake face 11 and the front surface 4, and partly formed in an intersection between the rake face 11 and the first and second side surface 6, 7, respectively. The top front portion 9 comprises a non-planar chip forming surface or a chip forming structure. The front surface 4 is a clearance surface when the face grooving tool in which the grooving insert 1 is mounted is moved in a primary cutting feed direction. The cutting edge 8 extends continuously between a first end point 12 and a second end point 13. The first end point 12 is located in an intersection between the first side surface 6 and the top front portion 9. The second end point 13 is located in an intersection between the second side surface 7 and the top front portion 9. The cutting edge 8, the top front portion 9 and the rake face 11 are arranged symmetrically relative to a first plane P1, which first plane P1 intersects a mid-point 14 of the cutting edge 8 and intersects the rear surface 5.

(55) As can be seen in e.g. FIG. 20, the cutting edge 8 comprises a main cutting edge portion extending perpendicular to the first plane P1, which is 1.0-20.0 mm, in FIG. 20 the main cutting edge portion is 2.0-4.0 mm.

(56) The main cutting edge portion is connected to the first portion 23 of the cutting edge 8 through a first arc shaped corner cutting edge. The first arc shaped corner cutting edge comprises a first distal edge portion 17.

(57) In a similar manner, the main cutting edge portion is connected to the second portion 24 of the cutting edge 8 through a second arc shaped corner cutting edge. The second arc shaped corner cutting edge comprises a second distal edge portion 17.

(58) The top rear portion 10 comprises a top support surface 15, 16. The bottom surface 3 comprising a bottom support surface 31, 32. At least a major portion of the bottom surface 3 is symmetrically or substantially symmetrically arranged in relation to a second plane P2, which second plane P2 intersects the front surface 4 and the rear surface 5. In FIG. 21, the front end of the bottom surface 3 is not perfectly symmetrically arranged in relation to the second plane P2, because the bottom surface 3 front end is perpendicular to the first plane P1.

(59) The first plane P1 and the second plane P2 forms an angle of 0.5-5.0 relative to each other, which angle in FIGS. 17-23 is 2.5. A distance 33 from the bottom surface 3 to a reference plane P5, is increasing away from the front surface 4 towards the rear surface 5. At least 50% of the cutting edge 8, the first end point 12 and the second end point 13 are located in the reference plane P5. The reference plane P5 is perpendicular to the first plane P1. A minor portion of the cutting edge 8, comprising the mid-point 14, is spaced apart from the reference plane P5. The minor portion is symmetrically arranged relative to the mid-point 14, and is concave in a front view, as seen in FIG. 18.

(60) As seen in FIG. 22 and FIG. 23, in a side view the reference plane P5 and the bottom surface 3 forms an angle relative to each other, which angle is preferably 10-30.

(61) The cutting edge 8 comprises the first distal edge portion 17, adjacent to the first side surface 6, and the second distal edge portion 18, adjacent to the second side surface 7.

(62) The first and second distal edge portions 17, 18 are the most distal portions of the cutting edge 8 in relation to the first plane P1. When the grooving insert 1 is mounted in the insert seat of the face grooving tool body, and the blade portion is moved in the primary cutting feed direction, the first and second distal edge portions 17, 18 are the surface generating portions of the radially inner and outer side walls of the circular groove formed.

(63) Thus, as can be seen in FIG. 6, the width of the circular groove 98, i.e. the distance between a radially inner and a radially outer side wall of the circular groove 98, corresponds to the distance between the first and second distal edge portions 17, 18.

(64) A third plane P3, parallel to the first plane P1, intersects the first distal edge portion 17. A fourth plane P4, parallel to the first plane P1, intersects the second distal edge portion 18.

(65) A distance 19 from the fourth plane P4 to the bottom support surface 31, 32 is increasing from the front surface 4 towards the rear surface 5.

(66) The bottom surface 3 comprises a first groove 20 symmetrically arranged in relation to the second plane P2 and extending from the front surface 4 to the rear surface 5.

(67) The extension of the first groove 20 corresponds to the extension of the lower support surface 65 central ridge of the insert seat 63. The first side surface 6 comprises a first clearance surface 21 adjacent to a first portion 23 of the cutting edge 8.

(68) The first clearance surface 21 forms a first clearance angle in relation to the third plane P3. The second side surface 7 comprises a second clearance surface 22 adjacent to a second portion 24 of the cutting edge 8. The second clearance surface 22 forms a second clearance angle in relation to the third plane P3. The second clearance angle is larger than the first clearance angle . Each of the first and second clearance surfaces 21, 22 and the bottom surface 3 are spaced apart.

(69) An area of the second clearance surface 22 is greater than an area of the first clearance surface 21, as seen in FIGS. 22-23.

(70) A width 25 of the bottom surface 3, perpendicular to the second plane P2, is decreasing away from the front surface 4.

(71) The rear surface 5 comprises a first rear support surface 27 adjacent to the first side surface 6 and a second rear support surface 28 adjacent to the second side surface 7. The rear surface 5 further comprises a second groove 26 extending from the top surface 2 to the bottom surface 3 and extending between the first rear support surface 27 and the second rear support surface 28. An area of the first rear support surface 27 is smaller than an area of the second rear support surface 28.

(72) The grooving insert 1 comprises exactly one cutting edge.

(73) Adjacent the rear surface 5 no cutting edge is formed.

(74) The top rear portion 10 comprises a third groove 29 symmetrically or substantially symmetrically arranged in relation to a sixth plane P6. The sixth plane P6 intersects the front surface 4 and the rear surface 5.

(75) The first plane P1 and the sixth plane P6 form an angle of 0.5-5.0 relative to each other. Angle and angle are equally large. The second plane P2 and the sixth plane P6 are parallel and spaced apart. A distance from the second side surface 7 to the sixth plane P6 is shorter than a distance from the second side surface 7 to the second plane P2.

(76) The third groove 29 is spaced apart in relation to each of the first and second side surfaces 6, 7. An extension of the third groove 29 intersects the cutting edge 8 at an intersection point 30. The intersection point 30 is spaced apart from the mid-point 14 of the cutting edge 8. A distance from the second side surface 7 to the intersection point 30 is shorter than a distance from the second side surface 7 to the mid-point 14 of the cutting edge 8. The sixth plane P6 intersects the cutting edge 8 at the intersection point 30. The third groove 29 has a main extension along the sixth plane P6.

(77) The top front portion 9 of the grooving insert 1 is wider than the top rear portion 10, where the widths are measured perpendicular to the second plane P2.

(78) The top support surface 15, 16 comprises a first top support surface 15, adjacent to the first side surface 6, and a second top support surface 16, adjacent to the second side surface 7.

(79) The third groove 29 extends between the first and second top support surfaces 15, 16.

(80) The bottom support surface 31, 32 comprises a first bottom support surface 31, adjacent to the first side surface 6, and a second bottom support surface 32, adjacent to the second side surface 7. The first groove 20 extends between the first and second bottom support surfaces 31, 32.

(81) A width of the second top support surface 16 is increasing towards the rear surface 5, where the width of the second top support surface 16 is measured in a plane perpendicular to the first plane P1.

(82) A width each of first top support surface 15, first bottom support surface 31, and the second bottom support surface 32 is decreasing towards the rear surface 5, where the width of the second top support surface 16 is measured in a plane perpendicular to the first plane P1.

(83) Reference is now made to FIGS. 24-30, which show a grooving insert 1 according to a second embodiment which is mountable in the face grooving tool body in FIG. 1. The grooving insert 1 differs from the grooving insert shown in FIGS. 17-23 only with regards to the top front portion 9, the cutting edge 8, the front surface 4, and the first and second clearance surfaces 21, 22.

(84) The cutting edge 8 of the second grooving insert 1 is shaped as, or extends along, a circular arc, which is best seen in FIG. 27. More specifically, the cutting edge is shaped as a major arc, which subtends an angle greater than 180 but less than 360. The angle for the second grooving insert 1 is 190-250.

(85) In other words, the angle between the first end point 12 and the second end point 13 is 190-250.

(86) The cutting edge 8 of the second grooving insert 1 is completely located in the reference plane P5, which is perpendicular to the first plane P1.

(87) The first and second distal edge portions 17, 18 of the second grooving insert 1 is located relatively closer to the rear surface 5, compared to the first and second distal edge portions of the first grooving insert.

(88) The first and second clearance surfaces 21, 22 of the second grooving insert 1 has upper portions, adjacent to the cutting edge 8 which corresponds to the circular arc shape of the cutting edge.

(89) As for the first grooving insert, the first side surface 6 comprises a first clearance surface 21 adjacent to a first portion 23 of the cutting edge 8 forming a first clearance angle in relation to the third plane P3. Likewise, the second side surface 7 comprises a second clearance surface 22 adjacent to a second portion 24 of the cutting edge 8. The second clearance surface 22 forms a second clearance angle in relation to the third plane P3. The second clearance angle is larger than the first clearance angle . Each of the first and second clearance surfaces 21, 22 and the bottom surface 3 are spaced apart.

(90) An area of the second clearance surface 22 is greater than an area of the first clearance surface 21, as seen in FIGS. 29-30.

(91) Regardless of it is the grooving insert 1 according to a first embodiment or if it is the grooving insert 1 according to a second embodiment which is mounted or positioned in the insert seat 63 of the face grooving tool body 51, the top support surface 15, 16 of the grooving insert 1 is in contact with the upper clamping surface 64, the bottom support surface 31, 32 of the grooving insert 1 is in contact with the lower support surface 65, and the rear support surface 27, 28 of the grooving insert 1 is in contact with the insert seat 63 rear support surface 76. In a corresponding manner, the first side surface 55 of the blade portion 52 is adjacent to the first side surface 6 of the grooving insert 1, and the second side surface 56 of the blade portion 52 is adjacent to the second side surface 7 of the grooving insert 1. Formulated differently, the first side surface 55 of the blade portion 52 and the first side surface 6 of the grooving insert 1 are facing the same direction, and the second side surface 56 of the blade portion 52 and the second side surface 7 of the grooving insert 1 are both facing an opposite direction.

(92) In the present application, the use of terms such as including is open-ended and is intended to have the same meaning as terms such as comprising and not preclude the presence of other structure, material, or acts. Similarly, though the use of terms such as can or may is intended to be open-ended and to reflect that structure, material, or acts are not necessary, the failure to use such terms is not intended to reflect that structure, material, or acts are essential. To the extent that structure, material, or acts are presently considered to be essential, they are identified as such. Terms such as upper, lower, top, bottom, forward and rear refer to features as shown in the current drawings and as perceived by the skilled person.