To reduce burrs that may be formed at a corner portion of a machined surface in a face milling process, there is provided a cutting insert that does not tend to form burrs. A milling cutting insert includes cutting edges provided as ridges each defined by an upper or lower face and a side face that intersect each other, the cutting edges including a flat cutting edge. The cutting edge include a major cutting edge provided between adjacent ones of corner portions, the flat cutting edge provided at the corner portion, and a minor cutting edge provided between the major cutting edge and the flat cutting edge. A surface roughness of a side face that is continuous with the major cutting edge is higher than a surface roughness of a side face that is continuous with the minor cutting edge.

A cutting insert for high-efficiency cutting is disclosed. The cutting insert includes an upper surface (110a), a lower surface (HOb), side surfaces (114) and corner side surfaces (116), which connect the side surfaces to each other. A circular opening is formed through the central portions of the upper and lower surfaces. In the cutting insert, cutting edges are formed by respective junctions between one of the upper and lower surfaces and the side surfaces and between one of the upper and lower surfaces and the corner side surfaces. The cutting edges comprise three corner cutting edges (122), six major cutting edges (124), which extend from opposite ends of the corner cutting edges towards the neighbor corner cutting edges, and three minor cutting edges (126), which are connected between the major cutting edges. Furthermore, the cutting edges may be formed on both the upper surface and the lower surface.

A cutting insert includes an upper surface, a lower surface, a side surface, and an upper cutting edge. The upper cutting edge includes a major cutting edge having an outwardly projecting curvilinear shape, and a minor cutting edge having a straight line shape and being continuous with the major cutting edge. The side surface includes a continuous inclined surface with the major cutting edge and is inclined outward from the upper surface to the lower surface with respect to a virtual straight line connecting the respective centers of the upper and lower surfaces. An inclination angle of the inclined surface with respect to a virtual straight line on the side surface increases from a portion of the inclined surface which is continuous with an end portion of the major cutting edge to a portion of the inclined surface which is continuous with a center of the major cutting edge.

A cutting insert includes: a polygonal shaped upper surface; a lower surface; a side surface connected to each of the upper and lower surfaces; and an upper cutting edge located at the intersection of the upper surface and the side surface. The upper surface alternately includes three major corners and three minor corners. The upper cutting edge includes: a corner cutting edge; a minor cutting edge inclined toward the lower surface as separating from the corner cutting edge at a first inclination angle; and a major cutting edge inclined toward the lower surface as separating from the minor cutting edge at a second inclination angle. The corner cutting edge, the minor cutting edge and the major cutting edge are located sequentially from a first major corner to each of first and second minor corners, both of which are adjacent to the first major corner.

A double-sided, indexable cutting insert for a milling cutter includes a first surface, a second surface, and side surfaces. Major cutting edges are defined at an intersection between the first and second surfaces and side surfaces. Minor cutting edges and ramping cutting edges are defined at the intersection between the first and second surfaces and side surfaces. The cutting insert is mounted in a milling cutter having a bottom seating surface formed at an angle with respect to a central, rotational axis of the milling cutter, which provides superior performance for both milling and ramping cutting operations.

In a cutting insert according to an embodiment of the present invention, an upper surface sequentially includes a first rake surface and a second rake surface. The first rake surface being inclined toward the lower surface as going inward from the cutting edge at a first rake angle on a basis of a perpendicular plane perpendicular to a central axis extending between the upper surface and a lower surface. The second rake surface is located more inward than the first rake surface and is inclined toward the lower surface at a second rake angle different from the first rake angle on the basis of the perpendicular plane. An intersecting part of the first rake surface and the second rake surface includes a protruded part located at a highest position in a region of the intersecting part along the second side surface. A cutting tool with the cutting insert, and a method of producing a machined product by using the cutting tool are also provided.

A cutting insert with a first flat and major cutting edges in order in an intersection region of a first side surface and an upper surface, and a second flat and major cutting edges in order in an intersection region of a second side surface and upper surface. The first and second side surfaces include respective first and second chamfered side surfaces, respective first and second corner side surfaces, and respective first and second major side surfaces in order. The intersection region of the second side surface and upper surface includes a first intersection region of the second chamfered side surface and upper surface, and a second intersection region of the second corner side surface and upper surface. The second flat cutting edge is located from the first intersection region to the second intersection region, and has a lowermost portion in the first intersection region in a side view.

In a cutting tool having an indexable cutting insert with three cutting portions, the cutting insert is removably securable to an insert holder by means of a fastener. The cutting insert has two opposing end surfaces with a peripheral side surface extending therebetween. At least one end surface has a central boss protruding therefrom with a raised support surface, and the peripheral side surface has three abutment recesses. In an end view of the cutting insert, each of the three abutment recesses is visible and located inside a first imaginary circle circumscribing the visible central boss. A holding portion of the insert holder has a seating surface with at least one protuberance protruding therefrom. The support surface is in clamping contact with the seating surface, and exactly two of the three abutment recesses are engaged with the at least one protuberance.

A cutting insert includes a body having three vertices, an upper face, a lower face, and six planar flank faces perpendicular to and joining the upper and lower faces. A cutting edge is formed at an intersection between the upper and lower faces and each of the planar flank faces. A triangular-shaped island surrounds a central axis, A, of the cutting insert and is higher in elevation than the upper and lower faces. A tool holder includes a tool holder body having a generally triangular-shaped insert-receiving pocket with a triangular-shaped recess that is substantially identical in shape to the triangular-shaped island of the cutting insert that interacts with the island to properly locate and prevent rotation of the cutting insert when mounted in the tool holder.

The present disclosure relates to a quadrangular indexable drill insert. The drill insert includes a substantially flat top surface, a bottom surface and a side surface adjoining the top and bottom surfaces. The side surface comprises four identical cutting edges intersecting the top surface; each cutting edge comprises a first part edge oriented inwardly towards axis of the drill body. A second part edge tangential to an imaginary inscribed circle diameter connected to the first part edge through a convex curve. A third part connected to the second part edge through concave curve and a fourth part edge connected to the third part edge though a convex curve. The insert further includes a curved nose portion at four corners, each adjoining a first part edge of one cutting edge with a fourth part edge of a succeeding cutting edge.