A cutting tool for cutting a rotationally symmetrical surface of a rotating workpiece includes the step of feeding the cutting tool in a direction inclined with respect to a rotational axis of the rotationally symmetrical surface, while holding the cutting tool in contact with the rotationally symmetrical surface. In the step of feeding the cutting tool, the cutting tool has a point that is in contact with the rotationally symmetrical surface and the point shifts as the cutting tool is fed. The cutting tool includes: a rake face; a flank face; and a cutting edge connecting the rake face and the flank face. The cutting edge as seen from above the flank face has a shape including at least one arc, and the arc has a radius of curvature of not less than 100 mm and not more than 500 mm.

A cutting insert includes a rake face, a flank face, a cutting edge formed at a ridge where the rake face and the flank face intersect, a land provided on the rake face along the cutting edge, a breaker groove provided in the rake face inside of the land, and a curved surface formed between a groove surface of the breaker groove and the land. A radius of curvature of the curved surface is 0.5 mm or greater.

A tube deburring apparatus is disclosed and configured for deburring and beveling a terminal end of a tube. In at least one embodiment, the apparatus provides a deburring mechanism configured for use with a torque mechanism. The deburring mechanism provides a plurality of spaced apart bearings radially arranged about a center axis of rotation of a deburring body of the deburring mechanism and defining an imaginary receiving boundary sized for coaxially receiving the terminal end of the tube therewithin. The deburring body further provides a deburring bit positioned radially inwardly from the bearings, a deburring end of the deburring bit providing a cutting edge configured for selectively contacting the terminal end of the tube when the terminal end of the tube is coaxially positioned within the receiving boundary between the bearings.

In an embodiment, a cutting insert including a base member, a first face, a second face, a cutting edge, and a nose portion. The base member includes a coating layer on at least a part thereof. The first face has corner portions. The second face is adjacent to the first face. The cutting edge is on at least a part of the ridgeline portion of the first face and the second face, and includes first and second cutting edges. The first cutting edge is on the coating layer and has a C chamfered surface with a first width of 5 m to 30 m in the front view of the first face and a chamfer angle of 35 to 50. The nose portion is at the corner portions between the first cutting edge and the second cutting edge.

A method and a device for machining a workpiece rotating about a rotational axis. The machining point moves along the cutting edge of a cutting edge plane and the surface to be machined in a rolling movement on an advancement plane not intersected by the rotational axis. A pivot drive implements a large enough pivot angle so that a first workpiece surface is machined by a machining point moving along the first cutting edge in a first machining step. In a second machining step, a second workpiece surface is machined, wherein the machining point moves along the second cutting edge and the second workpiece surface. The cutting edge has a curvature radius smaller than the distance from the pivot axis of the holder to the cutting edge. The holder can additionally be displaced on the advancement plane with a movement component in a direction transverse to the rotational axis.

A cutting insert includes a land and a breaker flute on a rake face, the land providing a cutting edge by intersecting a flank face. The breaker flute includes breakers. A width T of a portion of the land that extends along a portion of the cutting edge that is at a round corner portion is 0.05 mm<T<0.15 mm. A plurality of crest portions each extending over the entirety of the portion of the cutting edge that is at the round corner portion are provided on a sloping surface of the breaker flute that is on a land side. The crest portions are arranged side by side in a depth direction of the breaker flute. A rake angle of at least one of inclined surfaces that form each of the crest portions is expressed as >20.

A cutting tool has a cutting insert removably secured to a holding portion of an insert holder. The cutting insert has opposing first and second end surfaces with an insert peripheral surface and a central axis extending therebetween, at least one cutting portion, and at least one mounting cut-out. Each cutting portion has a cutting edge and an adjacent relief surface facing in a first rotary direction about the central axis. Each mounting cut-out extends between the first and second end surfaces and has a first flank surface and an adjacent first upper slope surface. The first flank surface faces in a second rotary direction about the central axis and the first upper slope surface faces away from a median plane located midway between the first and second end surfaces. The first upper slope surface extends away from the median plane with increasing distance from the first flank surface.

A cutting tool has an insert holder and a cutting insert releasably attached thereto. The cutting insert has an insert edge which includes two nose cutting edges and a convex corner cutting edge which extends therebetween. The two nose cutting edges form a nose angle. The insert edge also includes two mid-side edges which are located further from the corner cutting edge than the nose cutting edges. The two mid-side edges form a mid-side angle. The nose angle is less than the mid-side angle.