A turning method for a computerized numerical control lathe performs the steps of: providing a cutting tool including a coupling portion, an intermediate portion and a cutting portion, a longitudinal center axis of the coupling portion defining a tool rotational axis, the cutting portion including a top surface, a first nose portion, the first nose portion including a first cutting edge, a second cutting edge, and a convex nose cutting edge connecting the first and second cutting edges; providing and rotating a metal work piece around a work piece rotational axis, which is set perpendicular to the work piece rotational axis; making a first pass where the first cutting edge is active and the second cutting edge is inactive; making a second pass where the first cutting edge is inactive and the second cutting edge is active; and rotating the turning tool around the tool rotational axis.

A cutting insert has a seating surface, an outer peripheral surface, a top surface, and an attachment hole. The cutting edge includes a curved cutting corner edge portion, a first cutting edge portion, and a second cutting edge portion. The top surface includes a first rake face contiguous to the first cutting edge portion, a second rake face contiguous to the second cutting edge portion, and a third rake face contiguous to the cutting corner edge portion and also contiguous to the first and second rake faces. The third rake face has a first region contiguous to the first rake face and a second region contiguous to the second rake face. The first rake face and the first region each have a rake angle which is a positive angle. The second rake face and the second region each have a rake angle which is a negative angle.

Drilling tool systems including a drilling body and a drilling inserts are disclosed. The drilling inserts include four indexable cutting edges. The four cutting edges may each comprise a plurality of cutting edge segments and a wiper edge. The plurality of cutting edge segments and the wiper edge are provided at distinct angles to provide effective chip breaking and a stronger cutting edge at the drilling insert corners. Furthermore, the side surfaces of the drilling inserts allow the drilling insert to be more stably supported in a pocket of the drilling body. The drilling inserts may be used in a peripheral pocket of a drilling body.

Drilling tool systems including a drilling body and a drilling inserts are disclosed. The drilling inserts include four indexable cutting edges. The four cutting edges may each comprise a plurality of cutting edge segments. The plurality of cutting edge segments are provided at distinct angles with respect to a reference plane of the drilling insert to provide effective chip breaking and a stronger cutting edge at the drilling insert corners. Furthermore, the side surfaces of the drilling inserts allow the drilling insert to be more stably supported in a pocket of the drilling body. The drilling inserts may be used in a central pocket of a drilling body.

A cutting insert may include a first surface, a second surface and a third surface. The first surface may include a corner having a convex curvilinear shape and an inclined surface. The inclined surface may include a first inclined surface, a second inclined surface and a third inclined surface. The first inclined surface may be inclined at a first angle. The second inclined surface may be inclined at a second angle. The third inclined surface may be inclined at a third angle. The first inclined surface may have a concave curvilinear shape in a cross section orthogonal to a bisector of the corner. The second inclined surface may be a flat surface. The second angle may be smaller than either of the first angle and the third angle in a cross section which includes the bisector and is orthogonal to the reference plane.

A tool system for machining includes a tool body that has a first end for connecting to a machine tool and a second end having an end face on which a seat for an interchangeable cutting insert is formed. The cutting insert has an underside formed as an abutment surface, a top side formed as a rake face, and an encircling side face formed as a flank, and a cutting edge is formed at a transition from the top side to the encircling side face. The cutting insert is arranged on the seat such that the top side extends perpendicularly to the longitudinal axis of the tool body and the cutting edge protrudes beyond the outer circumference of the end face of the tool body in a radial direction with respect to the longitudinal axis with two usable cutting corners and cutting-corner portions adjoining the latter on both sides.

A cutting tool includes a cutting insert resiliently clamped in an insert holder. The insert holder has a holder longitudinal axis defining opposite forward to rearward directions, and a transversely oriented insert receiving pocket having a pocket longitudinal axis and a pocket front opening. The insert holder includes a forwardly located insert mounting portion that includes upper and lower jaws which together define the insert receiving pocket. The insert receiving pocket at the lower jaw includes a pocket lower clamping surface. The insert receiving pocket at the upper jaw includes a pocket upper clamping surface which faces mutually towards the pocket lower clamping surface. The insert receiving pocket at one of the upper and lower jaws includes a pocket stopper surface facing generally towards the pocket front opening. The upper jaw includes an outer flexibility groove recessed in the holder peripheral surface.

A polygonal cutting blade having a circular arc-shaped groove in a hole includes a blade body composed of an upper surface, a lower surface and a plurality of main side surfaces connecting the upper surface and the lower surface. The blade body has a central hole penetrating through the upper surface and the lower surface, and is centrally symmetrical about a central axis of the central hole. At least one set of positioning side surface comprised of adjacent two of the main side surfaces is provided. An inner surface of the central hole has at least one circular arc-shaped groove fitting with a fastening screw for fixing the cutting blade. The circular arc-shaped groove directly faces toward an intersection of the two main side surfaces of the set of positioning side surface. A groove central axis of the circular arc-shaped groove has an offset distance from the central axis.

A cutting head attachment assembly for a cutting tool includes a body forming an axially forward part of the cutting tool attachable to a cutting head via a clamping element and a fixation element. A guide surface provided at the body or cutting head extends in both a radial and an axial direction to support movement of the clamping element in both the radial and axial directions via actuation of the fixation element to force and clamp together axially the head and body.

Whirling tool for machining a workpiece. The whirling tool comprises a plurality of cutting inserts, a cutting insert carrier, and a coolant channel which is arranged in the cutting insert carrier. The cutting insert carrier comprises a plurality of cutting insert receptacles for receiving and releasably fastening respectively one of the cutting inserts. The cutting insert receptacles are arranged so as to be distributed in the circumferential direction over the cutting insert carrier. The cutting insert carrier further comprises a through-opening which extends along a central axis of the cutting insert carrier, and through which the workpiece can be passed during the machining. The cutting inserts protrude into the through-opening, and the coolant channel extends between an inlet opening and an outlet opening, wherein the outlet opening leads into the through-opening and/or is oriented towards the through-opening.