A cutting tool including an insert and a holder to which the insert is secured. The insert has a rod with a substantially circular transverse cross-section. The insert includes a shank portion and a cutting edge portion. The cutting edge portion is located at an end portion continuous with the shank portion. In the cutting edge portion, one end of a cutting edge ridge protrudes toward the periphery of the rod. When the insert is secured to the holder, the cutting edge ridge has a negative radial rake angle.

A turning tool for internal turning of a metal work piece having a rear end, an opposite forward end and a longitudinal center axis extending therebetween. The first nose cutting edge includes a first radially distal point having an associated first rake face and separates and connects a first forward cutting edge and a first rearward cutting edge. A second nose cutting edge of the turning tool includes a second radially distal point having an associated second rake face and separates and connects a second forward cutting edge and a second rearward cutting edge. The second radially distal point is positioned ahead of the first radially distal point. The first forward cutting edge forms an acute first entering angle, the second forward cutting edge forms an obtuse second back clearance angle, and the second rearward cutting edge forms an acute second entering angle.

A fixing device for fixing a boring bar on a material-removing machine includes a reducing sleeve with a hollow profile arranged on a front face which faces away from a machine chuck. The boring bar is received in the interior of the hollow profile. An end region of the boring bar projects from the hollow profile and carries a cutting tool. The hollow profile has a wall arranged between a hallow profile interior and a hollow profile outer wall. The wall has a lateral region where the cutting tool projects from the boring bar, a first thickness in the lateral region, and a second thickness outside the lateral region. The first thickness is less than the second thickness. A longitudinal axis of the hollow profile is parallel to and at a distance from the axis of the reducing sleeve which is coaxial with the interior of the boring bar.

A cutting tool may include a main body having a bar shape extended along a central axis. The main body may include a cutting edge, a first flow path, a second flow path, a third flow and a fourth flow path. The first flow path is located along the central axis and may include an inflow port. The second flow path is located along the central axis and may include a smaller inner diameter than the first flow path. The third flow path may connect to the first flow path and may include a first outflow port. The fourth flow path may connect to the second flow path and may include a second outflow port. The first outflow port is located more away from an imaginary plane including the central axis and the cutting edge than the second outflow port.

A boring-bar arrangement includes a boring bar, a securing device, and a clamping bolt. The securing device has a reduction sleeve, which is secured in a tool chuck, which has a front end that faces away from the tool chuck and a protruding hollow section which receives the boring bar. The hollow section has a hollow-section interior, a hollow-section outer wall, and a hollow-section wall which is arranged therebetween. The hollow-section wall has a first thickness in a side region where the cutting tool protrudes from the boring bar which is less than a second thickness in a rest of the hollow-section wall. The boring bar is releasably secured as a replaceable head, via its back end, at a front end of the protruding hollow section. A front end of the clamping bolt has a male thread which sits in the female thread of the boring bar.

A coated tool may include a base member and a coating layer located on the base member. The coating layer may include a plurality of AlTi layers including aluminum and titanium as a main component, and a plurality of AlCr layers including aluminum and chromium as a main component. The AlTi layers and the AlCr layers may be located alternately one upon another. The plurality of AlTi layers may include a first AlTi layer and a second AlTi layer located farther away from the base member than the first AlTi layer. Each of the plurality of AlTi layers may further include chromium, and a content ratio of chromium in the second AlTi layer may be higher than a content ratio of chromium in the first AlTi layer.

An indexable cutting insert has a central mounting portion and two cutting portions. The central mounting portion has opposing upper and lower surfaces. The lower surface has two abutment elements associated therewith, each abutment element having two diverging abutment surfaces forming two abutment angles. The two cutting portions extend away from the central mounting portion, have distal cutting edges, and are entirely located in diagonally opposite imaginary quadrants of four quadrants defined by two mutually perpendicular quadrant planes. Two abutment bisector planes bisecting the two abutment angles and one of the quadrant planes are parallel or coincident. In a top view, the two cutting portions extend away from the central mounting portion in opposite directions. Two cutting bisector lines parallel to the two directions and bisecting the two cutting edges are mutually offset. A cutting tool has an insert holder and the cutting insert removably retained therein.

A cemented carbide may include a hard phase that may include W and C, a first solid solution phase and a second solid solution phase, each of which may include W, C, Ti and Zr, and a binder phase that may include an iron group metal. The cemented carbide may include 1.0-3.0 mass % of the Ti in terms of TiC, and 0.75-2.0 mass % of the Zr in terms of ZrC. An amount of the Ti in terms of TiC may be more than 1 time and less than three times an amount of the Zr in terms of ZrC. The first solid solution phase may satisfy a relationship of 0.1≤Ti/(Ti+Zr)<0.4 in terms of atomic ratio. The second solid solution phase satisfies a relationship of 0.7≤Ti/(Ti+Zr)≤0.9 in terms of atomic ratio.

A cutting tool includes a cutting member having a shank portion located in a clamping recess of a clamping sleeve adaptor of a holding device. The shank portion has a peripheral shank surface including a switching arrangement including two circumferentially spaced apart circumferential outer portions and a circumferential inner portion extending therebetween. The circumferential inner portion has opposite electrical conductivity to the two circumferential outer portions. The holding device has an alignment indicating unit including an electric switch including two spaced apart conductive switch members configured to be in electrically conductive communication or non-communication with each other thereby closing or opening the electric switch, so that an electric circuit established or broken, forming first and second states of the cutting tool, respectively. Switching between the first and second states is realized by rotation of the cutting member with respect to the clamping sleeve adaptor.

Provided is a cutting insert having two cutting parts that is capable of entering a workpiece more deeply and easily supports machining of a groove or hole having a small diameter in a workpiece. A cutting insert includes: a body having at least an inner surface to be fixed to a tool body of a cutting tool and an outer surface opposed to the inner surface; and two cutting parts protruding in opposite directions in a longitudinal direction of the body. The cutting part includes: a cutting upper surface; a cutting front surface; and a first cutting side surface and a second cutting side surface. A front cutting edge is located on an edge between the cutting upper surface and the cutting front surface. In a projection view of the body as seen from the longitudinal direction, the cutting upper surfaces of the two cutting parts are oriented in directions opposed to each other, and front cutting edges of the two cutting parts are disposed so as to be more away from each other as being closer to the first cutting side surface from the second cutting side surface.