An interlocking thread with a tooth-cross-section that is wider at its crest than at its root and with “V” angles located both along the crest and the root which tightens into a tapped hole that has a similar thread cross-section.

An interlocking thread with a tooth-cross-section that is wider at its crest than at its root and with “V” angles located both along the crest and the root which tightens into a tapped hole that has a similar thread cross-section.

A surface-coated cutting tool includes a substrate and a coating formed on a surface of the substrate, the coating including one or two or more layers, at least one of the layers being an Al-rich layer including hard particles, the hard particle having a sodium chloride type crystal structure, and including a first unit phase in a form of a plurality of lumps and a second unit phase interposed between the lumps of the first unit phase, the first unit phase being composed of a nitride or carbonitride of Al.sub.xTi.sub.1-x, the first unit phase having an atomic ratio x of Al of 0.7 or more and 0.96 or less, the second unit phase being composed of a nitride or carbonitride of Al.sub.yTi.sub.1-y, the second unit phase having an atomic ratio y of Al exceeding 0.5 and less than 0.7.

A surface-coated cutting tool includes a substrate and a coating formed on a surface of the substrate, the coating including one or two or more layers, at least one of the layers being an Al-rich layer including hard particles, the hard particle having a sodium chloride type crystal structure, and including a first unit phase in a form of a plurality of lumps and a second unit phase interposed between the lumps of the first unit phase, the first unit phase being composed of a nitride or carbonitride of Al.sub.xTi.sub.1-x, the first unit phase having an atomic ratio x of Al of 0.7 or more and 0.96 or less, the second unit phase being composed of a nitride or carbonitride of Al.sub.yTi.sub.1-y, the second unit phase having an atomic ratio y of Al exceeding 0.5 and less than 0.7.

A surface-coated cutting tool includes a substrate and a coating formed on a surface of the substrate, the coating including one or two or more layers, at least one of the layers being an Al-rich layer including hard particles, the hard particle having a sodium chloride type crystal structure, and including a first unit phase in a form of a plurality of lumps and a second unit phase interposed between the lumps of the first unit phase, the first unit phase being composed of a nitride or carbonitride of Al.sub.xTi.sub.1-x, the first unit phase having an atomic ratio x of Al of 0.7 or more and 0.96 or less, the second unit phase being composed of a nitride or carbonitride of Al.sub.yTi.sub.1-y, the second unit phase having an atomic ratio y of Al exceeding 0.5 and less than 0.7.

A tap 1 has a threaded portion 2 including a cutting blade 5 on an outer circumferential surface, a flute portion 3 that divides the threaded portion 2 in a circumferential direction, and a shank portion 4 formed continuously from the threaded portion 2 and the flute portion 3 along a central axis O. The flute portion 3 includes, in a cross-sectional view, a first flute 31 formed continuously from the cutting blade 5 of the threaded portion 2, a second flute 32 formed continuously from the first flute 31, and a ridge line portion 33 being a boundary between the first and second flutes 31, 32. A distance “e” from the central axis O to the ridge line portion 33 is longer than a distance d1 and a distance d2, respectively.

A tap 1 has a threaded portion 2 including a cutting blade 5 on an outer circumferential surface, a flute portion 3 that divides the threaded portion 2 in a circumferential direction, and a shank portion 4 formed continuously from the threaded portion 2 and the flute portion 3 along a central axis O. The flute portion 3 includes, in a cross-sectional view, a first flute 31 formed continuously from the cutting blade 5 of the threaded portion 2, a second flute 32 formed continuously from the first flute 31, and a ridge line portion 33 being a boundary between the first and second flutes 31, 32. A distance “e” from the central axis O to the ridge line portion 33 is longer than a distance d1 and a distance d2, respectively.

A tap and chaser are provided each having a cylindrical tool receiver connected to a threading section by a shaft. The receiver and shaft are of diameters sufficiently small to enter the bore hole and distribute any off axis load onto a number of internal threads of the bore hole to dissipate loading. The threaded section includes a group of longitudinal flutes. Each of the lands of the threaded section includes a novel cutting face, tooth angle and rake angle to advantageously allow for threading deep blind holes.

A tap and chaser are provided each having a cylindrical tool receiver connected to a threading section by a shaft. The receiver and shaft are of diameters sufficiently small to enter the bore hole and distribute any off axis load onto a number of internal threads of the bore hole to dissipate loading. The threaded section includes a group of longitudinal flutes. Each of the lands of the threaded section includes a novel cutting face, tooth angle and rake angle to advantageously allow for threading deep blind holes.

A thread forming tool comprises a thread generating region that extends along a helical line with a thread pitch angle and a thread direction of the thread to be formed and has an active profile corresponding to the thread profile of the thread to be formed, wherein the thread generating region has a thread tooth having a thread profile with a front thread tooth profile flank and a rear thread tooth profile flank, has a front flank relieved surface, adjoining the front thread tooth profile flank and has a rear flank relieved surface, adjoining the rear thread tooth profile flank, wherein the front flank relieved surface is isolated relative to a front thread tooth flank envelope, wherein the rear flank relieved surface is displaced relative to a rear transverse plane wherein the helical line is inclined to the rear relative to the rear transverse plane by the thread pitch angle.