Osg Corporation | Date: 2012-03-09
A spiral tap including: a screw portion provided with a male screw; a primary flute in a helical shape formed to intersect with a screw thread of the male screw; and a secondary flute formed in a tip portion in the primary flute at a helix angle smaller than a helix angle of the primary flute, the secondary flute having a positive or negative helix angle of 0 to 3 degrees, the spiral tap further including a cutting edge being formed on a ridgeline between a side wall surface toward a tap rotation direction out of a pair of side wall surfaces of the secondary flute and an outer circumferential surface of the screw portion and having a rake angle of 10 to 0 degrees, and the secondary flute having a flute bottom slope of 5 to 15 degrees.
Osg Corporation | Date: 2012-04-09
A hard coating for a cutting tool being highly resistant to both wear and seizure; and a cutting tool coated with the hard coating. This hard coating is a multilayer film including two or more of the following layered in alternation: first coating layers including Ag
Osg Corporation | Date: 2012-04-02
A cutting tool hard film disposed as coating on a surface of a cutting tool, includes: a hard phase that is a nitride phase, an oxide phase, a carbide phase, a carbonitride phase, or a boride phase containing at least one element out of group IVa elements, group Va elements, group VIa elements, Al, and Si; and a binding phase that is a phase containing at least one element out of Au, Ag, and Cu, the cutting tool hard film having composite structure with the hard phase and the binding phase three-dimensionally arranged.
Osg Corporation | Date: 2013-03-26
A three-flute drill having: a tool main body with cutting edges at an axially distal end thereof, a flute portion having discharge flutes in a distal-end side portion of the body, and a cutting fluid supply hole for supplying fluid toward the edges, a rear inner wall surface on the radial direction on a rear side in the drill rotation direction and opposed to the front inner wall surface in a drill circumferential direction, an outer circumferential inner wall surface made up of a partially cylindrical surface whose center lies on an axis of the drill, and an inner circumferential inner wall surface having a partially cylindrical surface whose center lies on the drill axis and opposed to the outer circumferential inner wall surface in the radial direction, the inner circumferential inner wall having a curvature radius smaller than that of the outer circumferential inner wall surface.
Osg Corporation | Date: 2012-07-17
A spiral tap has a male thread disposed on an outer circumferential portion and a cutting edge formed along a spiral flute disposed spirally around an axial direction so as to divide the male thread, the spiral tap is disposed with a sub-groove formed into a concave shape along a back edge of the spiral flute to make a rake angle of the back edge positive at least in a portion corresponding to a biting portion of the spiral tap in the spiral flute, and a curvature radius of the sub-groove is smaller than a curvature radius of the spiral flute in a cross section perpendicular to the axial direction.