Boring tool with coolant hole

摘要

The object of the present invention is to prevent chips created when cutting the inner diameter of a hole in a workpiece from entering the narrow space between the workpiece and the belly of the shank and to reduce damage to the cut surface by these chips. In a boring tool with a coolant hole, a spray opening (3) of a coolant hole (2) formed in a shank (1) is positioned with a radial offset from the shank center toward the side on which a cutting tool (4) is formed. As seen from a plane view of the boring tool, the spray opening (3) is sloped at an angle of 0 to 10 deg from an axial center C of the shank toward a cutting edge (4a). Also, the spray opening (3) is positioned so that a distance L from the cutting edge (4a) is up to three times the shank diameter.