A cutting insert rotatable about an axis, has opposing front and rear surfaces interconnected by an insert peripheral surface, the insert peripheral surface having first and second side surfaces spaced apart by first and second land surfaces. First and second land edges extend along the first and second land surfaces, respectively. A first front edge formed at the intersection of the front surface and the first side surface includes a cutting-edge portion, and a second front edge formed at the intersection of the front surface and the second side surface is devoid of a cutting-edge portion. A cutting profile formed by rotating the cutting-edge portion about the axis is located axially forward of the second front edge. The cutting insert is releasably secured to a tool shank, the cutting insert being located between two protuberances protruding from a forward end portion of the tool shank.

The invention relates to a single-lip drill with an inner and an outer rake face. Very good hole straightness deviation values and endurance are obtained with the ground face according to the invention.

A drilling tool is provided, which is configured to prevent an insufficient chip discharge ability thereof. The drilling tool includes a cutting insert having a cutting edge at a leading end portion, and a body to which the cutting insert is mounted. The drilling tool also includes a recessed part provided on an outer peripheral surface of the body and extending to a leading end of the body, and an oil supply port provided on a base end side of the recessed part and supplying cutting oil, passing through the inside of the body, to an outer peripheral side of the body. In a case where the drilling tool further includes a guide pad that comes into abutment with an inner wall surface of a hole cut by the cutting insert, and a fastening screw for fixing the guide pad to the body, the oil supply port may be provided at a position further toward the base end side of the body than a position of the fastening screw.

A method for reloading a single-flute drill comprising a shaft made of a hard metal and a drill head that is connected to the shaft and is made of a hard metal, is characterized by the following steps: removing a worn drill head from the shaft; integrally bonding a new drill head to the shaft.

A drilling tool is provided, which is configured to prevent an insufficient chip discharge ability thereof. The drilling tool includes a cutting insert having a cutting edge at a leading end portion, and a body to which the cutting insert is mounted. The drilling tool also includes a recessed part provided on an outer peripheral surface of the body and extending to a leading end of the body, and an oil supply port provided on a base end side of the recessed part and supplying cutting oil, passing through the inside of the body, to an outer peripheral side of the body. In a case where the drilling tool further includes a guide pad that comes into abutment with an inner wall surface of a hole cut by the cutting insert, and a fastening screw for fixing the guide pad to the body, the oil supply port may be provided at a position further toward the base end side of the body than a position of the fastening screw.

A quick-changing brazed drill includes a drill body and a quick-changing joint. The drill body is connected to the quick-changing joint detachably, and a vent hole is provided at a connection point between the drill body and the quick-changing joint. The drill body has a cylindrical structure, an interior of a front end of the drill body is hollow, and an outer side of the front end of the drill body is provided with 2-6 grooves. The quick-changing joint includes a transition block and a rear cover; a rear end of the transition block is connected to the rear cover by an external thread; a snap-fit area is provided between the transition block and the rear cover; a middle portion of the transition block is provided with a first threaded hole and is connected to a rear end of the drill body.

Provided are a guide pad having sufficient strength and a gun drill having the guide pad. A guide pad includes: a first surface; a second surface that is a flat surface located at a position opposed to the first surface; and a third surface that connects the first surface and the second surface to each other. When viewed along a rotational center axis, the first surface is a circular-arc-shaped surface, and when a point at which a virtual line passing through a circular-arc center of the first surface and perpendicular to the second surface and the second surface cross each other is assumed as a first point and a point at which a central axis of the through hole and the second surface cross each other is assumed as a second point, the first point is located at a position closer to the third surface than the second point.

Provided is a body capable of suppressing the bending of the body during machining. A body includes: a first mounting part serving as a portion that is provided on a leading end side and has a cutting edge mounted thereon; and a second attachment part serving as a portion that is provided at a position different from a position of the first mounting part along a circumferential direction and has a guide pad attached thereto on the leading end side. One discharging groove that extends from the leading end side to a base end side and is used to guide and discharge a fluid to the base end side is formed on an outer peripheral surface of the body, and at least a part of the discharging groove is bent.

The invention relates to single-lip drills in which two longitudinal grooves are formed in the rake face. They are arranged in the longitudinal direction of the tool, spaced apart from one another by a ridge and favor chip breaking.

A single-edge drill for forming a deep hole is provided which includes a body and a shank. The body has a single chip discharge groove in the outer periphery thereof, and includes a small-diameter portion, and a large-diameter portion having coolant delivery grooves in the outer periphery thereof. The body has a core thickness at the distal end portion of the large-diameter portion. At the other portion of the body, the groove bottom of the chip discharge groove is located beyond the rotation center of the drill such that the body has no core thickness, and when taken perpendicularly to the axial direction of the drill, the cross section of the body has a crescent shape. When a hole is formed with the drill, a supply path for coolant liquid is defined between the outer peripheral surface of the small-diameter portion and the radially inner surface of the hole.