A method for producing a replaceable cutting head is described. The replaceable cutting head is manufactured by extruding a blank. During extrusion of the blank, a number of helical coolant channels and a number of helical flutes are simultaneously formed. After extrusion, the flutes have a first angle of twist (D1), and the coolant channels have a second angle of twist (D2). After extrusion, the blank is sintered and then reworked to selectively adjust the first angle of twist (D1) and the pitch of the flutes. The method produces an endless blank that is capable of being parted off to a desired length without any sacrificial allowance, which provides significant material and cost savings as compared to conventional methods.

A method for producing a replaceable cutting head is described. The replaceable cutting head is manufactured by extruding a blank. During extrusion of the blank, a number of helical coolant channels and a number of helical flutes are simultaneously formed. After extrusion, the flutes have a first angle of twist (D1), and the coolant channels have a second angle of twist (D2). After extrusion, the blank is sintered and then reworked to selectively adjust the first angle of twist (D1) and the pitch of the flutes. The method produces an endless blank that is capable of being parted off to a desired length without any sacrificial allowance, which provides significant material and cost savings as compared to conventional methods.

A drill has a first main body portion and a second main body portion. The first main body includes a chip discharging surface, a flank face, and an outer peripheral surface. A ridgeline between the chip discharging surface and the flank face constitutes a cutting edge. The chip discharging surface has an auxiliary flute surface provided in a form of a helix around a center axis, the auxiliary flute surface being contiguous to the cutting edge, the auxiliary flute surface being recessed in a direction opposite to a rotation direction of the drill. An auxiliary cutting edge portion has a first end portion and a second end portion. When viewed in a direction along the center axis, a value obtained by dividing the maximum value of the diameter of the second main body portion by the diameter of the first main body portion is 1.5 or more.

There is provided a drill insert for drilling metallic or other materials, comprising a drill insert body with first and second lands at the outside diameter of the body that interface with the wall of a drilled hole. There is provided a coolant relief arrangement at the outside diameter of the drill insert by a plurality of coolant supply channels extending between the leading edge and trailing edge of the interface, to provide coolant relief to the outside diameter of the drill insert at the interface with the drilled hole. The drill inserts of the invention provide reduced friction and heat generation while maintaining high stability, and operate to prevent accumulation of materials on surfaces of the drill inserts at the outside diameter of the drill insert. This enables higher penetration rates and operating speeds while maintaining integrity of the drill inserts.

There is provided a drill insert for drilling metallic or other materials, comprising a drill insert body with first and second lands at the outside diameter of the body that interface with the wall of a drilled hole. There is provided a coolant relief arrangement at the outside diameter of the drill insert by a plurality of coolant supply channels extending between the leading edge and trailing edge of the interface, to provide coolant relief to the outside diameter of the drill insert at the interface with the drilled hole. The drill inserts of the invention provide reduced friction and heat generation while maintaining high stability, and operate to prevent accumulation of materials on surfaces of the drill inserts at the outside diameter of the drill insert. This enables higher penetration rates and operating speeds while maintaining integrity of the drill inserts.

There is provided a drill tool assembly for drilling metallic or other materials, comprising a holder having a mounting slot in which a cutting insert is positioned, and a through tool coolant supply system. The drilling tool system allows for the application of coolant to the rake surfaces of the cutting insert in a manner which facilitates enabling higher penetration rates while maintaining integrity of the cutting edges of the cutting insert. The drilling tool system comprises a holder having a rotational axis and mounting slot. A cutting insert with sides positioned adjacent the side surfaces of the mounting slot and cutting edges extending from the rotational axis is mounted in the slot. The insert includes rake surfaces adjacent the cutting edges that are positioned above the mounting slot. At least one coolant channel is disposed with at least one coolant outlet directed at the sides of the insert at a position below the rake surfaces. The coolant outlet is configured to disperse coolant in a curtain across the entire rake face of each cutting edge.

There is provided a drill tool assembly for drilling metallic or other materials, comprising a holder having a mounting slot in which a cutting insert is positioned, and a through tool coolant supply system. The drilling tool system allows for the application of coolant to the rake surfaces of the cutting insert in a manner which facilitates enabling higher penetration rates while maintaining integrity of the cutting edges of the cutting insert. The drilling tool system comprises a holder having a rotational axis and mounting slot. A cutting insert with sides positioned adjacent the side surfaces of the mounting slot and cutting edges extending from the rotational axis is mounted in the slot. The insert includes rake surfaces adjacent the cutting edges that are positioned above the mounting slot. At least one coolant channel is disposed with at least one coolant outlet directed at the sides of the insert at a position below the rake surfaces. The coolant outlet is configured to disperse coolant in a curtain across the entire rake face of each cutting edge.

A coolant supply mechanism is attachable to a cutting insert. The cutting insert has a first bottom surface, a first upper surface, and a first side surface. The first upper surface includes a corner portion that is located at a corner of the first upper surface when viewed in a plan view and that is contiguous to the first side surface so as to form a cutting edge, and a center portion located adjacent to the corner portion on a side opposite to the cutting edge when viewed in a plan view. The first upper surface is depressed toward the first bottom surface side at the center portion.

A drilling tool includes a tool body having a center axis defining a longitudinal direction of the drilling tool. The tool body has an axially forward end and an axially rearward end, the distance in the longitudinal direction between the forward end and the rearward end defining a length of the drilling tool. At least two indexable cutting inserts are arranged at the axially forward end, a first indexable cutting insert being arranged at a radially inner position and a second indexable cutting insert being arranged at a radially outer position. The tool body includes a first flute portion extending axially rearward from the first indexable cutting insert and a second flute portion extending axially rearward from the second indexable cutting insert. The first flute portion transitions into the second flute portion at an axially forward transition area of the tool body, thereby forming only one flute of the tool.

A drilling tool includes a tool body having a center axis defining a longitudinal direction of the drilling tool. The tool body has an axially forward end and an axially rearward end, the distance in the longitudinal direction between the forward end and the rearward end defining a length of the drilling tool. At least two indexable cutting inserts are arranged at the axially forward end, a first indexable cutting insert being arranged at a radially inner position and a second indexable cutting insert being arranged at a radially outer position. The tool body includes a first flute portion extending axially rearward from the first indexable cutting insert and a second flute portion extending axially rearward from the second indexable cutting insert. The first flute portion transitions into the second flute portion at an axially forward transition area of the tool body, thereby forming only one flute of the tool.