Abstract: A tool for friction stir welding includes a tool part, a shank part and a cap part. The tool part and the shank part have a hexagonal frustum-shaped concave section and a hexagonal frustum-shaped convex section to enable movement of the tool part with respect to the shank part in a direction parallel to an axis of rotation while movement of the tool part with respect to the shank part in a direction around the axis of rotation is restricted, by the hexagonal frustum-shaped concave section and the hexagonal frustum-shaped convex section of the tool part and the shank part are fitted to each other. After the hexagonal frustum-shaped concave section and the hexagonal frustum-shaped convex section are fitted to each other, by the tool part and the shank part being covered by the cap part, the tool part is fixed to the shank part.

Abstract: A drill bit has a shank, an intermediate shaft, and a cutting head and defines a longitudinal axis. The cutting head has a body having a front end, a rear end, and a peripheral sidewall, a primary cutting insert and a pair of auxiliary cutting inserts. The primary cutting insert is cross-shaped with a central portion with a cutting tip and four cutting arms each with a cutting edge extending radially outward from the central portion past the peripheral sidewall. The auxiliary cutting inserts are spaced radially outward from the central portion and circumferentially from the radial cutting arms, and have a cutting edge extending radially outward past the peripheral sidewall. A pair of primary dust egress slots and a pair of auxiliary dust egress slots are formed in the peripheral sidewall and configured to channel debris from the front end to the rear end of the body.

Abstract: A drill head extending along a drill axis made of hard metal for rock drills is disclosed. The drill head features at least one major cutting edge and at least one minor cutting edge, where the major cutting edge extends from a first radially inner end to a first radial outer end which lies on a first diameter and where the minor cutting edge extends from a second radially inner end to a second radially outer end which lies on a second diameter that is smaller than the first diameter. A first enveloping surface defined by the minor cutting edge projects completely axially over a second enveloping surface defined by the major cutting edge.

Abstract: A drill bit for drilling a borehole in earthen formations comprising a bit body having a bit axis and a bit face. In addition, the drill bit comprises a primary blade extending radially along the bit face, the primary blade including a cutter-supporting surface that defines a blade profile in rotated profile view extending from the bit axis to an outer radius of the bit body. The blade profile is continuously contoured and includes a plurality of concave regions. Further, the drill bit comprises a plurality of cutter elements mounted to the cutter-supporting surface of the primary blade. Each cutter element on the primary blade has a forward-facing cutting face with a cutting edge adapted to penetrate and shear the earthen formation.

Abstract: A rolling cone drill bit includes a cutter element having a cutting portion with a chisel crest and a pilot portion extending beyond the chisel crest. The pilot portion includes a cutting surface that may be generally conical, or form a second chisel crest. The cutting tip of the pilot portion is supported by buttress portions which emerge from and extend beyond the flanks of the chisel crest to provide additional strength and support for the material of the pilot portion that extends beyond the height of the chisel crest.

Abstract: A drill bit comprises a plurality of cutting blades arranged circumferentially, the cutting blades having a cutting edge formed by a connecting ridge line between a cutting face and a flank; and a tip formed by coupling radially inner ends of the cutting edges to each other at a center portion of a bit tip end, wherein at least one of the cutting blades has a first flank and a second flank, wherein the first flank has a blade tip side flank close to the cutting edge and a base end side flank formed on the base end side of the blade tip side flank, and wherein a tilt angle ?1 of the blade tip side flank 3a is smaller than a tilt angle ?2 of the base end side flank 3b which is tilted toward the axial direction.

Abstract: A drill, which is used in a hammer drill for drilling holes in stone, concrete and the like, includes a one-piece drilling head (10, 20, 30) formed of a hard material and provided, at its first end (5), with at least one main bit having a tip (4) and at least one cutting structure (3) integral to the one-piece drilling head (10; 20; 30), and at a second end (6) located opposite the first end (5), with a bottom surface (7) for the mounting the drilling head (10; 20; 30) on the drill stem (8), and having a plurality of axially extending through-grooves (11; 21; 31) for removing drillings produced during a drilling process and having a cross-section which increases, at least regionwise, in a direction toward the bottom surface (7) of the drilling head (10; 20; 30).

Abstract: A cutting head for a drill bit has a body with an overall cruciform shape. One pair of opposing arms defines a main cutting edge. The other pair of opposing arms defines an auxiliary edge. The main cutting edge is defined by rake surfaces and relief surfaces. Each rake surface and relief surface is defined by a plurality of facets. The main cutting edge includes a chisel edge. A first pair of planar rake facets, one on each end of said chisel edge, and a first pair of planar relief facets, adjacent said chisel edge, defines a portion of the cutting edge. A remaining portion of the main cutting edge is defined at the apex of a plurality of curved rake facets and curved relief facets. The auxiliary edge is defined by a plurality of curved surfaces.

Abstract: A drill bit of the present invention is intended to stably perform drilling by lessening a great change in a drilling condition and to avoid reduction of a drilling efficiency even when large chip lumps are generated. In the drill bit, the main cutting blades have main cutting edges each structured such that an inner end thereof is located at the rotation center of the drill and an outer end thereof is located on an outer periphery of a rotation trace of the cutting blades, and the sub cutting blades have sub cutting edges each structured such that an inner end thereof is located to be spaced radially outward apart from the rotation center and an outer end thereof is located to be spaced radially inward apart from the outer periphery of the rotation trace toward the center of rotation.

Abstract: A drill bit for a hammer drill for drilling in stone, concrete and the like includes a drill bit head formed as a hard material body with radial legs and having at least three radially extending cutting bits formed on the radial legs, and a centering tip in a center of the hard material body and projecting beyond one of the cutting bits, with the centering tip having concave limiting surfaces stretching between the linearly extending auxiliary cutting edges.

Abstract: A rotary hammerdrill bit for use with a percussion drilling device or a hammer drilling device, with a shank and a drill head attached to or configured on the shank, wherein a front side pointing in the advance direction of the drill head has a main cutting plate forming a main cutting axis. The main cutting plate extends over the diameter of the drill head and has a tip or tip-edge lying in the longitudinal axis of the drill bit and forms drill blades that are substantially roof-shaped and are inclined radially from the tip or tip-edge. The front side of the drill head has at least one pair of cutting pins, wherein the cutting pins are arranged on the drill head in essentially the same radial positions.

Abstract: An auxiliary cutting plate (10) for a multi-cutting plate drill bit (2) has a body (44) for fixing into a slot in the drill bit (2) and a profiled tip (46). The body (44) has a central longitudinal axis and the profiled tip (46) protrudes from one end of the body (44). The profiled tip (46) has a cutting edge (62) defined by a transition between a rake face (64) and a relief face (66). The rake face (64) and the relief face (66) each slope axially rearward from opposite sides of the cutting edge (62). The angle of inclination ? of at least a portion of the rake face (64), measured from a plane perpendicular to the longitudinal axis, decreases with increasing distance from the cutting edge (62).

Abstract: The invention provides a T-post hole-forming device, comprising (a) a shaft; (b) a head for receiving a driving force at the top of said shaft; (c) a flat plate affixed to one side of said shaft, the shaft terminating in a pointed end for piercing the ground. Also provided is a method for installing a T-post into the ground. The method involves (a) piercing the ground with the T-post hole-forming device to produce a hole; (b) removing the device from the ground, and (c) inserting a T-post into the hole, thereby installing the T-post into the ground.

Abstract: The invention relates to a drilling tool (1), in particular for working concrete, rock, masonry and suchlike materials, having a tool head with cutting body (5) which has at least one front rake face (9, 10), at least one rear flank ([lacuna] 18) and at least one front-end cutting edge (7, 8), the cutting edge (7, 8) separating the rake face (9, 10) and the flank ([lacuna] 18). In this case, the rake face (9, 10) is formed by at least two cutting faces (11, 13; 12 [lacuna]) merging into one another at at least one second cutting edge (15, 16).

Abstract: A drill bit that has a drill bit body with a side wall and opposite ends. A distal one of the opposite ends of the drill bit body receives a cutting insert. The drill bit body contains at least two helical debris ports in the side wall thereof. The drill bit body further contains a helical scallop that corresponds to each one of the helical debris ports. Each one of the helical scallops surrounds so as to define the periphery of its corresponding one of the helical debris ports.

Abstract: A down hole rock drill bit and method of manufacture of the same comprising a cast metal drill bit body having a plurality of hardened carbide studs partially cast in the drill bit body. The drill bit is cast by means of a foam pattern replicating the drill bit, typically made from polystyrene within which a plurality of carbide studs are partially inserted into the grinding surface of the foam drill bit model. The model is then subsequently supported within a vessel of sand and molten metal is poured over the foam, vaporizing it and taking the exact form of the foam pattern and permanently retaining the carbide studs within the metal drill bit.

Abstract: A flightless rock auger is used for drilling postholes through rock with the use of hydraulic pressure and at slow revolution per minute. The rock auger is used in combination with a conventional flighted auger used for drilling postholes in dirt and clay. During a posthole drilling operation, the rock auger is substituted for a conventional flighted auger as needed for drilling through and removing rock or other hard material such as concrete from the posthole. The rock auger is designed for use at very low revolutions per minute and can function utilizing only the weight of the auger; however, the rock auger is designed for use with pressure drilling units as well for cutting a circular hole through the rock and forming a plug which is to be lodged in the cavity of the rock auger cylinder to be removed from the posthole.

Abstract: A rock drill head including a radially extending groove (2a) formed in a head body, a recess (5) formed inside the groove (2a); and at least two, substantially plate-shaped, hard-material inserts located in the groove (2a) and having each a radially extending, segment (4a, 4b) engaging in the recess (5).

Abstract: A drill head for rock drilling comprising cutting edges (1) made of hard material, which is detachably connected axially, over a bearing surface (3), with a drilling shaft (4) with at least one radially projecting driver blade (5a, 5b, 5c) by a bayonet-type connection slot (6a, 6b, 6c), wherein at least one connection slot (6a, 6b, 6c) is present, which forms two axially opposing undercuts (7a, 7b), within which the driver blade (5a, 5b, 5c) has limited axial movement.

Abstract: A rotary drill bit for boring a hole through a solid body is disclosed. The drill bit comprises a collar and a penetrating member. At a proximal end, the collar is attachable to a drill shaft. At a distal end, the collar is attachable to the penetrating member. The penetrating member has a connecting end for attachment to the collar and a cutting end for engaging the solid body. A pilot drill is fixedly attached to the cutting end for initiating contact with the solid body.

Abstract: A rock drill including a drill stem (2), major cutting edges (5, 6) extending substantially over a diameter of the drill stem (2) and projecting beyond the end face (3) of the drill stem, and at least one minor cutting edge (9, 10) extending substantially in a radial direction and provided on at least one elongate cutting body (7, 8) which projects beyond the end face (3), with the minor cutting edge (9, 10) being located, at a contemplated rotational direction (R) of the drill (1) about the drill axis (A), in front of a corresponding major cutting edge (5, 6) adjacent to a main discharge groove (13) for drilling dust, and with the elongate cutting body (7, 8) having a cutting surface (11) tapering from the minor cutting edge (9) toward the end face (3) of the drill stem (2) and having at least one inclination surface (12) adjacent to the circumference of the drill stem (2) and inclined toward the circumference of the drill stem and with respect to a radial extension of the minor cutting edge (9), in a direct

Abstract: A solid hard metal head for a drill, including two main cutting edges (2) arranged substantially diametrially opposite each other, and two auxiliary cutting edges (3) likewise arranged substantially diametrically opposite each other, with associated main cutting edge (2) and auxiliary cutting edge (3) form an acute angle (&agr;) there between, and with the auxiliary cutting edges (3) being arranged, with respect to the rotational direction (&ohgr;) of the drill, in front of the respective, associated therewith, main cutting edge (2).

Abstract: A rotary drill bit for boring a hole through a solid body is disclosed. The drill bit comprises a collar and a penetrating member. At a proximal end, the collar is attachable to a drill shaft. At a distal end, the collar is attachable to the penetrating member. The penetrating member has a connecting end for attachment to the collar and a cutting end for engaging the solid body. A pilot drill is fixedly attached to the cutting end for initiating contact with the solid body.

Abstract: A percussive blow assisted rotary drill, has an axially extending shank (1) with a leading end face (3) and an axially extending outside surface (2) with helically extending drilled material removal grooves in the outside surface. A hard metal main cutting plate (6) and hard metal auxiliary cutting plates (11) are seated in an axially extending leading end region of the shank and are arranged in an X-shaped pattern. The main cutting plate and auxiliary cutting plates project axially outwardly from the leading end face (3) and radially outwardly from the outside surface (2). The auxiliary cutting plates project axially and/or radially outwardly beyond the main cutting plate and, relative to the rotational direction (R) of the drill, the auxiliary cutting plates and the main cutting plate lagging the auxiliary cutting plates form an acute angle. The main drilled material removal grooves are located upstream, relative to the rotational direction, of the auxiliary cutting plates.

Abstract: A tool component comprises an abrasive compact layer bonded to a cemented carbide substrate along an interface. The abrasive compact layer has a working surface on a side opposite to the interface which is flat and which presents a cutting edge or point on its periphery. A recess is provided, that recess extending into the substrate from the interface. The recess has a shape, in plan, of at least two strips which intersect. Examples of suitable shapes are V-shape and cross-shape. Abrasive compact fills the recess and is bonded to the substrate.

Abstract: A rock drill haivng a drill head with cruciform cutting tips is proposed which has improved chiselling properties in the case of percussive loading in hard rock or the like. For this purpose, the main cutting tip (4) is of a design know per se with secondary cutting tips (7,8) which are arranged transverse thereto and have a roof-shaped cross-section in side elevation. Additional, radially further outward bit points (16) for working the material result from the roof-shaped cross-section of the secondary cutting timps (7,8,) (cf. drawing).

Abstract: Methods and apparatus are provided for extending the effective length of a jet of fluid exiting a nozzle. An elongated jet extension member extends substantially axially outward from a nozzle outlet, and the jet of fluid flowing along and around the extension member tends to cling to the extension member thus decreasing the angle of divergence of the fluid jet.