Abstract: There is now provided a twist drill having an elongate body at a first end, a shank at a second and opposite end, the elongate body and the shank sharing a common axis, at least one face on the elongate body at an end opposite the shank, wherein the at least one face defines a corresponding flute extending along the elongate body toward the shank, at least one flank on an end of the elongate body at an end opposite the shank, and a cutting edge at a juncture of the at least one face and the at least one flank, and the like tools, having a sintered cemented carbide body, and the use thereof in material removing and dislodging tools.

Abstract: A cutting insert for a cutting or breaking tool, which can be mounted in a tool holder that can be rotated about its longitudinal axis, especially for a lathe chisel, has an essentially conical tip, a transition region and a foot for connecting to a tool body, wherein the transition region has several spatial areas which are distributed over its periphery and adjoin one another forming spatial and cutting edges.

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 drill including a body having mortises (7), and a solid hard metal head (4) having a plurality of bits (3) and secured to the drill body over the end surface (5) of the head (4) and additionally secured to the drill body over portions of side surfaces (6) located in a radially outer region of the head (4), extending substantially parallel to a rotational axis (A) of the drill and extending into mortise means (7), with the side surfaces (6) including first surfaces, which are associated with at least some of the bits (3) and are subjected to pressure acting in a rotational direction of the drill during operation of the drill.

Abstract: A rock drill which has a cutting tip of roof-shaped design at its front end is proposed. In order to achieve a reduction in the loading of the carbide cutting tip or an increased drilling capacity in particular in concrete, the flanks are subdivided into flank sections in order to achieve a slimmer embodiment of the drill head.

Abstract: A cutting bit has a bit body which has a forward end and a rearward end. The bit body contains a seat at the forward end thereof. The bit body contains a bore intersecting the seat wherein a bore wall defines the bore. A cutting insert is received by the seat wherein the cutting insert presents a side surface facing the bore. A wedge has a generally longitudinal seating surface. The wedge has a support surface opposite to the longitudinal seating surface. The wedge is received within the bore so that the longitudinal seating surface of the wedge contacts the side surface of the cutting insert and for at least a portion of the length of the wedge the entire support surface contacts the bore wall so as to frictionally retain the cutting insert in the seat.

Abstract: A rotatable cutting bit for penetrating an earth formation wherein the rotatable cutting bit includes an elongate bit body having a forward end and a rearward end. The bit body further defines a peripheral surface. The bit body has a first cutting insert affixed thereto at the axially forward end thereof. The first cutting insert has a first leading cutting edge and a first side clearance cutting edge. The first cutting insert is attached to the bit body so that the first side clearance cutting edge radially extends past the peripheral surface of the bit body so as to engage the earth formation.

Abstract: A method of determining wear characteristics of a rotary drag-type drill bit comprises the steps of: determining the location and shape of a datum profile for the cutters on the bit body: determining the location and shape of a reference profile located inwardly of the datum profile; and ascertaining the volume of superhard material in the cutters between the datum profile and the reference profile. The volume of superhard material in the cutters at discrete radial locations is then plotted against the radial distance of the material from the axis of rotation of the bit body. The predicted wear rate WR.sub.r of superhard material at radius r is also calculated as a function of the volume and the predicted wear rate is plotted against r. The type and location of the cutters may then be modified, if necessary, to give a wear rate which is substantially constant across the radius of the drill bit.

Abstract: A rotatable cutting bit for engaging earth strata wherein the bit comprises an elongate bit body rotatable about a central longitudinal axis. The elongate body has an axially forward end and an axially rearward end. A cutting insert is affixed to the elongate body at the axially forward end thereof. The cutting insert comprises a pair of top surfaces which intersect to form a chisel edge, and a pair of concave surfaces wherein each one of the concave surfaces is adjacent to and intersects its corresponding one of the top surfaces. The cutting insert further includes a pair of end surfaces and a pair of arcuate surfaces. One of the arcuate surfaces intersects the one top surface and further intersects the one end surface whereby the one arcuate surface joins the one top surface and the one end surface. The other of the arcuate surfaces intersects the other top surface and further intersects the other end surface whereby the other arcuate surface joins the other top surface and the other end surface.

Abstract: Drilling tool with a drill head with an end face pointing in the feed direction and which has a main bit, which forms a drill point located in the drill axis and the bit is inclined on either side in a substantially roof-shaped manner and the tool has drilling dust grooves. The main bit has a primary cutting edge, which extends radially over at least one side of the main bit, and a secondary cutting edge, which extends radially over substantially the remaining length of the main bit and is axially set back with respect to the primary cutting edge counter to the feed direction by at least the amount of feed in millimeters per revolution.

Abstract: A cutting bit has a bit body which has a forward end and a rearward end. The bit body contains a seat at the forward end thereof. The bit body contains a bore intersecting the seat wherein a bore wall defines the bore. A cutting insert is received by the seat wherein the cutting insert presents a side surface facing the bore. A wedge has a generally longitudinal seating surface. The wedge has a support surface opposite to the longitudinal seating surface. The wedge is received within the bore so that the longitudinal seating surface of the wedge contacts the side surface of the cutting insert and for at least a portion of the length of the wedge the entire support surface contacts the bore wall so as to frictionally retain the cutting insert in the seat.

Abstract: A rotary roof mine bit for drilling holes in the roof of a mine, comprises a bit body and an insert mounted in the bit body. The insert is formed of a hard material such as carbide or diamond. A top surface of the insert comprises two top sections which intersect a respective main surface of the insert to define first and second non-linear cutting edge. In one embodiment each cutting edge comprises a plurality of mutually angled segments. In another embodiment each cutting edge is continuously curved. Preferably an axial notch is disposed at a center of the top surface.

Abstract: A frustum cutting bit arrangement, including a shank portion for mounting in, and to be retained by, a rotary cutting tool body, the shank portion having an axis, an inner axial end, and an outer axial end. A head portion has an axis coincident with the shank portion axis, a front axial end, and a rear axial end, the rear end coupled to the shank portion outer end, and the front end having a conical cavity therein diminishing in diameter from the front end toward the rear end. A frustum cutting insert has an axis coincident with the head portion axis, a forward axial end, a back axial end, and an outer conical surface diminishing in diameter from the forward end toward the back end, the conical cavity and the outer conical surface having substantially the same taper, the frustum cutting insert fitting into the cavity in a taper lock.

Abstract: A rotary roof mine bit for drilling holes in the roof of a mine, comprises a bit body and an insert mounted in the bit body. The insert is formed of a hard material such as carbide or diamond. A top surface of the insert comprises two top sections which intersect a respective main surface of the insert to define first and second non-linear cutting edge. In one embodiment each cutting edge comprises a plurality of mutually angled segments. In another embodiment each cutting edge is continuously curved. Preferably an axial notch is disposed at a center of the top surface.

Abstract: A rotary drill bit having a head portion with at least two hard surfaced inserts having domed working surfaces and being oppositely oriented to face in the direction of rotation at positive rake angles, and a mounting adapter for removably securing the drill bit to a drilling machine.

Abstract: The present disclosure sets forth various forms of inserts for operating as elements in bearing drill bits and similar devices. A single insert is formed with an external side face of cylindrical construction. One or more strips of hardened materials such as diamond or other hard material are provided along the side face. At the end face, the insert incorporates exposed tungsten carbide, diamond or other hard material. A PDC layer is optionally placed over the end face. The PDC layer has the form of a covering terminating at a radius of curvature.

Abstract: In a rotary earth drill in which sockets are welded to and spaced around a head and drill bits are removably mounted in the sockets, the sockets having a surface exposed to abrasion when the drill is rotated in the earth, a shield in the form of a shroud or jacket is provided, removably mounted on the socket, and extending around the otherwise exposed surface of the socket to protect the socket surface from abrasion. When the shield itself becomes worn, it can easily be removed, in much the way in which the bits are removed, and replaced. In order to accommodate the weld by which the socket is secured to the drill head, the shield is provided with a slot, open at at least one end. The slot is wide enough to permit side edges defining the slot to straddle the weld.

Abstract: A breaking or excavating tool has a diamond and/or cubic boron nitride coated cutting insert mounted at the forward end of a tool body which is made of a softer material than the insert. A separately formed retaining member such as a washer, ring or sleeve, made of harder material than the body, is brazed to a front face of the body surrounding the insert to protect the tool body against wear.

Abstract: A roof drill bit assembly comprising a roof drill bit and a chuck. The roof bit contains a cavity which opens at the rearward end thereof. Upon assembling the bit and the chuck, the cavity receives the axially forward end of the chuck. A sealing member is between the roof drill bit and the chuck so as to provide a fluid-tight connection between the chuck and the roof bit.

Abstract: The invention provides a liner sleeve (8) adapted, in use, to be interposed between the external periphery of a round shank (3) of a point attack, mineral cutter pick (1), and the internal periphery of a circular, shank-receiving bore (5) of a pick box (6), the sleeve (8) being constituted by a plurality of individual rings (14A, 14B, 14C) stacked end-to-end in abutting relationship about a common longitudinal axis (15), the rings (14A, 14B, 14C) together having an axial length (17) approximating to the axial length (12) of the bore (5).

Abstract: A cutting tool for use in excavating an earth formation comprising an elongate tool body having a hard tip being affixed to the forward end thereof. The hard tip has a plurality of integral, coaxial sections including an integral ribbed section which presents a plurality of longitudinal ribs about the circumference thereof. The tip further includes an integral lobed base section which presents a plurality of radially extending lobes. An integral transition region provides a transition between the ribbed section and the base section.

Abstract: A mine tool roof bit insert has two flat parallel sides extending in the long dimension of the insert and has two uppermost slanted surfaces extending between the two flat parallel sides. There is a trough at the top of the insert, which is between the two uppermost slanted surfaces and which is substantially orthogonal to the two flat parallel sides.

Abstract: An insert in accordance with the present invention is attachable to a seat on a mining machine such as a continuous mining machine or a radial longwall. The insert has a cutting face, an inner end, an outer end, and a back adapted to be retained on a seat for retaining an insert. The back of the insert has a protrusion thereon, which may be in the shape of a longitudinal rib, and positioned adjacent each side of the longitudinal rib, a flat. The rib may have any desired cross section, but in the preferred embodiment the rib has an arcuate cross section, or V-shaped cross section. Also a stub on the inner end of the insert fits into a bore in the seat to position the insert during braising.

Abstract: A drill bit is provided which has a novel blade having an elongate longitudinal protrusion positioned axially along the centerline of one side of the blade. The body is adapted to retain the blade in a transverse slot on one end of the body. The slot is provided with a centrally located longitudinal recess along one of the sides of the slot which is adapted to receive the longitudinal protrusion of the blade when the blade is positioned in the slot.

Abstract: This mine roof tool bit insert, formed from a flat elongated body, provides opposed side faces, opposed end faces, a bottom face, opposed top faces and opposed intermediate faces disposed between associated top faces and end faces, the body forming identical halves rotating about a central axis. Each half includes a top cutting edge an intermediate cutting edge and end cutting edge. The top face, intermediate face and end face are planar and are rearwardly inclined to provide a constant relief angle. The intermediate cutting edge is inclined relative to a plane normal of the axis of rotation at an angle greater than that of the top cutting edge. The method of drilling a hole in a mine roof using a bit insert of this character includes positioning the insert, rotating the insert at about 200 to 1000 rpm and applying a thrust of about 1000 to 8000 lbs. to the insert.

Abstract: A two-piece rotatable cutting bit which comprises a shank and a nose. The shank has an axially forwardly projecting protrusion which carries a resilient spring clip. The protrusion and spring clip are received within a recess in the nose to rotatable attach the nose to the shank.

Abstract: A carbide mineral cutting tip (5) comprises a solid carbide body having at least one front face (6), at least one top face (9), a bottom, seating face (12), a rear face (20), and side faces (13), the rear face (20) being provided at the end of an extended tail portion (15) of the tip (5), whereby the front- to-rear length (A to C) of the tip (5) approximates to twice the depth of the tip (5) represented by the top-to-bottom length (D to E) of the front face (6). The invention also includes a mineral cutter pick (1) provided with such a tip.

Abstract: A multi-portion carbide cutting insert which affixes to the forward end of a rotatable cutting bit. The cutting insert has an axially forward tip portion and a flange portion with at least four mediate portions between the tip portion and the flange portion. The first mediate portion has an included angle less than that of the second mediate portion. The second mediate portion has an included angle greater than that of the third mediate portion. The fourth mediate portion has the largest included angle.

Abstract: An insert for mining attack tools comprising a body portion having a longitudinal axis with a head end portion extending outwardly from one end thereof, the body portion having an endless side wall and being sized and shaped for insertion into a socket of an attack tool such that the head end portion extends outwardly from the attack tool for engaging a surface to be mined, the head end portion having a rounded tip end surface portion and an adjacent annular tapered surface portion extending from the endless side wall of the body portion to the tip end portion, and a layer of polycrystalline diamond compact attached to the head end portion of the insert.

Abstract: The invention relates to a tool for breaking or excavating of hard material, such as asphalt. The tool comprises a cutting insert (11) secured to a tool body (10). For purposes maintaining the required cutting force low while ensuring that the risk is low that the cutting insert (11) will get loose the cutting insert (11) is provided with a concave portion (17.sup.1) between the tip portion (12) of the cutting insert and a rear shoulder (13) thereon.

Abstract: A rotatable cutting tool for impacting and fragmenting a substrate. The tool has a tool body containing a valve seat in the forward end thereof wherein a hard insert affixes to the tool body within the valve seat. The hard insert comprises an integral tip segment and an integral axially rearward segment joined to the tip segment by an integral mediate segment. A trio of generally vertically disposed flanges project radially outward from the mediate segment. The flanges are integral with the mediate portion. Each flange presents at least one side surface. During operation, the substrate fragments impinge against the side surface to urge the tool to rotate about its central longitudinal axis.