Abstract: The present invention relates to a rock bit insert of cemented carbide for cutting rock drilling. The insert is provided with one or more bodies or layers of diamond or cBN produced at high pressure and high temperature in the diamond or cBN stable area.The body of cemented carbide has a multi-structure containing eta-phase surrounded by a surface zone of cemented carbide free of eta-phase and having a low content of cobalt in the surface and a higher content of cobalt next to the eta-phase zone.

Abstract: The present invention relates to a rock bit button of cemented carbide for percussive or rotary crushing rock drilling. The button is provided with one or more bodies of polycrystalline diamond in the surface produced at high pressure and high temperature in the diamond stable area. Each diamond body is completely surrounded by cemented carbide except the top surface.

Abstract: A composite for cutting in subterranean formations comprises a cemented carbide substrate and a diamond layer adhered to a surface of the substrate. That surface includes a plurality of spaced apart ridges forming grooves therebetween. The diamond layer has a thickness greater than a depth of the grooves and occupies the grooves to interlock with the substrate. The diamond is comprised of a substantially uniform distribution of diamond particles having a grain size in a range of about 25-75 microns. The ridges are spaced radially inwardly from an outer periphery of the substrate, whereby the diamond layer includes an annular ring portion completely surrounding the plurality of ridges to provide radial reinforcement against the formation and propagation of cracks tending to occur in the vicinity of the ridges.

Abstract: A cutting element has a V-shaped diamond cutting face. The cutting element is formed from a single circular cutting blank by cutting the blank into segments, joining two identical ones of the segments, and truncating the joined segments.

Abstract: A cutting element comprises a stud and a composite bonded thereto. The composite comprises a substrate formed of cemented carbide, and a diamond layer bonded to the substrate. The interface between the diamond layer and substrate is defined by alternating ridges of diamond and cemented carbide which are mutually interlocked.

Abstract: A cutting element of the type which is pushed into a preformed hole of a drill bit by means of a pusher tool. The cutting element comprises a generally cylindrical stud having an inclined support face adjacent a forward end of the stud. A polycrystalline diamond substance is disposed on the support face. A non-circular tool recess is formed in the forward end of the stud and behind the support face and is configured to receive a pusher tool for confining pushing forces to the region of the recess as the cutting element is pushed into the preformed hole. The cutting element can also be rotated by the tool for repositioning the cutting element after installation, or loosening the cutting element to facilitate its removal.

Abstract: A rotary drill bit comprises a bit body carrying a plurality of cutting elements and a main conduit for conducting drilling fluid. A plurality of nozzle bodies is rotatably seated in bores of the bit body. Each nozzle body includes a plurality of passages extending therethrough for conducting drilling fluid in such manner that the exiting fluid causes the nozzle body to rotate about its longitudinal axis. The exiting fluid is thus distributed in a wider pattern.

Abstract: A cutting element includes a stud having an inclined supporting surface. The supporting surface intersects a side surface of the stud to form an edge. A cutting member is bonded to the supporting surface. A reinforcing shoulder projects from the supporting surface adjacent a rear portion of the cutting member. The shoulder includes a side surface, a portion of which intersects the edge along a region of the edge whose forwardmost point is spaced rearwardly from a rearwardmost point of the cutting member. When the cutting element is positioned within a bore of a drill bit, that region of the edge is completely positioned within the bore so as to be reinforced by the bore wall.

Abstract: A cutting element for use in rotary drill bits comprises a generally cylindrical stud and a cutting disk bonded to a supporting surface of the stud. The supporting surface intersects a cylindrical side surface of the stud to form an edge. The supporting surface includes a plurality of alternating projections and grooves extending in a front-to-rear direction of a supporting surface. The projections and grooves include rear ends terminating short of the edge to minimize the formation of stress cracks in the edge.

Abstract: A cutting element comprises a stud and a cutting blank bonded to a mounting face of the stud. The stud comprises stiffening elements of a refractory carbide embedded in a body of steel. The mounting surface is formed partially of carbide and partially of steel, and the cutting blank is bonded to the steel and carbide.

Abstract: An abrasive compact is made by a method comprising the steps of providing a circular cylindrical substrate having an upper with a non-circular recess therein defined by non-intersecting side walls. The recess is filled with diamond grains and is positioned in a press. The substrate and diamond grains are subjected to high temperature and pressure conditions in the press to sinter the diamond grains and bond the sintered diamond grains to the substrate in the form of a non-circular diamond layer. The portions of the substrate not covered by the diamond layer are removed.

Abstract: A rotary drill bit includes a cutting face having a peripheral edge and a central recess. A plurality of fluid discharge nozzles are mounted in bores in the cutting face. A plurality of cutter elements are mounted in the peripheral edge and in the recess to fracture an earthen core formed as the drill cuts through a formation. A plurality of lateral discharge passages extend radially through the bit body from said recess and extend longitudinally to the peripheral edge to form circumferential interruptions in the peripheral edge. Each passage includes leading and trailing edges at the cutting face. A convex protrusion is disposed centrally at a longitudinally inner end of the recess and includes a convex deflecting surface arranged to contact and fracture the earthen core and deflect the cuttings to the lateral discharge passages. The outer periphery of the cutting face is radially recessed to accommodate the flow of drilling fluid.

Abstract: A cutting blank, preferably for use on a drill bit for cutting through earth formations, comprises a substrate formed of a hard material and including a cutting surface. A plurality of shallow grooves are formed in the cutting surface and each groove includes opposing side and base portions. Strips of a diamond substance are disposed in the grooves and are adhered to the side and base portions and include a cutting face exposed adjacent to the cutting surface of the substrate. The strips may be arranged in various patterns and may be in non-intersecting relationship, or intersecting relationship. The grooves may include undercut portions to more positively anchor the strips to the substrate. The cutting blank is preferably bonded to a stud, with the stud being mounted in a rotary drill bit.

Abstract: A rotary drill bit includes a cutting face having a peripheral edge and a central recess. A plurality of fluid discharge nozzles are mounted in the cutting face. A plurality of cutter elements are mounted in the peripheral edge and in the recess to fracture an earthen core formed as the drill cuts through a formation. A plurality of lateral discharge passages extend radially through the bit body from said recess and extend longitudinally to the peripheral edge to form circumferential interruptions in the peripheral edge. A convex protrusion is disposed centrally at a longitudinally inner end of the recess and includes a convex deflecting surface arranged to contact and fracture the earthen core and deflect the cuttings to the lateral discharge passages.

Abstract: A method for dressing a grinding wheel, comprising the step of engaging the periphery of a rotating grinding wheel with a dressing tool composed at a positive back rake angle and optionally at a positive side rake angle. The dressing tool is preferably comprised of a composite compact having a first layer of bonded abrasive crystals of diamond or CBN and a second layer of cemented tungsten carbide bonded to the first layer. The compact may be provided with a side cutting edge angle between 0.degree. and 90.degree. and an end edge cutting angle between 0.degree. and 45.degree..

Abstract: One or more masses of bonded particles of diamond, cubic boron nitride (CBN), and wurtzite boron nitride (WBN) are sandwiched between or encapsulated by two masses of cemented carbide bonded to the particle masses. In the preferred embodiment, the particle masses are comprised of (1) at least 70% by volume of said particles, and (2) a metallic phase comprised of the cementing agent of the carbide mass. The composite compacts find utility in drill bit, mining tool and wear part applications.A method for making such a composite compact comprises (1) placing within a reaction cell masses of abrasive particles and at least two carbide masses interleaved with the abrasive particle masses, (2) the masses are placed in the cell in such a manner to allow for the accommodation of pressure and (3) simultaneously subjecting the cell and the contents thereof to temperature and pressure conditions at which the particles are stable.

Abstract: Composite compacts comprising a cluster of abrasive particles selected from among diamond, cubic boron nitride and wurtzite boron nitride on a support medium, are securely bonded to metal tool parts by a process comprising providing a bond initiator between, and in contact with, a surface of the composite compact and a surface of the tool part, passing a short duration, high electrical current pulse through the contacting surfaces sufficient to cause melting of the bond initiator without raising the temperature of the abrasive particles to their decomposition temperature, forcing the composite compact and tool part together under an applied magnetic force pulse while the bond initiator is molten, and recovering the article.