Abstract: A diamond-bearing assembly comprises opposed diamond-bearing surfaces, at least one of which is free of any Group VIII metals such as cobalt. Preferably, each of the surfaces is provided by a surface of a diamond compact, such diamond compact containing substantial diamond-to-diamond bonding, and a second phase which contains silicon in the form of silicon and/or silicon carbide.

Abstract: A composite diamond abrasive compact comprises a diamond compact bonded to a cemented carbide support along a compact/carbide interface and is characterised by the carbide support comprising at least two zones, a first zone containing a binder metal content of a predetermined amount, and a second zone extending from the interface to the first zone and having a binder metal content which is substantially lower than that of the first zone. The second zone has a depth or thickness of no more than 0,75 mm. The binder metal content of the second zone increases from the interface to the first zone in a continuous, non-interrupted manner.

Abstract: The wire saw including a rope, abrasive beads spaced longitudinally apart on the rope by elastic spacers and elastic sleeves, one for each bead, sandwiched between the respective beads and the rope. The sleeves are conveniently made of rubber which is vulconized to the rope and to the beads.

Abstract: A method of producing a composite diamond abrasive compact includes the steps of forming an unbonded assembly comprising a cemented carbide body, a layer of catalyst metal on a surface of the carbide body, a layer of carbide particles, alone or in admixture with other particles, on the catalyst metal layer, and a layer of diamond particles on the carbide layer and subjecting the unbonded assembly to conditions of elevated temperature and pressure at which diamond is crystallographically stable to form a composite diamond abrasive compact.

Abstract: A saw comprises a support such as a metallic disc-shaped blank and a working portion bonded to the periphery of the blank. The working portion comprises a mass of abrasive particles held in a polymeric matrix and has a bonding surface through which it is bonded to the support and a working surface. Examples of suitable polymeric matrices are rubber, polyurethane and nylon.

Abstract: A wire saw comprises a wire rope to which a plurality of cutting elements are secured in spaced relationship along its length. The cutting elements comprise a cylindrical metal sleeve, the central portion of which is swaged so that the inner surface grips the rope securely. Brazed to each end of the sleeve is a ring of a thermally stable diamond compact. The edges of the rings provide cutting edges for the element.

Abstract: A cutter pick for a mining machine has a lug carrying a cutting tip of hard, abrasion resistant material at its forward end. A passage extends through the lug with provision at its rearward end for connection to a source of high pressure liquid and with a nozzle at its leading end venting through the cutting tip. The intention is that high pressure liquid issueing from the nozzle will degrade the rock before it is attacked by the cutting tip.

Abstract: A cutting tool for a mining machine comprises a holding lug for connecting the tool to the mining machine, and a tool component. The tool component comprises a cemented carbide stud having a bottom portion, a top conical portion in which is provided a top recess and a central portion spacing the top portion from the bottom portion. The bottom portion and the whole of the central portion are secured within a socket formed in one end of the holding lug. The top conical portion lies wholly within the space bounded by an imaginary upward continuation of the upper edge of the end of the holding lug. The tool component also includes a composite abrasive compact secured within the top recess, the composite abrasive compact comprising a cemented carbide backing to which is bonded a compact layer. The periphery of the compact layer provides a cutting edge for the tool component.

Abstract: The invention relates to abrasive tools such as a cutting tool for a mining machine. Located in a socket 18 of the tool is a cutting insert comprising an elongate pin 22 having a bottom conical end 24 located in the recess and a top control portion 26 to which is bonded a composite abrasive compact. The composite abrasive compact having an abrasive compact layer 34 bonded to a cemented carbide substrate 36. The socket 18 complements the shape of the elongate pin 22 and, in particular, the bottom conical end 24. This arrangement minimizes the occurrence of stress raisers.

Abstract: Thermally stable abrasive compacts of hexagonal shape have been found to have excellent abrasive properties in the abrading of a medium to soft rock having an unconfined compressive strength of less than 240 MPa. Preferably the abrasive tool used is a surface set drill bit wherein some of the thermally stable abrasive compacts are so located around the working edge of the bit that a side thereof acts as a gauge stone for the working portion.

Abstract: A cutting component comprising:(a) a composite abrasive compact comprising an abrasive compact bonded to a cemented carbide support;(b) an elongate, cylindrical pin having end surfaces and a side surface;(c) a recess for receiving the composite abrasive compact sloping from one end surface of the pin to the side surface;(d) the composite abrasive compact being located in the recess and bonded to the pin such that the abrasive compact presents a cutting edge for the cutting component and the abrasive compact lies wholly within the side surface of the pin and an imaginary extension thereof; and(e) a groove in the recess which spaces the abrasive compact from the pin.

Abstract: A spring clip which is used to secure the shank of a cutting pick to a pick box or cutting drum in a mining machine. The clip is formed of spring steel and has spaced legs joined by a bight portion. Associated with the bight portion is a bearing part which bears upon the shank of the cutting pick when the clip has been aligned with the shank and has been forced transversely to the shank so that the shank is received between the legs.

Abstract: A method of bonding a cemented carbide surface to a metal surface is provided. The method involves applying an alloy layer to one or both of the surfaces, the alloy comprising a major amount of nickel or copper and a minor amount of phosphorus, heat treating the alloy layer below its liquidus temperature to cause it to diffusion bond to the surface top to which it is applied and bonding the surfaces together by means of a solder or braze alloy which preferably has a liquidus of no more than 750.degree. C. The method has particular application to bonding cutting inserts to drill bits and cutting tools for mining machines.

Abstract: A tool component is provided which has particular application in the cutting tool of a mining machine for cutting a variety of soft materials such as coal. The tool component has an elongate stud 12 and a composite abrasive compact 14 located in a recess 20 formed in one end thereof. The recess and composite abrasive compact are surrounded by a shoulder portion 22 which provides, in use, a protective surface for the cutting tool.

Abstract: The invention provides an abrasive body which will generally be of cylindrical shape comprising a plurality of superhard abrasive particles such as diamond bonded together by means of a tough wear-resistant nickel based alloy having a melting point of below 1000.degree. C. These alloys are known as hard facing alloys. The abrasive bodies may be used as inserts for drill crowns. The bodies are made by mixing the abrasive particles with the alloy in powdered form, producing a green-state, coherent body from the mixture, generally by cold pressing, and sintering the green-state product under conditions which inhibit degradation of the abrasive particle.