Abstract: A method of removing the binder phase from the surface of a hard material body consisting of hard constituents in a binder phase based on cobalt and/or nickel and with a binder phase enriched surface zone is disclosed. By carrying out a blasting process using particles with a size of 400-1500 mesh, a favorable combination of even removal of the cobalt layer, essentially no damage to the carbide grains and reasonable blasting time is obtained.

Abstract: Button inserts of a rock drilling bit are ground by positioning a grinding cup against each button insert and rotating the cup while supplying flushing fluid thereto. The flushing fluid is conducted through an axial bore of a spindle on which the grinding cup is mounted. An inner end of the spindle is mounted for rotation in a grinding head, and is rotated by a drive mechanism disposed within the grinding head. Flushing fluid is supplied to the axial bore through a flushing head mounted on the spindle at a location outside of the grinding head. The flushing head has axially spaced parts that are movable axially relative to one another under the force of flushing fluid passing therethrough, in order to establish a fluid seal.

Abstract: Handle for tools such as screwdrivers, cormprising a core of hard plastic material around a metal shaft and a gripping surface (14) of soft material covering parts of the core, where the core within the regions covered by the gripping surface is made with a multitude of protruding lower blocks (17) with flat tops, and the soft material filling the space between lower blocks to the level of the tops of lower blocks (17) to form base surface (16) and a multitude of blocks (15) raised from the base surface, arranged in a repetitive pattern with voids where the lower blocks protrude.

Abstract: The present invention relates to a sintered body of titanium-based carbonitride alloy comprising hard constituents containing at least tungsten in addition to titanium in a binder phase based on cobalt. There are four distinctly different microstructural components, namely: A) cores which are remnants of and have a metal composition determined by the raw material powder; B) tungsten-rich cores formed during the sintering; C) outer rims with intermediate tungsten content formed during the sintering; and D) a binder phase of a solid solution of at least titanium and tungsten in cobalt. Toughness and wear resistance are varied by adding WC, (Ti,W)C, and/or (Ti,W)(C,N) in varying amounts as raw materials.

Abstract: In an air actuated down-the-hole hammer for rock drilling, a piston reciprocates within a casing to impact against a rear anvil surface of a drill bit. A foot valve extends axially between the piston and the drill bit. The anvil surface is inclined downwardly in a radially outward direction to cause liquid on the anvil surface to be discharged in a direction away from the foot valve, to prevent damage to the foot valve which could occur if piston impacts were able to create high-speed liquid streams contacting the foot valve.

Abstract: An indexible cutting insert for chip-breaking metal machining comprises an upper surface or chip surface, a lower bottom surface which is substantially plane parallel to the upper surface, and at least a side surface extending between the surfaces, which forms an acute angle with the upper surface and an obtuse angle with the bottom surface. The side surface has at least two bulging portions which are intended to function as support surfaces against the support surfaces in an insert seat.

Abstract: The present invention relates to a cutting insert for a rock drill bit. The rock drill bit includes a tool body (10) having a front surface (13), and a number of cutting inserts (14), each having a generally cylindrical shank portion. The cutting insert (14) is provided with increased volume portions in its parts being most subjected to wear. The invention also relates to the rock drill bit.

Abstract: A cutter tool comprises a tool holder, a cutting bit mounted in a bore of the tool holder, and a washer disposed between the tool holder and the cutting bit. The washer is a conical (Belleville) washer which makes annular line contact with a shoulder of the cutting bit, and with an edge of the bore of the tool holder, in order to effectively seal-out fines from the bore.

Abstract: A drilling tool for boring in earth and rock formations includes a pilot bit which defines a longitudinal tool axis and includes a cam part having a cam axis arranged eccentrically relative to the tool axis. A reamer includes a hollow reamer body mounted on the cam part for rotation relative thereto about the cam axis. Relative rotation in one direction causes the reamer to be radially extended, and relative rotation in an opposite direction causes the reamer to be radially retracted. The reamer body carries cutting elements for enlarging a hole drilled by the pilot bit when the reamer is in its extended position. The cam part carries a first removable insert on which a first stop surface is formed. The reamer carries a second removable insert on which a second stop surface is formed. The stop surfaces are engageable with one another when the reamer body is radially extended, for transmitting rotational cutting forces to the reamer.

Abstract: In order to consolidate soil, a hole is drilled therein by advancing downwardly through the soil a rotary percussive drill bit disposed at the end of a drill string. Water is pressurized at the ground surface and is conducted to actuate a hydraulically driven down-the-hole hammer disposed above the drill bit. While vertically retracting and rotating the drill string, grout, which is pressurized at the ground surface, is conducted downwardly through the drill string and ejected laterally outwardly through a lateral opening in the drill string to produce a console of mixed soil and grout surrounding the hole. The water and grout are pressurized in respective chambers of a pump.

Abstract: There is disclosed a method of producing, in large volume and at low cost, titanium carbide, nitride and carbonitride whiskers, with preferably submicron diameters, to be used as reinforcing material. The whiskers are suitable for use as a reinforcement material in a wide range of materials, including metals, intermetallics, plastics, ceramics and metallic bonded hard material. Titanium oxide, hydroxide or alkali compounds thereof are mixed with a carbon source with a volatile part which volatiles at temperatures exceeding 500.degree. C. and in an amount to satisfy the stoichiometric requirements of the carbide or nitride. A halogenide salt is used as a volatilization agent for titanium as well as a catalyst able to dissolve Ti plus C and/or N, such as Ni or Co. The reactant powders are blended in some typical manner, e.g., by using a high speed blender so as to intimately mix them.

Abstract: The present invention relates to a partially enhanced drill bit (10') for percussive drilling. The bit comprises a bit body, at least one annular row of non-enhanced buttons (11') mounted in the bit body; and at least one annular row of enhanced buttons (12') mounted in the bit body radially outside of the non-enhanced buttons. At least one annular row of non-enhanced buttons (11') and said at least one annular row of enhanced buttons (12') are provided to partly overlap each other. There is an axial shoulder (19') radially outside of the non-enhanced buttons (11'). There are chamfers (20') at least partly surrounding the enhanced buttons (12'). These chamfers (20') interrupt the shoulder (19') in the circumferential direction.

Abstract: The present invention relates to a cutting tool comprising a body of sintered cemented carbide or cermet, ceramic or high speed steel on which at least one of the functioning parts of the surface of the body, a thin, adherent, hard and wear resistant coating is applied. The coating comprises a laminar, multilayered structure of refractory compounds in polycrystalline, non-repetitive form, MX/NX/MX/NX where the alternating layers MX and NX are metal nitrides or carbides with the metal elements M and N selected from the group consisting of Ti, Nb, Hf, V, Ta, Mo, Zr, Cr, Al and W. The sequence of individual layer thicknesses is essentially aperiodic throughout the entire multilayered structure, and layer thicknesses are larger than 0.1 nanometer but smaller than 30 nanometer, preferably smaller than 20 nanometer. The total thickness of said multilayered coating is larger than 0.5 .mu.m but smaller than 20 .mu.m.

Abstract: A rock drill for percussive drilling includes a shank, a collar connected to a front end of the shank, and a rod portion which at one end connects to the collar while the other end carries a rock cutting means. A central flush channel extends from the front free end of the shank in a direction towards the front end. The central flush channel has a substantially constant diameter (d) along essentially its entire length; a ratio of the diameter (d) to a smallest outer cross sectional width (D) of the rod portion being in the range of 0.35 to 0.43.

Abstract: A composite roll including one or more rings of cemented carbide metallurgically bonded to a cast iron casing. The composite roll may be used for hot or cold rolling. The cast iron has the following composition in addition to Fe, in weight %, 1.9-2.8% Si, 0.02-0.10% Mg, 0.5-4% Ni, 0.1-1% Mn, balance Fe and a C.sub.eqv =2.5-6.

Abstract: A rock drilling rod is manufactured by placing free ends of first and second hollow rod components in abutment, and establishing relative rotation between the free ends to friction weld those free ends together. The first component comprises a thread and a clearance portion disposed adjacent the thread. The first component has a hot hardness value of at least about 170 HV1 at 600.degree. C. Prior to friction welding the components together, the thread, clearance portion and central passage of the first component are heat treated against corrosion fatigue. Then, the thread is high frequency hardened to a depth at least as great as the heat treated layer. Following the welding, the weld is cooled while keeping a core hardness of the respective portions of the first and second components disposed immediately adjacent the weld no lower than 390 HV1.

Abstract: A handle for tools such as screwdrivers where an end region is shaped as a smooth rounded surface and made by injection molding in multiple steps from at least two differently colored plastic materials, which are tactilely indistinct, to form a visible marking for identification of the tool.

Abstract: A multilayer coated cutting tool comprising a cemented carbide body with at least one sintered-on inlay containing polycrystalline cubic boron nitride forming at least one cutting edge. Reduced crater wear of the rake face of the tool is achieved by reducing chemical interaction between tool and workpiece/chip material, and used edges of indexable inserts can be readily identified. The tool is provided with a multilayer coating by thermal CVD, the coating including (1) a first, innermost, layer of TiC.sub.x N.sub.y O.sub.z with x+y+z=1, with y>x and z<0.2, with equiaxed grains with size <0.5 .mu.m and a total thickness <1.5 .mu.m, (2) a second layer of TiC.sub.x N.sub.y O.sub.z with x+y+z=1, preferably with z=0, x>0.3, most preferably x>0.5, having a thickness of 1-8 .mu.m, with columnar grains, and (3) a third layer of a smooth, fine-grained (grain size about 1 .mu.m) layer of (.alpha.-Al.sub.2 O.sub.3 or .kappa.-Al.sub.2 O.sub.3 or mixtures thereof, with a thickness of 2-10 .mu.m.