Abstract: A method has been developed for surface modifications of high temperature resistant alloys, such as FeCrAl alloys, in order to increase their resistance to corrosion at high temperatures. Coating it with a Ca-containing compound before heat-treating builds a continuous uniform and adherent layer on the surface of the alloy, that the aluminum depletion of the FeCrAl alloy is reduced under cyclic thermal stress. By this surface modification the resistance to high temperature corrosion of the FeCrAl alloy and its lifetime are significantly increased.

Abstract: A tool for chip removing machining includes an insert holder and a cutting insert attached thereto. The holder includes a longitudinal center axis and terminates in a support surface at a front end of the holder. The support surface defines a seat to which the insert is removably attached. The support surface forms a 45-degree angle with the center axis. The cutting insert includes a contact surface for mounting the insert to the seat, and a plurality of fingers projecting generally radially with respect to the center axis. Each finger includes a cutting edge and an associated chip surface.

Abstract: A related cutting insert includes a cutting insert body comprising sintering a layer of a superhard material, machining a hole through said sintered layer, brazing said machined layer onto a preformed cemented carbide substrate, and grinding a brazed product to form a cutting insert of predetermined shape.

Abstract: A turning insert includes at least one cutting surface having at least one corner area. The corner area defines a nose angle in the range of 30-85°. The corner area includes a beveled edge. A bisector of the nose angle intersects the beveled edge at a center thereof at a right angle.

Abstract: A tool assembly includes a support body, a clamping device, and a tool holder clamped in a groove of the support body. A stopper block is disposed in the groove and abuts against the tool holder for positioning the tool holder along an axis. The stopper block is held in place by a wedge-type stopper clamp which applies a clamping force to the stopper block in a direction transversely of the axis. A wedge-type holder clamp is provided for applying a clamping force to the tool holder in a direction transversely of the axis. The stopper clamp is secured to the support body by a single fastening bolt, and the holder clamp is attached to the support body by a single fastening bolt. Each of the fastening bolts is provided with a part that forcefully pushes the respective clamp away from the support body in response to loosening of the fastening bolt. The arrangement is such that the tool holder can be inserted and removed without completely removing the holder clamp or its fastening bolt.

Abstract: A method for the production of a heating element that is composed essentially of molybdenum silicide and alloys of that basic material, and a heating element formed from such material. A material is produced that contains substantially Mo(Si1-xAlx)2 and Al2O3 by mixing a molybdenum aluminum silicide Mo(Si1-yAly)2 with bentonite clay in a known manner. The bentonite clay contains impure or contaminating substances with which molybdenum silicide cannot be alloyed and with which the symmetry of the crystal lattice of the molybdenum silicide is retained with a combined content of less than 2000 ppm.

Abstract: A milling cutter for sharpening welding electrodes includes a tool body, and a plurality of cutting inserts fastened to the tool body. The inserts include a center cutting insert and at least two peripheral cutting inserts. Each peripheral cutting insert includes at least one cutting edge. The center cutting insert defines: two oppositely facing principle planes, two cutting edges disposed adjacent respective ones of the principle planes, and a concave surface extending between such cutting edges. The center cutting insert can cut (sharpen) the end surfaces of two welding electrodes simultaneously.

Abstract: A molybdenum silicide type-heating element and a method of manufacturing a heating element of the molybdenum silicide type. The heating element contains substantially Mo(Si1-x Alx)2 and Al2O3 and is prepared by mixing a molybdenum aluminum silicide-type material Mo(Si1-yAly)2 with SiO2, wherein the SiO2 has a purity of at least 98%.

Abstract: A cutting tool for rotary cutting includes a rotatable basic body and a replaceable cutting part or loose top, which is connectable to the basic body via a male/female coupling, which includes a groove and a male part. The groove is formed in a front end of the basic body and is delimited by a bottom surface and two side surfaces. The male part is insertable into the groove along the axis of rotation and protrudes rearwardly from the loose top. The male part has an end surface and two flank surfaces. In the front part of the basic body a forwardly open slot is formed, which separates two elastically deflectable legs wich clamp the male part in the groove. In either the end surface or the bottom surface a recess is formed for receiving a projection on the other surface. The recess is larger than the projection in order to enable the male part to reciprocate a short distance in the groove, whereby the loose top is self-centering with respect to the axis of rotation.

Abstract: A drill rod for percussive rock drilling includes a first rod part and an additional second rod part. The first rod part includes first and second ends, an inner duct, and an external thread disposed adjacent the first end, wherein the external thread is at least partly hardened by heat treatment. The additional rod part includes first and second ends, an inner duct, and an internally thread disposed adjacent the first end thereof, wherein the internal thread is at least partly hardened by heat treatment. The first ends of the respective first and second rod parts are threadedly secured to one another, and the second ends of the respective first and second rod parts are welded together to define a weld zone having a substantially martensitic structure. If there is further provided an intermediate hollow rod part, then the second ends of the respective first and second rod parts would be welded to respective ends of the intermediate hollow part to define weld zones having a substantially martensitic structure.

Abstract: A cutting pick includes an elongate shank, a cutting tip fixed to one end of the shank to project from that end and which is of a material that is harder than the material of the shank, and an annular sleeve which is attached about the shank adjacent the cutting tip. The sleeve is of a material (e.g., tungsten carbide) which is harder than the material of the shank and which has a lower propensity for incendive spark production during a cutting operation than the material of the shank. The sleeve includes a plurality of annular sleeve portions which are attached about the shank immediately adjacent to each other.

Abstract: The present invention relates to a cemented carbide body with the following composition: Co: 10-12 wt-%, TaC: <3 wt-%, NbC: 1-5.5 wt-%, TiC: 3-5 wt-% and as rest WC. The cemented carbide body is particularly useful for metal cutting operations requiring high wear resistance, high edge retention and high edge toughness.

Abstract: A bit head retaining system includes a bit head having an upper end and a working face, and a retention sleeve adapted to be connected to an end of a drill casing and having an internal opening in which at least a portion of the bit head above the working face is disposed, the bit head being secured to the retention sleeve so as to be axially immovable relative to the retention sleeve. A method of installing a bit head in a percussion drill is also disclosed.

Abstract: A cutting insert for milling cam shafts includes first and second surface interconnected by a third surface, and at least one cutting edge. The cutting edge includes a straight first cutting edge section, a straight second cutting edge section, and a generally convex third cutting edge section, all adjoining one another. The first section extends along the junction between the first and third surfaces. The second section extends along the junction and includes a first end adjoining an end of the first section. The second is inclined at an obtuse angle from one end of the first section in a direction away from the third surface. The third section extends along the junction and adjoins a second end of the second section. The third section is of generally convex shape and extends over an angular range greater than 90°. The first, second and third sections lie in the third surface.

Abstract: A screening deck for the screening of crushed stone material includes a plurality of screening elements arranged adjacent one another. At least one side of each screening element is non-parallel with respect to a longitudinal direction of the screening deck. The screening deck includes at least two different types of screening elements which are arranged at different heights in the screening deck for creating narrowing passages and/or winding paths and/or steps for the material traveling on the screening deck.

Abstract: A method of controlling the concentration of nitrogen oxides, hydrocarbons, and carbon monoxide in waste gases. A first lambda value (?1) of the air-fuel mixture is set to less than 1. The gases pass through a first catalyst and then through a second catalyst. The CO-concentration of the gases in the first catalyst is sufficiently high to reduce NOx to N2so that the NOx concentration is reduced to a predetermined value. Oxygen (O2) is introduced between the first catalyst and the second catalyst to oxidize both CO and HC to CO2 and H2O, to reduce the CO-concentration to a predetermined value. A second lambda value (?2) is measured in the gases downstream of the second catalyst, and a valve for regulating the air-fuel ratio is controlled so that the second lambda value (?2) lies within a predetermined range whose lower limit is higher than 1.

Abstract: A shank milling cutter includes a cutting portion which is intended to come into engagement with the workpiece, wherein the envelope surface of the cutting portion is substantially cylindrical. At least one major cutting edge is arranged at the peripheral surface of the cutting portion and at least one minor cutting edge (face cutting edge) is arranged at the end face of the cutting portion and with an end diameter D. The minor cutting edge, in projection onto a plane containing the milling cutter axis, has a convexly curved portion with a radius of curvature R>D/2 and a center of curvature M located such that a distance from the center of curvature M to the axis is in a range from zero to a value smaller than D/2.

Abstract: A rotatable tool for chip removing machining includes a drill shank, and an exchangeable loose top mounted at an axially front end of the shank. Between these there is a coupling, which includes a male part on the loose top, and a groove in the basic body. By means of a slot, two deflectable legs are defined by the shank, which legs form a jaw for receiving and clamping the male part. The maximal width of the jaw upon deflection of the legs away from one another is larger than the maximal breadth of a wedge portion included in the male part. Furthermore, the angles of inclination of flank surfaces on the male part and side surfaces in the groove, are equally large in order to guarantee surface contact between said surfaces, when the legs are resiliently tightened against the male part. The wedge portion is of dovetail shape, wherein the loose top is drawn axially against the shank as it is being radially clamped by the legs.

Abstract: A method of making a cutting insert includes: (i) forming a blank having a substrate and superhard material, the substrate having more than 4 pockets, the superhard material disposed within the pockets; (ii) removing cutting tips from the blank by cutting the blank along cutting lines; (iii) providing a cutting insert body having a plurality of cavities for receiving a corresponding number of cutting tips; (iv) inserting a cutting tip into each of the plurality of cavities; and (v) brazing the cutting tips to the cutting insert body.

Abstract: A method of producing a heating element made from molybdenum silicide and alloys thereof, and which includes aluminum oxide on its surface. A material is produced that contains substantially Mo(Si1-xAlx)2 and Al2O3 by mixing a mixture of a silicon and molybdenum compound with m aluminum compound. Either of the silicon and molybdenum compounds include Mo(Si1-yAly)2 and are mixed with one or both of an aluminum compound in the form of Al2O3 or Al(OH)3 and optionally the compounds SiO2, Si, and MoO3, or by virtue of the mixture of the silicon and molybdenum compound containing MoO3 and Al and Si and/or SiO2. The input components together have a degree of purity corresponding to at least 98%. The mixture reacts exothermically and/or by being sintered, so that exchange reactions take place to form the compounds Mo(Si1-xAlx)2 and Al2O3, where x lies in the range of 0.4-0.6.