Abstract: A chain saw guide bar allowing spraying of the cut surface of a stump with liquid, is made from three joined plates with a spraying device comprising one or more supply channels provided as cutouts in the central plate. A plurality of spraying holes are provided in one or both side plates. The spraying holes are offset towards the guide bar edge so far that less than the entire area of spraying hole area overlaps the edge of the supply channel.
Type:
Grant
Filed:
January 21, 1994
Date of Patent:
June 27, 1995
Assignee:
Sandvik AB
Inventors:
Arvo Leini, Karl O. Pettersson, Per-Olof Lofgren, Staffan Lindberg
Abstract: A cutting insert for chip forming machining of workpieces is disclosed. The insert includes at least one end-positioned cutting head having an upper surface with a cutting edge extending across the width of the cutting insert and the ends of the cutting edge adjoining front chip surface side portions. A chip-deforming depression is provided between the front chip surface side portions. The rake angle of the chip surface side portions is consistently negative while the rake angle of a surface of the depression adjacent the cutting edge is consistently positive.
Abstract: The present invention relates to a drill comprising a shaft with chip-conveying flutes and a drill head with two or more cutting elements. Each of the cutting elements comprises a cutting edge which is delimited between a chip-breaking surface and a relief surface and which, at least in the proximity of the geometrical center or rotational axis of the drill, comprises a curved portion. The cutting edge of the individual cutting elements is located with its curved portion in such a way that a tangential point on a straight line that extends from the central axis and tangentially touches said curved edge portion, is provided distantly from the central axis of the drill. In the immediate proximity of this central axis, the cutting edge is terminated in a small material portion which is common for all cutting edges and which extends between the cutting elements in order to serve for centering the drill.
Abstract: The present invention relates to a sintered titanium-based carbonitride alloy for milling and turning where the hard constituents are based on Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and/or W and the binder phase based on Co and/or Ni. The structure comprises 10-50% by volume hard constituent grains with core-rim-structure with a mean grain size for the cores of 2-8 .mu.m in a more fine-grained matrix with a mean grain size of the hard constituents of <1 .mu.m and where said mean grain size of the coarse hard constituents grains is >1.5 .mu.m, preferably >2 .mu.m, larger than the mean grain size for the grains in the matrix. The coarse grains can be Ti(C,N), (Ti,Ta)C, (Ti,Ta)(C,N) and/or (Ti,Ta,V)(C,N).
Type:
Grant
Filed:
May 6, 1992
Date of Patent:
June 6, 1995
Assignee:
Sandvik AB
Inventors:
Rolf G. Oskarsson, Gerold Weinl, Ake Ostlund
Abstract: A cutting insert is produced by form-pressing and sintering of powder. The insert comprises a top chip surface, a bottom surface, and at least one edge surface extending between the top and bottom surfaces. The edge surface includes at least one relief surface portion which intersects the top surface at an acute angle to form therewith a cutting edge. A grinding operation is performed on the edge surface, but only along a lower portion thereof disposed below the relief surface portion, i.e., only along an area which is to be placed against a locating surface of a machine tool during a cutting operation.
Abstract: There is now provided a method of manufacturing a coated ceramic body with improved performance when used as a tool insert for metal cutting purposes. By subjecting the body after the coating to a hot isostatic pressing operation at a pressure of 10-300 MPa and a temperature of >1200.degree. C., an improved adherence of the coating has been achieved. The method is particularly applicable to whisker-reinforced ceramic composites.
Abstract: There is now provided an oxide-based, preferably aluminum oxide based, matrix with 5-50, preferably 10-40% by volume of homogeneously dispersed whiskers based upon nitrides, carbides and/or borides of metals from group IVB (Ti,Zr,Hf) and/or VB (V,Nb,Ta) of the periodic system or solid solutions thereof and 1-20, preferably 3-8% by volume of particulate additions with a size <500 nm, preferably <200 nm, based upon carbides, nitrides and/or borides of metals from group IVB (Ti,Zr,Hf) and/or VB (V,Nb,Ta) of the periodic system or solid solutions thereof. The nanosize particulate additions are predominantly present inside the matrix grains and not in the grain boundaries.
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: There is provided a cemented carbide roll for rolling metal strips and wire flattening containing WC and with a binder that comprises at least one of the metals Co, Ni or Fe. Moreover, it consists of a core of eta-phase containing cemented carbide surrounded by an eta-phase free surface zone on the rolling surface of the roll and with the sides of the roll comprising exposed eta-phase.
Abstract: There is now provided a ceramic cutting tool material comprising a ceramic, preferably aluminum oxide based, matrix with 5-50%, preferably 10-40%, by volume of homogeneously dispersed SiC-whiskers and 1-20%, preferably 3-8%, by volume of particulate additions with a size <500 nm, preferably <200 nm, based upon carbides and/or nitrides and/or borides of metals from group VB (V,Nb,Ta) in the periodic system or solid solutions thereof. The nanosize particulate additions are predominantly present inside the matrix grains and not in the grain boundaries.
Abstract: A cemented carbide button for rock drilling comprises a core and a surface zone surrounding the core whereby both the surface zone and the core contains WC (alpha-phase) and a binder phase based on at least one of Co, Ni, or Fe and the core in addition contains eta-phase. The eta-phase core extends to the very top (working) surface of the button and as a result is obtained longer life and higher drilling rate particularly for rotating crushing drilling, cutting drilling and percussive drilling in soft rocks.
Type:
Grant
Filed:
November 13, 1992
Date of Patent:
May 9, 1995
Assignee:
Sandvik AB
Inventors:
E. Torbjorn Hartzell, Udo K. Fischer, Jan Akerman
Abstract: A cut-of tool comprises a thin holder plate of steel, and a cutting insert of cemented carbide. The holder plate has an outwardly opening, insert-receiving recess defined by a bottom wall, an inner wall and an upper wail which is part of an elastically movable clamping arm serving to retain the insert in the recess. The insert has both upper and lower grooves of V-shaped cross-section, which are adapted to cooperate with corresponding V-shaped ridges associated with the recess. Between the insert and the bottom wall of the recess, there is provided a dismountable spacer element of cemented carbide, which has on its upper side a V-ridge for engaging a corresponding V-groove in the underside of the insert. The spacer element is maintained in place, on the one hand, by a countersunk connecting device in the area of the outer end of the bottom wail and, on the other hand, by a male-female connection between the inner wall of the recess and a rear end of the element.
Abstract: The invention relates to a high strength, vanadium-containing stainless steel alloy in which the amounts of the alloy elements have been balanced such that the austenite phase remains stable without being deformed into martensite even under large reductions. The steel alloy comprises 0.04-0.25 % C, 0.1-2 % Si, 2-15 % Mn, 16-23 % Cr, 8-14 % Ni, 0.10-1.5 % N, 0.1-2.5 % V, the remainder being iron and normal impurities.
Abstract: Method of manufacturing a sintered carbonitride alloy comprising wet milling powders of forming binder phase containing Co, Ni and mixture thereof and powder forming hard constituents of nitrides and carbonitrides with Ti as the main component to a mixture with desired composition; compacting said mixture to form compact; heating the compact at 100-300 C. in oxygen or air and subjecting said compact in multiple heating steps to effect sintering.
Type:
Grant
Filed:
February 10, 1994
Date of Patent:
April 4, 1995
Assignee:
Sandvik AB
Inventors:
Gerold Weinl, Rolf G. Oskarsson, Per Gustafsson
Abstract: There is provided a cemented carbide tool for punching, cutting or nibbling containing WC and a binder comprising at least one of the metals Co, Ni and Fe. The tool comprises a core of eta-phase-containing cemented carbide surrounded by an eta-phase-free surface zone with the working surface of the tool comprising exposed eta-phase-containing cemented carbide.
Abstract: Method of making sintered insert for milling and turning formed of a titanium-based carbonitride containing hard constituents and binder phase metal comprising milling at least one hard constituent with binder phase metal, adding a second hard constituent at a later time during milling, pressing and sintering the pressed constituents to form the insert.
Type:
Grant
Filed:
May 6, 1992
Date of Patent:
April 4, 1995
Assignee:
Sandvik AB
Inventors:
Rolf G. Oskarsson, Gerold Weinl, Ake stlund
Abstract: The present invention relates to cemented carbide bodies preferably for wear demanding rock drilling and mineral cutting. The bodies are built up of a core of eta-phase-containing cemented carbide surrounded by a surface zone free of eta-phase where the binder phase content in the outer pan of said zone is lower than the nominal and, in addition, constant or near constant, and the binder phase content in the inner part of the eta-phase free zone closer to the eta-phase core is higher than the nominal. According to the method of the invention, bodies comprising evenly distributed eta-phase are subjected to a partly carburizing treatment with a carbon activity, a.sub.c, close to 1.
Type:
Grant
Filed:
September 22, 1993
Date of Patent:
March 28, 1995
Assignee:
Sandvik AB
Inventors:
E. Torbjorn Hartzell, Jan Akerman, Udo K. R. Fischer
Abstract: A mounting base for chain saw guidebars, comprising a plate (11) with a slot (14) in which a guide piece (36) can slide in the lengthwise direction of the guidebar, said guide piece being acted on by one or more pistons (17) energized by a self-contained pressure source (19) preferably comprising a gas spring, and a valve device (18) which can be set in different positions, during sawing urging the guidebar outwards with a predetermined force and preventing displacement inwards, and during changing of saw chain or guidebar permitting displacement inwards of the guidebar while preventing the pistons (17) from urging the guidebar outwards.