EP0548163B1 - Selbstschärfendes schneidelement für bohrmeissel - Google Patents

Selbstschärfendes schneidelement für bohrmeissel Download PDF

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Publication number
EP0548163B1
EP0548163B1 EP91916192A EP91916192A EP0548163B1 EP 0548163 B1 EP0548163 B1 EP 0548163B1 EP 91916192 A EP91916192 A EP 91916192A EP 91916192 A EP91916192 A EP 91916192A EP 0548163 B1 EP0548163 B1 EP 0548163B1
Authority
EP
European Patent Office
Prior art keywords
grooves
cutting edge
bit according
support
self
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP91916192A
Other languages
English (en)
French (fr)
Other versions
EP0548163A1 (de
Inventor
Alain Besson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
TotalEnergies SE
Original Assignee
Total SE
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Filing date
Publication date
Application filed by Total SE filed Critical Total SE
Publication of EP0548163A1 publication Critical patent/EP0548163A1/de
Application granted granted Critical
Publication of EP0548163B1 publication Critical patent/EP0548163B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
    • E21B10/56—Button-type inserts
    • E21B10/567—Button-type inserts with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts
    • E21B10/5673—Button-type inserts with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts having a non planar or non circular cutting face
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/006—Drill bits providing a cutting edge which is self-renewable during drilling
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
    • E21B10/56—Button-type inserts
    • E21B10/567—Button-type inserts with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts
    • E21B10/573—Button-type inserts with preformed cutting elements mounted on a distinct support, e.g. polycrystalline inserts characterised by support details, e.g. the substrate construction or the interface between the substrate and the cutting element
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/62—Drill bits characterised by parts, e.g. cutting elements, which are detachable or adjustable

Definitions

  • the present invention relates to an oil or mining drilling tool according to the preamble of claim 1.
  • the support can be constituted by a stud, crimped in the body of the tool, or on a tungsten carbide matrix.
  • the increased force applied to the tool may cause partial destruction or loss of the cutting edges by heating.
  • Patent EP-A-0 363 313 describes a tool comprising rupture zones formed on elements which, by breaking, make it possible to enlarge the openings for the passage of a lubricating liquid.
  • the object of the present invention is to remedy these drawbacks by proposing self-sharpening cutters, that is to say which are liable to break along surfaces having favorable orientations, each time the force applied to the tool becomes greater than a given threshold.
  • the subject of the invention is a drill bit cutter according to the characterizing part of claim 1.
  • the clearance angle is preferably between 25 and 55 °.
  • the tool 10 comprises a steel body 12 carrying on its side wall a plurality of cutters 14 arranged in several rows.
  • the tool ends with a threaded portion 16 intended for connection with the rotation drive casing, not shown.
  • each cutter 14 is crimped into one end of a substantially cylindrical stud 18, the other end of which is itself crimped onto the body 12.
  • the cutter is in the form of a wafer circular comprising a first diamond-coated polycrystalline layer 22, which is bonded, by means of an appropriate binder, to a second layer 24 of tungsten carbide.
  • Each groove comprises two branches (only one being visible in FIG. 2) which descend from the cutting edge 14 into the stud, symmetrically with respect to the mediating plane of the cutting edge, and which meet at the back of the stud.
  • Each groove thus defines a preferential breaking surface of the cutter and the stud.
  • the weakening of the cutting edge is ensured by the choice of orientation, dimensions and positioning of the grooves. Breaking according to a given breaking surface occurs when the cutter has undergone a certain degree of wear and a predetermined load is applied to it.
  • FIG 2 there is shown a cutter fixed on stud free of any wear, and designated by 28 the rock formation to be drilled and by arrow f the direction of movement of the cutter. Initially, the upper face makes an acute angle fleeing ⁇ with the wall of the rock formation, so that only the cutter 14 attacks the rock. The efficiency of the cutting edge is then optimum.
  • FIG. 3 shows the cutter and the stud in a later state.
  • the entire upper part of the cutter and the stud has been worn by the rock. Contact with the rock formation is now made by the entire upper flat surface 30.
  • the cutting edge efficiency decreases. If a greater load is applied to maintain the same efficiency, the cutting edge and the stud are broken according to the surface containing the first groove 261.
  • the cutter then takes the sharpened shape shown in FIG. 4. Again, it has its maximum efficiency since it attacks the rock under the acute angle ⁇ which is clearly greater than the limit angle ⁇ indicated previously,
  • the number of grooves can be any. In FIG. 2, only five have been indicated, by way of nonlimiting example.
  • their spacing as well as their depth can also vary within wide limits, for example between 0.1 and 10 mm.
  • the grooves all have the same width and the same depth.
  • the grooves can define parallel planar surfaces, as in FIGS. 7 and 8 where, due to the perspective, only parallel rectilinear portions of grooves are seen.
  • the grooves 26c are formed in perspective by broken lines formed by "straight" sections.
  • the grooves 26d are curved so that successive breaks are made on concave surfaces.
  • the grooves can have their origin on the cutter 14 near the crystal diamond zone ( Figures 8, 10 and 11), on the stud 18 ( Figure 7), or alternatively on the cutter and on the support ( Figure 9 ).
  • the grooves may be discontinuous in the form of dots or lines.
  • the grooves can go all around the cutter and the stud or only a part only of the latter.

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Geology (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Earth Drilling (AREA)
  • Processing Of Stones Or Stones Resemblance Materials (AREA)
  • Drilling Tools (AREA)

Claims (9)

  1. Bohrwerkzeug (10) bestehend aus einem mit mehreren Tragteilen (18) versehenen Werkzeugkörper, auf denen jeweils eine selbstschärfende, plättchenförmige Schneide (14) angeordnet ist, die eine auf einer Wolframcarbidschicht (24) aufgebrachte polykristalline, diamantenbesetzte Außenschicht (22) aufweisen,
    dadurch gekennzeichnet,
    daß auf jeder Schneide (14) und/oder ihrem Tragteil (18) Zonen (26) geringerer Festigkeit eingerichtet sind, beispielsweise derart gestaltete Rillen oder Nuten, daß sie den Anstoß für nacheinanderfolgend zu bildender Bruchflächen geben können, die mit der zu durchbohrenden Felsformation (28) einen spitzen Schneidwinkel (α) bilden.
  2. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß der Schneidwinkel vorzugsweise im Bereich zwischen 25° und 55° enthaltene Werte aufweist.
  3. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß die Rillen oder Nuten parallel zueinander verlaufen.
  4. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß die Rillen oder Nuten jeweils die gleiche Breite und die gleiche Tiefe aufweisen.
  5. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß tiefe Rillen (26a) und weniger tiefe Rillen (26b) abwechselnd zueinander vorgesehen sind.
  6. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß jede Rille zwei Arme oder Abschnitte aufweist, die symmetrisch von der Schneide (14) aus symmetrisch bezüglich deren Mittelteilungsebene bis zum Tragteil (18) abwärts verlaufen und die sich am Rücken des Tragteils wiedervereinigen.
  7. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß die Rillen (26a) derart geradlinig verlaufen, daß sie ebene Bruchoberflächen bilden.
  8. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß die Rillen in Form gebrochener oder abgewinkelter Linien (26c) oder kurvenförmig verlaufen (26d) und konkave Bruchoberflächen bilden.
  9. Werkzeug nach Anspruch 1, dadurch gekennzeichnet, daß die Rillen diskontinuierlich beispielsweise in Form von Punkten oder Strichen vorgesehen sind.
EP91916192A 1990-09-14 1991-09-12 Selbstschärfendes schneidelement für bohrmeissel Expired - Lifetime EP0548163B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9011386A FR2666843B1 (fr) 1990-09-14 1990-09-14 Taillant d'outil de forage auto-affutable.
FR9011386 1990-09-14
PCT/FR1991/000720 WO1992005335A1 (fr) 1990-09-14 1991-09-12 Taillant d'outil de forage auto-affutable

Publications (2)

Publication Number Publication Date
EP0548163A1 EP0548163A1 (de) 1993-06-30
EP0548163B1 true EP0548163B1 (de) 1994-05-25

Family

ID=9400340

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91916192A Expired - Lifetime EP0548163B1 (de) 1990-09-14 1991-09-12 Selbstschärfendes schneidelement für bohrmeissel

Country Status (10)

Country Link
US (1) US5301762A (de)
EP (1) EP0548163B1 (de)
JP (1) JPH06500836A (de)
CA (1) CA2091676A1 (de)
DE (1) DE69102139T2 (de)
DK (1) DK0548163T3 (de)
ES (1) ES2053336T3 (de)
FR (1) FR2666843B1 (de)
NO (1) NO930907D0 (de)
WO (1) WO1992005335A1 (de)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5460233A (en) * 1993-03-30 1995-10-24 Baker Hughes Incorporated Diamond cutting structure for drilling hard subterranean formations
US5590729A (en) * 1993-12-09 1997-01-07 Baker Hughes Incorporated Superhard cutting structures for earth boring with enhanced stiffness and heat transfer capabilities
US5605198A (en) * 1993-12-09 1997-02-25 Baker Hughes Incorporated Stress related placement of engineered superabrasive cutting elements on rotary drag bits
US5435403A (en) * 1993-12-09 1995-07-25 Baker Hughes Incorporated Cutting elements with enhanced stiffness and arrangements thereof on earth boring drill bits
US5706906A (en) * 1996-02-15 1998-01-13 Baker Hughes Incorporated Superabrasive cutting element with enhanced durability and increased wear life, and apparatus so equipped
US5924501A (en) * 1996-02-15 1999-07-20 Baker Hughes Incorporated Predominantly diamond cutting structures for earth boring
US5967249A (en) * 1997-02-03 1999-10-19 Baker Hughes Incorporated Superabrasive cutters with structure aligned to loading and method of drilling
US5881830A (en) * 1997-02-14 1999-03-16 Baker Hughes Incorporated Superabrasive drill bit cutting element with buttress-supported planar chamfer
US6302224B1 (en) 1999-05-13 2001-10-16 Halliburton Energy Services, Inc. Drag-bit drilling with multi-axial tooth inserts
AU2004237810B2 (en) * 2003-12-16 2010-09-23 Voest-Alpine Bergtechnik Gesellschaft M.B.H. Roadheading or mining machine with roof bolt drilling and setting devices
US7373998B2 (en) * 2004-04-01 2008-05-20 Smith International, Inc. Cutting element with improved cutter to blade transition
US8936109B2 (en) 2010-06-24 2015-01-20 Baker Hughes Incorporated Cutting elements for cutting tools
WO2012012774A2 (en) 2010-07-23 2012-01-26 National Oilwell DHT, L.P. Polycrystalline diamond cutting element and method of using same
US8997900B2 (en) 2010-12-15 2015-04-07 National Oilwell DHT, L.P. In-situ boron doped PDC element
US20120199395A1 (en) * 2011-02-07 2012-08-09 Lynde Gerald D Cutting elements having a pre-formed fracture plane for use in cutting tools
US10352103B2 (en) * 2013-07-25 2019-07-16 Ulterra Drilling Technologies, L.P. Cutter support element
JP6468507B2 (ja) * 2013-11-28 2019-02-13 国立研究開発法人産業技術総合研究所 坑井掘削用ｐｄｃカッターおよび坑井掘削用ｐｄｃビット

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3882749A (en) * 1973-10-10 1975-05-13 James C Tourek Beavertooth cutting edge
US4227106A (en) * 1976-03-04 1980-10-07 Emerson Electric Co. High voltage induction motor without ladder insulation between motor windings and method of construction therefor
DE2719330C3 (de) * 1977-04-30 1984-01-05 Christensen, Inc., 84115 Salt Lake City, Utah Drehbohrmeißel
GB2055411B (en) * 1979-08-07 1983-01-12 Land & Marine Eng Ltd Cutting picks
US4277106A (en) * 1979-10-22 1981-07-07 Syndrill Carbide Diamond Company Self renewing working tip mining pick
US4324300A (en) * 1980-06-30 1982-04-13 Logan Jr Clifford K Rotary drill bit
US4629373A (en) * 1983-06-22 1986-12-16 Megadiamond Industries, Inc. Polycrystalline diamond body with enhanced surface irregularities
US4784023A (en) * 1985-12-05 1988-11-15 Diamant Boart-Stratabit (Usa) Inc. Cutting element having composite formed of cemented carbide substrate and diamond layer and method of making same
GB8626919D0 (en) * 1986-11-11 1986-12-10 Nl Petroleum Prod Rotary drill bits
GB2212190B (en) * 1987-11-12 1991-12-11 Reed Tool Co Improvements in cutting structures for rotary drill bits
US4869330A (en) * 1988-01-20 1989-09-26 Eastman Christensen Company Apparatus for establishing hydraulic flow regime in drill bits
DE3833767A1 (de) * 1988-10-05 1990-04-12 Hilti Ag Hohlbohrwerkzeug fuer gestein

Also Published As

Publication number Publication date
FR2666843B1 (fr) 1992-12-24
WO1992005335A1 (fr) 1992-04-02
DK0548163T3 (da) 1994-08-22
JPH06500836A (ja) 1994-01-27
DE69102139T2 (de) 1995-02-16
NO930907L (no) 1993-03-12
FR2666843A1 (fr) 1992-03-20
US5301762A (en) 1994-04-12
ES2053336T3 (es) 1994-07-16
EP0548163A1 (de) 1993-06-30
NO930907D0 (no) 1993-03-12
DE69102139D1 (de) 1994-06-30
CA2091676A1 (fr) 1992-03-15

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