EP0237359A2 - Fräsdrehbohrmeissel - Google Patents

Fräsdrehbohrmeissel Download PDF

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Publication number
EP0237359A2
EP0237359A2 EP87302180A EP87302180A EP0237359A2 EP 0237359 A2 EP0237359 A2 EP 0237359A2 EP 87302180 A EP87302180 A EP 87302180A EP 87302180 A EP87302180 A EP 87302180A EP 0237359 A2 EP0237359 A2 EP 0237359A2
Authority
EP
European Patent Office
Prior art keywords
face
cutting
cutter
rotary drag
bit according
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.)
Withdrawn
Application number
EP87302180A
Other languages
English (en)
French (fr)
Other versions
EP0237359A3 (de
Inventor
George Fyfe
Kenneth William Jones
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.)
Smith International Inc
Original Assignee
Smith International Inc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Smith International Inc filed Critical Smith International Inc
Publication of EP0237359A2 publication Critical patent/EP0237359A2/de
Publication of EP0237359A3 publication Critical patent/EP0237359A3/de
Withdrawn legal-status Critical Current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
    • E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
    • E21B10/50—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of roller type
    • 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
    • E21B10/50—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of roller type
    • E21B10/52—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of roller type with chisel- or button-type inserts
    • 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 rotary drag bits. More particularly, but not exclusively it relates to drag type rotary drill bits having cutters mounted to a cutting end of the drill bit, each of the cutters being rotatably secured to fixtures extending from the cutting end of the rotary drill bit.
  • Another object of this invention is to provide a means to prevent "balling" of the bit (build-up of debris adjacent the cutting face of the cutting segment).
  • a plurality of diamond inserts or natural diamond particles are embedded in the cutting face of a disc, the disc being rotatably secured within a saddle or support structure.
  • the cutter discs are caused to rotate due to the skewed angle of the saddle with respect to the radii from the axis of rotation of the drill string.
  • fluid nozzles are fixed in the bit body, fluid is directed toward the borehole bottom and, as the cutters rotate, the fluid washes and cools the synthetic or natural diamond segments or particles adjacent the bottom of borehole.
  • a cutting disc is rotated on a journal that is supported by a pair of journal blocks.
  • Such a structure provides for a larger diameter cutting disc causing slower rotation and consequent longer life.
  • This arrangement also permits selectability of the role of the cutter disc to provide for compressive or shear cutting forces on the formation.
  • Drag bit 11 is modified to accommodate the cutter elements of the present invention.
  • Drag bit 11 consists essentially of body 15 having a cutter face end 17 and a pin end 13.
  • the pin end 13 is the shank of the bit that connects to a drill string for rotation (not shown).
  • Figure 1 illustrates cutter face end 17 in an upward direction from the pin end 13, it will be understood by all those skilled in the art that the face end, when in the hole will be in a downward direction from pin end 13. The reader should bear this in mind as he follows through the descriptive portion of this patent specification.
  • cutter elements 19 Mounted on the cutter face 17 of rock bit 15 is a plurality of cutter elements, generally designated as 19, which generally lie on radial lines extending from the center of the face 17 of the drag bit 15.
  • Each of the cutter elements 19 are comprised of an insert base or saddle 21 and a cutter segment 22.
  • the insert base 21 is preferaby a tungsten carbide block having an aperture 24 therethrough ( Figure 3).
  • the base of the saddle 21 is preferably keyed with a slot 27 which fits into an aperture and mating key formed in the face 17 of the drill bit.
  • the saddle 21 may be press- or interference-fitted into an aperture formed in the face or may be fastened by brazing or some other convenient fastening means.
  • the cutter segment 22 is rotatably mounted within the aperture 24 of the saddle 21.
  • the structure of the cutter element 19 preferably comprises a support crank 25, which rotates within the journal aperture 24, bearing primarily against conical surface 24 ⁇ , formed on the end of the crank 25.
  • the end of the crank 25 supports cutter element 22 mounted thereon.
  • the crank 25 is contained within saddle block 21 by a keeper sleeve 23 tapered as shown in Figure 3.
  • the keeper is, for example, brazed on to the shaft of crank 25 to maintain the crank and cutter in place within the saddle.
  • the saddle 21 has an aperture 24 therethrough which is a journaled bearing for the crank 25.
  • the aperture 24 is tapered at both ends (12 and 14) in a manner which provides for both a rotary bearing and a thrust bearing surface.
  • Tapered end 14 may support, for example, a conically shaped bearing sleeve 30.
  • the sleeve may be fabricated from, for example, aluminium bronze, copper alloys or a spinodal alloy, all of which are suitable bearing materials.
  • bearing surfaces 12, 14 and 24 may be lined with a sleeve of bearing material as set forth above (not shown).
  • the cutter element 22 consists of a wafer of synthetic diamonds such as described in US Patent No. 4,253,533, for example. As shown in Figure 3, the cutting wafer 22 is at a negative rake angle "A" which is the result of the face 28 of saddle 21 being slanted as shown. This negative rate angle creates a compressive cutting force against the bottom 16 of the borehole which tends to crush more than slide away the earth formation.
  • each of the cutter elements 19 is mounted on face 17 of bit 11 along a radial line 32 ( Figure 4).
  • the vertical centre 20 of cutting face 22 intersects the circumferential movement arc 31 and the perpendicular plane 29.
  • the cutting face 22 does not lie on a plane that is parallel to the radius 32. It is, instead, skewed at an offset angle 33 from the radius 32.
  • This skew angle preferably is at a significant angle.
  • the amount of skew is chosen on the basis of the speed at which the cutting face is to rotate. The smaller the angle of skew, the slower the rotation of cutting element 22. Whether the cutting element 22 turns clockwise or counterclockwise is a matter of choice.
  • the important limit is that it is skewed from the radius of plane 32, causing forces to be exerted on the cutting element 22 as a result of the rotation of the drill face 17 which rotates the crank or body 25 of the cutter to rotate within the journal 24 in the saddle 21 ( Figure 3).
  • cutting element 22 is preferably synthetic diamond, cool and relatively clear of debris. Keeping this cutting element 22 cool prolongs the life of the cutting wafer a substantial amount, thereby creating a more effective drag bit with a considerably extended life span.
  • diamond subjected to extended periods of high heat concentration will cause the diamond to disintegrate thus continual movement minimizes heat concentration on the cutting edge of element 22.
  • a drag bit 35 is shown having a bit face 39 at the end opposite threaded pin end 37.
  • the cutting elements generally designated as 41, are as effective as the cutting elements 19 shown in Figure 1. They have cutting face 43 at one end of the journal, a saddle 42 and a keeper 45 at the other end of the journal. Each of the elements are mounted along a radial line which extends from the centre of the face 39 of the drag bit 35 (not shown).
  • the face 43 is not covered with a cutting material. Only the circumference of the face 43 has a cutting material 51 equidistantly spaced and inserted therein ( Figure 6).
  • a saddle 42 has a slanting face 47 with a journal 24 therethrough which is slanted (44 and 46) at the face and backsides to provide both thrust and rotary bearing surfaces.
  • the crank 49 is constructed differently than the crank 25 of Figure 3 in that it is composed of a series of parts.
  • the first part is a shaft 50 which provides a rotary bearing surface 26, preferably of tungsten carbide material which is cast at an end 48 of shaft 50 into cutting face 43, also preferably of tungsten carbide material.
  • the face 43 has attached around its perimeter a plurality of equidistantly spaced cutter segments 51 of polycrystalline diamond cutting elements, for example, which are fastened directly into the matrix of the cutting end 43.
  • the other end of the shaft 50 has brazed thereon a shaft keeper element 45.
  • the cutting element as shown in Figure 6, provides for compressive cutting forces primarily due to the negative rake angle as shown with respect to Figure 3.
  • FIGs 7 and 8 alternate configurations for the cutting face 43 are illustrated.
  • the particular structure for the individual cutting segments 51, mounted along the circumference of the cutting face 43 need not be cylindrical.
  • Figure 7 shows cylindrical inserts 51.
  • Figure 8 shows triangular prisms 52 inserted into the circumference of the cutting face 43.
  • Other shapes could also be used as desired.
  • these cutting segments are spaced so that the entire circumference of the cutting face is covered by the cutting segment material.
  • Drag bit 57 has a face 61 opposite to pin end 59.
  • Mounted on face 61 is a plurality of cutter elements 67 mounted for rotation about a shaft rotatively secured to journal blocks 63 and 65.
  • the cutting face 73 of the cutter 67 is oriented relative to a radius extending from the centre of the face 61 of the drag bit 57, as more clearly shown in Figure 10.
  • the desired skew angle of cutting face 73 on each of the cutters 67 is skewed in the same manner as the cutting face 22 of cutting element 19 ( Figure 4).
  • Figure 10 also illustrates fluid nozzles 77 located in the face 61 of drill bit 57 which causes drilling fluid to be washed across the cutting elements 73 to cool and clean them as they precess during operation of the bit in a borehole.
  • Figure 12 illustrates the cutting face 73 of the cutter 67 which has a plurality of circular shaped cylinders 75 embedded around its perimeter in the manner shown. End 74 of cylinders 75 serves as the cutting face for cutter 67.
  • the cutter 67 is mounted to a pair of bearing blocks 69 and 71 which provide both a thrust and a rotary bearing surface (not shown).
  • the cutter 67 rotates around the shaft which is held by bearing blocks 69 and 72.
  • the shaft may either be journalled into bearing block 69 and 71 or may be fixedly attached into bearing block 69 and 71 with the cutter elements 67 rotating around the fixed shaft. The latter arrangement is preferred.
  • the cutter 67 comes to an apex 78 which is on the plane passing through the geometric centre of the cutter 67.
  • the sloped surfaces 73 and 74 are part of a truncated conical section that slopes away from the apex 78.
  • One end 74 of the cylinder cutting members 75 are mounted into and exposed at the cuting face side 73 while a small portion of the side of the cylinders 75 are exposed at the opposite side 79. Rotation of the cutter 67 causes different cutting cylinders 75 to come into contact with the formation being gouged away as the drill bit head rotates.
  • the cutter 67 is preferably of tungsten carbide.
  • the cylindrical shaped cutter elements 75 are preferably of synthetic diamond which are held fast in the matrix of the tungsten carbide cutter structure 67.
  • the mounting or bearing block 69, 71 are also preferably of tungsten carbide or similar high strength material held fast to the face 61 of drill bit 57, either by press-fit or some other well known technique, such as brazing for example.
  • FIG 14. Another altnernate preferred embodiment of a cutter element according to the present invention is illustrated.
  • This embodiment is constructed to provide a positive rake angle "B" thereby providing true shear forces for slicing away the earth formation 88.
  • a pair of bearing blocks 85 and 83 are utilized and are fastened to the bit face 90.
  • Mounted for rotation with these bearing blocks is a truncated cone shaped cutter 92 having a cutting face 94 which is the base of the cone.
  • the sides of the cone 91 are sloped at an angle 93 that is less than ninety degrees.
  • the axis of rotation 89 of the cone cutter 92 is at an angle to the face 90 of the drill bit, creating a positive rake angle "B" with respect to the earth formation 88.
  • the cone cutter 92 rotates about the axis of rotation as explained above.
  • the journal blocks 85 and 83 are shaped to provide for both thrust and rotary bearing surfaces.
  • the cone cutter 92 is preferably constructed of a hard material such as tungsten carbide. In the alternative, cutter elements may be located along its circumference in the manner illustrated for the embodiments of Figures 7-13.
  • Drag bit 103 has a face 101 opposite pin end 105. Mounted on the face 101 is a plurality of disc-shaped cutters, generally designated as 107, each mounted to a pair of journal blocks 109 and 111. The orientation of the cutting faces 112 of cutter elements 113 of cutters 107 is the same as the orientation of the cutters shown in Figures 9, 10 and 11.
  • the cutter elements 113 mounted in the cylindrical cutter 115 is an arcuate segment that is, for example, three-quarters of an inch between radial sides 117 and 119.
  • the inlaid segments 113 are approximately five-eights of an inch thick.
  • the diameter of the cylinder 115 for this size of cutting segment is preferably four inches.
  • the material variations of the cutter elements 113, the cylindrical cutter 115 and the mounting blocks 109 and 111 are explained above.
  • the cutting face 113 of the disc-shaped cutter 107 is preferably mounted at a negative rake angle "C" of up to forty-five degrees from the perpendicular to the face 101 of the drag bit in certain situations.
  • FIG. 241 illustrates another embodiment for the cutter elements according to the present invention.
  • the cutting elements are effective in particularly hard formations.
  • This particular embodiment has a toroidally shaped cutting face 243 at one end of the journal generally designated as 249.
  • a saddle 242 is provided for journal 249 which provides a bearing surface 240 thereby.
  • a journal keeper 245 is provided at end 250 of journal 249.
  • cutter end 243 At the opposite end of journal 249 is cutter end 243, the peripheral edge of which is rounded or toroidally shaped at periphery 252.
  • the back side 260 of cutter end 243 is conically shaped and provides a bearing surface which mates against a complementary mating surface 244 in saddle 242.
  • Bearing sleeves may be provided as set forth relative to Figure 3.
  • the conical surfaces 260 and 244 serve to take the brunt of the thrust from the rotating cutter head 243 during operation of the cutter in a borehole.
  • Similar conically shaped bearing surface 246 formed in saddle 242 is provided having complementary surfaces on the keeper 245 which retains the rotating cutter within the saddle 242.
  • the rounded toroid surface 252 of cutter end 248 of the shaft 249 is covered with embedded natural or synthetic diamonds 251, the diamonds being mechanically fixed within a matrix of, for example, tungsten carbide applied to the end 248 of the shaft 249. This process is well known within the art.
  • the multiplicity of natural or synthetic diamonds 251 covering the rounded peripheral edge 252 are particularly effective in hard formations as previously indicated.
  • the cutter elements 241 are skewed from the radius of a plane as previously described which causes rotational forces to be exerted on the cutter elements 243.
  • Figure 19 illustrates the rear side of the cutter elements 241 showing the multiplicity of natural or synthetic diamonds 251 completely covering the rounded toroid surface 252 of end 243.
  • Figure 20 illustrates a front face view of the cutter element 241 showing the outer toroidally shaped surface 252 covered with natural diamonds 251.
  • the centre portion of the cutter end 243 is free of diamond cutter segments since it does not significantly contact any of the formation.
  • the end 240 of saddle 242 is preferably interference-fitted within a hold formed in the face of a drag bit as previously described (not shown).

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  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Earth Drilling (AREA)
  • Excavating Of Shafts Or Tunnels (AREA)
EP87302180A 1986-03-13 1987-03-13 Fräsdrehbohrmeissel Withdrawn EP0237359A3 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US83943486A 1986-03-13 1986-03-13
US839434 1997-04-10

Publications (2)

Publication Number Publication Date
EP0237359A2 true EP0237359A2 (de) 1987-09-16
EP0237359A3 EP0237359A3 (de) 1988-11-23

Family

ID=25279716

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87302180A Withdrawn EP0237359A3 (de) 1986-03-13 1987-03-13 Fräsdrehbohrmeissel

Country Status (6)

Country Link
EP (1) EP0237359A3 (de)
AU (1) AU590826B2 (de)
BR (1) BR8701601A (de)
CA (1) CA1260923A (de)
MX (1) MX161103A (de)
NO (1) NO871037L (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0347033A2 (de) * 1988-06-16 1989-12-20 Smith International, Inc. Bohrlochräumer
EP0370199A1 (de) * 1988-10-25 1990-05-30 General Electric Company Bohrmeissel mit polykristallinem Diamantsand
EP0569985A1 (de) * 1992-05-15 1993-11-18 Rainer Töpfer Rotationswerkzeug mit Hartmetalleinsätzen
WO1996012084A1 (en) * 1994-10-14 1996-04-25 Kennametal, Inc. Concave cutter bit
BE1012593A3 (fr) * 1995-11-13 2001-01-09 Baker Hughes Inc Couteaux et tuyeres a verrouillage mecanique.

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1533286A (en) * 1924-06-09 1925-04-14 Harry P Wickersham Well-drilling bit
US3830321A (en) * 1973-02-20 1974-08-20 Kennametal Inc Excavating tool and a bit for use therewith
US4253533A (en) * 1979-11-05 1981-03-03 Smith International, Inc. Variable wear pad for crossflow drag bit
EP0079243A1 (de) * 1981-11-09 1983-05-18 Sumitomo Electric Industries Limited Kompaktverbundkörper der einen Presskörper aus Diamant oder Bornitrid enthält
US4448269A (en) * 1981-10-27 1984-05-15 Hitachi Construction Machinery Co., Ltd. Cutter head for pit-boring machine
US4553615A (en) * 1982-02-20 1985-11-19 Nl Industries, Inc. Rotary drilling bits
GB2167107A (en) * 1984-11-15 1986-05-21 Keith Malcolm Brown Drilling bits

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1584752A (en) * 1977-05-25 1981-02-18 Transport Secretary Of State F Rock cutting tools

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1533286A (en) * 1924-06-09 1925-04-14 Harry P Wickersham Well-drilling bit
US3830321A (en) * 1973-02-20 1974-08-20 Kennametal Inc Excavating tool and a bit for use therewith
US4253533A (en) * 1979-11-05 1981-03-03 Smith International, Inc. Variable wear pad for crossflow drag bit
US4448269A (en) * 1981-10-27 1984-05-15 Hitachi Construction Machinery Co., Ltd. Cutter head for pit-boring machine
EP0079243A1 (de) * 1981-11-09 1983-05-18 Sumitomo Electric Industries Limited Kompaktverbundkörper der einen Presskörper aus Diamant oder Bornitrid enthält
US4553615A (en) * 1982-02-20 1985-11-19 Nl Industries, Inc. Rotary drilling bits
GB2167107A (en) * 1984-11-15 1986-05-21 Keith Malcolm Brown Drilling bits

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0347033A2 (de) * 1988-06-16 1989-12-20 Smith International, Inc. Bohrlochräumer
EP0347033A3 (de) * 1988-06-16 1991-03-20 Smith International, Inc. Bohrlochräumer
EP0370199A1 (de) * 1988-10-25 1990-05-30 General Electric Company Bohrmeissel mit polykristallinem Diamantsand
EP0569985A1 (de) * 1992-05-15 1993-11-18 Rainer Töpfer Rotationswerkzeug mit Hartmetalleinsätzen
WO1996012084A1 (en) * 1994-10-14 1996-04-25 Kennametal, Inc. Concave cutter bit
BE1012593A3 (fr) * 1995-11-13 2001-01-09 Baker Hughes Inc Couteaux et tuyeres a verrouillage mecanique.

Also Published As

Publication number Publication date
AU6998587A (en) 1987-09-17
CA1260923A (en) 1989-09-26
AU590826B2 (en) 1989-11-16
NO871037L (no) 1987-09-14
BR8701601A (pt) 1988-01-12
NO871037D0 (no) 1987-03-13
EP0237359A3 (de) 1988-11-23
MX161103A (es) 1990-07-31

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Inventor name: JONES, KENNETH WILLIAM