EP0119620A2 - Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen - Google Patents

Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen Download PDF

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Publication number
EP0119620A2
EP0119620A2 EP84102985A EP84102985A EP0119620A2 EP 0119620 A2 EP0119620 A2 EP 0119620A2 EP 84102985 A EP84102985 A EP 84102985A EP 84102985 A EP84102985 A EP 84102985A EP 0119620 A2 EP0119620 A2 EP 0119620A2
Authority
EP
European Patent Office
Prior art keywords
cutting element
bit
diamond cutting
improvement
teeth
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.)
Granted
Application number
EP84102985A
Other languages
English (en)
French (fr)
Other versions
EP0119620A3 (en
EP0119620B1 (de
Inventor
Alexander K. Meskin
Clifford R. Pay
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.)
Baker Hughes Oilfield Operations LLC
Original Assignee
Christensen Inc
Norton Christensen Inc
Eastman Christensen Co
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 Christensen Inc, Norton Christensen Inc, Eastman Christensen Co filed Critical Christensen Inc
Publication of EP0119620A2 publication Critical patent/EP0119620A2/de
Publication of EP0119620A3 publication Critical patent/EP0119620A3/en
Application granted granted Critical
Publication of EP0119620B1 publication Critical patent/EP0119620B1/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

Definitions

  • the present invention relates to the field of earth boring tools and in particular to rotating bits incorporating diamond elements.
  • the PCD products are fabricated from synthetic and/or appropriately sized natural diamond crystals under heat and pressure and in the presence of a solvent/catalyst to form the polycrystalline structure.
  • the polycrystalline structures includes sintering aid material distributed essentially in the interstices where adjacent crystals have not bonded together.
  • the resulting diamond sintered product is porous, porosity being achieved by dissolving out the nondiamond material or at least a portion thereof, as disclosed for example, in U. S. 3,745,623; 4,104,344 and 4,224,380.
  • a material may b ⁇ described as a porous PCD, as referenced in U.S. 4,224,380.
  • Polycrystalline diamonds have been used in drilling products either as individual compact elements or as relatively thin PCD tables supported on a cemented tungsten carbide (WC) support backings.
  • the PCD compact is supported on a cylindrical slug about 13.3 mm in diameter and about 3 mm long, with a PCD table of about 0.5 to 0.6 mm in cross section on the face of the cutter.
  • a stud cutter the PCD table also is supported by a cylindrical substrate of tungsten carbide of about 3 mm by 13.3 mm in diameter by 26mm in overall length.
  • These cylindrical PCD table faced cutters have been used in drilling products intended to be used in soft to medium-hard formations.
  • the natural diamond could be either surface-set in a predetermined orientation, or impregnated, i.e., diamond is distributed throughout the matrix in grit or fine particle form.
  • porous PCD compacts and those said to be temperature stable up to about 1200°C are available in a variety of shapes, e.g., cylindrical and triangular.
  • the triangular material typically is about 0.3 carats in weight, measures 4mm on a side and is about 2.6mm thick. It is suggested by the prior art that the triangular porous PCD compact be surface-set on the face with a minimal point exposure, i.e., less than 0.5mm above the adjacent metal matrix face for rock drills.
  • the difficulties with such placements are several.
  • the difficulties may be understood by considering the dynamics of the drilling operation.
  • a fluid such as water, air or drilling mud is pumped through the center of the tool, radially outwardly across the tool face, radially around the outer surface (gage) and then back up the bore.
  • the drilling fluid clears the tool face of cuttings and to some extent cools the cutter face.
  • the cuttings may not be cleared from the face, especially where the formation is soft or brittle.
  • the clearance between the cutting surface-formation interface and the tool body face is relatively small and if no provision is made for chip clearance, there may be bit clearing problems.
  • the weight on the drill bit normally the weight of the drill string and principally the weight of the drill collar, and the effect of th 4 fluid which tends to lift the bit off the bottom. It has been reported, for example, that the pressure beneath a diamond bit may be as much as 1000 psi greater than the pressure above the bit, resulting in a hydraulic lift, and in some cases the hydraulic lift force exceeds 50% of the applied load while drilling.
  • Run-in in diamond bits is required to break off the tip or point of the triangular cutter before efficient cutting can begin.
  • the amount of tip loss is approximately equal to the total exposure of natural diamonds. Therefore, an extremely large initial exposure is required for synthetic diamonds as compared to natural diamonds. Therefore, to accommodate expected wearing during drilling, to allow for tip removal during run-in, and to provide flow clearance necessary, substantial initial clearance is needed.
  • Still another advantage is the provision of a drilling tool in which thermally stable PCD elements of a defined predetermined geometry are so positioned and supported in a metal matrix as to be effectively locked into the matrix in order to provide reasonably long life of the tooling by preventing loss of PCD elements other than by normal wear.
  • the present invention is an improvement in a rotating bit having a bit face wherein the improvement comprises a plurality of teeth disposed on the bit and wherein each tooth includes a diamond cutting element.
  • the diamond cutting element is particularly characterized by having the shape of a segment of a cylinder.
  • the segment includes at least one planar surface and the planar surface forms, at least in part, a leading surface of the tooth.
  • the cylindrical segment is a split half cylinder or a split quarter cylinder.
  • the diamond cutting element is characterized by having a longitudinal axis lying along the length of the cylinder and wherein the cylindrical shape is a half cylinder shape, the planar surface is a planar surface lying along a diameter of the cylindrical shape.
  • the cylindrical segment is a quarter segment of a full cylinder
  • the quarter segment includes an apical edge which lies along the longitudinal axis of the cylinder.
  • the apical edge of the quarter cylinder and the planar surface of the half cylinder diamond cutting element serves as an exposed leading surface of the tooth and is disposed adjacent to a fluid channel thereby forming in whole or in part one edge or wall of the fluid channel.
  • the present invention is an improvement in a tooth design used in rotating bits, particularly rotary bits, wherein the tooth includes a diamond cutting element and in particular a diamond cutting element derived from cylindrical polycrystalline synthetic diamond (PCD).
  • PCD cylindrical polycrystalline synthetic diamond
  • full cylindrical elements are generally commercially available but not in segment form.
  • Such synthetic diamond is formed in the shape of a full circular cylinder having one planar end perpendicular to the longitudinal axis of the cylindrical shape and an opposing domed end, generally formed in the shape of a circular cone.
  • Such elements are typically available in a variety of sizes with the above described shape.
  • the full cylindrical diamond element is segmented to form a cylindrical segment wherein the segment is then axially disposed within a bit tooth.
  • segmented or split cylindrical elements thus provide a cutting element with improved cutting efficiency with less use o diamond material and less tendency to dull or polish.
  • Figure 1 is a cross-sectional view of a first embodimen of the present invention showing a tooth, generally denoted by reference numeral 10, incorporating a diamond cutting element, generally denoted by reference numeral 12.
  • Element 12 is axiall disposed within the tungsten-carbide matrix material 14 of the rotating bit.
  • longitudinal axis 16 of element 1 is orientedT to be approximately perpendicular to bit surface 18 at the location of tooth 10.
  • Bit surface 18 may be bit face of crown of a rotating bit or may be the superior surface of a raised land or pad disposed upon a bit crown. In either case, bit surface 18 is taken in the present description as the basal surface upon which tooth 10 is disposed.
  • element 12 is approximately a quarter section or 90 degrees of the full cylindrical shape of the PCD element normally available.
  • Element 12 is cut using a conventional laser cutter. For example, deep cuts are made every 90 degrees parallel to the longitudinal axis 16 of a full cylindrical diamond element.
  • the laser could be used t completely cut through the diamond element, it has been found possible that with deep scoring, the diamond can then be fractured with propagation of the fracture lying approximately along the continuation of the plane of the laser cut.
  • the laser may cut a millimeter or less into and along the length of the full cylindrical diamond element.
  • a diametrically opposed cut of equal depth is also provided on the cylinder. Thereafter, the cylinder may be split in half and then later quartered on another laser cut by fracturing the diamond element using an impulsive force and chisel.
  • Diamond element 12 is disposed within tooth 10 as isshown in Figure 2 so that the apical edge 20 of diamond 12 formed by the cleavage planes or laser cuts which have formed radial surfaces 22, is oriented in the leading or forward direction of tooth 10 as defined by the rotation of the bit upon which tooth 10 is disposed.
  • a portion of element 12 is fully exposed above bit surface 18 and in particular, that apical edge 20 forms the foremost portion of diamond element 12 as the tooth moves forwardly in the plane of the figure.
  • Surfaces 22 define a dihedral angle and the tangential direction of movement of tooth 10 during normal cutting operation is generally along the direction of the bisector of the dihedral angle.
  • a channel 24 is defined immediately in front of apical edge 20 to serve as a waterway or collector as appropriate.
  • leading surfaces 22 and edge 20 can be placed virtually in channel 24 or immediately next thereto, forming as shown in Figure 1, one wall of channel 24 or a portion thereof, whereby hydraulic fluid supplied to and flowing through channel 24 during normal drilling operations will serve to cool and clean the cutting face of tooth 10 and in particular the leading edge and surfaces of diamond element 12.
  • tooth 10 is shown as having a trailing support 26 of matrix material integrally formed with matrix material 14 of the bit and extending above bit surface 18 to the trailing surface of diamond element 12.
  • the slope of trailing support 26 is chosen so as to substantially match the slope of the top conical surface 28 of element 12 with the opposing end of element 12, which is a right circular plane, being embedded within matrix material 14.
  • the exact shape and placement of trailing support 26 can be varied without departing from the spirit and scope of the present invention.
  • trailing support 26 may be even more substantial than that shown in- Figure 1 and may assume a slope different from surface 28 of element 12 to thereby provide additional matrix reinforcing material behind and on top of conical surface 28 and leading surfaces 22.
  • Figure 2 illustrates in plan view the tooth of Figure 1 in a double row or triad configuration.
  • a first row of teeth including teeth 10a and 10b is succeeded by a trailing tooth or second row of teeth including tooth 10c, wherein tooth 10c is placed halfway between the spacing of teeth 10a and 10b. Therefore, it can be appreciated that as the teeth 10a-c move forward during cutting of a rock formation, the diamond cutting elements incorporated within each of the teeth effectively overlap and provide a uniform annular swath cut into the rock formation as the bit rotates.
  • Figure 4 which shows in plan view a coring bit incorporating the teeth of Figures 1 and 2 illustrates the disposition of such a double row of configured teeth, collectively denoted by reference numeral 32, on pad 30.
  • Bit 34 also includes an inner gage 44 wherein the inner and outer gage are connected by waterways 31.
  • Each pad 30 begins at or near inner gage 44 and is disposed across the bit face in a generally radial direction as seen in Figure 4 and splits into two pads which then extend to outer gage 36.
  • the bifurcated pads are separated by a collector 33 which communicates with a gage collector 35 or junk slot 37 as may be appropriate.
  • a gage collector 35 or junk slot 37 as may be appropriate.
  • other types of coring bits and petroleum bits could have been illustrated to show the use of the teeth of Figures 1-3 other than the particular bit illustrated in Figure 4. Therefore, the invention is not to be limited to any particular bit style or in fact, even to rotating bits.
  • FIG. 3 a cross-sectional view of the shoulder-to-gage transition utilizing the teeth of Figures 1 and 2 is illustrated.
  • the bit generally denoted by reference numeral 34, is characterized by having a vertical cylindrical section or gage 36 which serves to define and maintain the diameter of the bore drilled by bit 34. Below gage 36, bit 34 will slope inwardly along a designed curve toward the center of the bit.
  • a half profile is shown in Figure 5 and is a simple elliptical cross section characterized by an outer shoulder 38, nose 40 and inner shoulder 42. Inner diameter of the core is then defined by inner gage 44.
  • outer gage 36 is shown as incorporating a half cylindrical segment 46, which is surface set and embedded into gage 36 so that the rounded cylindrical surface 48 is exposed above bit surface 50 of gage 36 with the flat longitudinal face 52 of the half cylindrical segment embedded within matrix material 54 of bit 34.
  • Half cylindrical diamond crystalline element 46 is more clearly depicted in cross-sectional view in Figure 4 on gage 36.
  • teeth 32 as shown in Figure 4 include quarter cylindrical segments, shown in rear view in Figure 3 as exemplified by diamond elements 56 and 58.
  • Each element 56 is disposed within bit 34 so as to extend therefrom in a perpendicular direction as defined by the normal to bit surface at each point where such element is located.
  • each element 56 and 58 is exposed by a uniform amount, namely, 2.7 mm (0.105") above the bit face.
  • Element 56 which is the diamond element closest to gage 36 is placed upon shoulder 38 at such a position next to the beginning of gage 36 so that its outermost radially extending point, namely, apex 60, extends radially from the longitudinal axis of rotation of bit 34 by an amount equal to the radial distance from the longitudinal axis of bit 34 by the gage diamonds, in particular diamond 46.
  • gage diamond 46 extends above bit surface 50 by 0.64 mm (0.025").
  • gage diamonds 46a are disposed at and slightly below gage level 62 on ⁇ type I gage column corresponding to a type I pad 30 shown in plai view in Figure 4.
  • Gage diamonds 46b are thus placed adjacent to a pad of type II and gage diamonds 46c placed on a gage section correspondingg to a type III pad.
  • Gage diamonds 46a-c thus form a staggered pattern as best illustrated in Figure 6 which effectively presents a high cutting element density as the bit rotates.
  • Above gage diamonds 46a-46b are conventional natural diamonds surface set in broaches, namely, kickers which are typical of the order of 6 per carat in size.
  • the adjacent row of teeth on the next adjacent gage section begins at a quarter spacing displaced from the corresponding row of gage diamonds on the adjacent pad.
  • type I pad corresponds to gage diamonds 46a having two rows with each row offset by half a space between each other
  • pad II corresponds to gage diamonds 46b which are similarly offset with respect to each other and are spaced down the gage one quarter of a spacing as compared to gage diamonds 46a on pad type I.
  • a tooth generally denoted by reference numeral 66, incorporates a half cylindrical segment diamond element 68 extending from and embedded in matrix material 14 in much the same manner as illustrated in connection with the first embodiment of Figures 1 and 2.
  • PCD element 68 is- characterized by a half cylindrical surface 70 and a planar leading surface 72, which is formed as described above by cleaving a full cylinder along the diameter.
  • diamond element 68 also includes a conical or domed upper surface 74 forming the apical point 76 of element 68.
  • a trailing support 78 of integrally formed matrix material is smoothly fared from surface 74 to bit face 18 to provide tangential reinforcement and support for diamond element 68 against the cutting forces to which element 68 is subjected.
  • trailing supports 78 are tapered to a point 80 on bit face 18 thereby forming a teardrop shaped plan outline for tooth 66.
  • diamond element 68 is placed immediately adjacent to and forms one side of a channel 80 formed into matrix material 14 which channel 80 serves as a conventional waterway or collector as may be appropriate with the same advantages-as described in connection with the first embodiment of Figure 1.
  • the second embodiment of Figure 8 similarly consists of two rows of teeth 66a and 66b followed by a second row represented by tooth 66c. Tooth 66c is located halfway between the spacing between tooth 66a and 66b as defined with respect to the direction of tangential movement during normal drilling operations.
  • the double row of teeth are disposed on a petroleum or coring bit in the same manner as illustrated in connection with the first embodiment of the invention in Figure 4. Teeth 66 are thus disposed within matrix material 14 and used on a bit in the same
  • teeth 66 as shown in Figure 8 clearly provide a broader cutting surface and a diamond element 68 containing twice the diamond material and structural bulk as compared to diamond elements 12 of the first embodiment. Therefore, in those applications where a larger cutting bite is required or where greater structural strength is needed in the diamond element, the half cylindrical split elements 68 of the second embodiment may be more advantageously used than the quarter split diamond elements of the first embodiment.
  • split cylindrical segment has been shown as perpendicularly embedded into the matrix material, it is clearly contemplated that it may be either forwardly or rearwardly raked if required by design objectives. Therefore, the illustrated embodiment must be understood as presented only as an example of the invention and should not be taken as limiting the invention as set forth in the following claim.

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  • 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)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
EP84102985A 1983-03-21 1984-03-19 Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen Expired - Lifetime EP0119620B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US47706883A 1983-03-21 1983-03-21
US477068 1983-03-21

Publications (3)

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EP0119620A2 true EP0119620A2 (de) 1984-09-26
EP0119620A3 EP0119620A3 (en) 1986-02-12
EP0119620B1 EP0119620B1 (de) 1990-02-28

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EP84102985A Expired - Lifetime EP0119620B1 (de) 1983-03-21 1984-03-19 Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen

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EP (1) EP0119620B1 (de)
JP (1) JPS6016692A (de)
AU (1) AU2568884A (de)
BR (1) BR8401280A (de)
CA (1) CA1218355A (de)
DE (1) DE3481435D1 (de)
ZA (1) ZA842109B (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0189212A1 (de) * 1985-01-25 1986-07-30 Eastman Christensen Company Kerbender Schneidmeissel
EP0285678A1 (de) * 1985-08-02 1988-10-12 Eastman Teleco Company Bohrmeissel für weiche bis harte Formationen
US4926950A (en) * 1986-03-27 1990-05-22 Shell Oil Company Method for monitoring the wear of a rotary type drill bit

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009030052A1 (en) 2007-09-05 2009-03-12 Groupe Fordia Inc. Drill bit

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5382601A (en) * 1976-12-28 1978-07-21 Tokiwa Kogyo Kk Rotary grinding type excavation drill head
US4351401A (en) * 1978-06-08 1982-09-28 Christensen, Inc. Earth-boring drill bits
US4373593A (en) * 1979-03-16 1983-02-15 Christensen, Inc. Drill bit
DE3114749C2 (de) * 1981-04-11 1983-10-27 Christensen, Inc., 84115 Salt Lake City, Utah Keilförmiges Schneidglied für Drehbohrmeißel zum Tiefbohren
US4529047A (en) * 1983-02-24 1985-07-16 Norton Christensen, Inc. Cutting tooth and a rotating bit having a fully exposed polycrystalline diamond element

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0189212A1 (de) * 1985-01-25 1986-07-30 Eastman Christensen Company Kerbender Schneidmeissel
EP0285678A1 (de) * 1985-08-02 1988-10-12 Eastman Teleco Company Bohrmeissel für weiche bis harte Formationen
US4926950A (en) * 1986-03-27 1990-05-22 Shell Oil Company Method for monitoring the wear of a rotary type drill bit

Also Published As

Publication number Publication date
CA1218355A (en) 1987-02-24
EP0119620A3 (en) 1986-02-12
JPS6016692A (ja) 1985-01-28
EP0119620B1 (de) 1990-02-28
BR8401280A (pt) 1984-10-30
DE3481435D1 (de) 1990-04-05
AU2568884A (en) 1984-09-27
ZA842109B (en) 1984-11-28

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