EP0119620B1 - Type de dent comportant l'utilisation d'éléments de coupe diamantés cylindriques - Google Patents

Type de dent comportant l'utilisation d'éléments de coupe diamantés cylindriques Download PDF

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Publication number
EP0119620B1
EP0119620B1 EP84102985A EP84102985A EP0119620B1 EP 0119620 B1 EP0119620 B1 EP 0119620B1 EP 84102985 A EP84102985 A EP 84102985A EP 84102985 A EP84102985 A EP 84102985A EP 0119620 B1 EP0119620 B1 EP 0119620B1
Authority
EP
European Patent Office
Prior art keywords
bit
cutting element
teeth
gage
row
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
EP84102985A
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German (de)
English (en)
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EP0119620A2 (fr
EP0119620A3 (en
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
Eastman Christensen Co
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Filing date
Publication date
Application filed by Eastman Christensen Co filed Critical Eastman Christensen Co
Publication of EP0119620A2 publication Critical patent/EP0119620A2/fr
Publication of EP0119620A3 publication Critical patent/EP0119620A3/en
Application granted granted Critical
Publication of EP0119620B1 publication Critical patent/EP0119620B1/fr
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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 a rotatable bit for use in earth boring as claimed in the pre- charactering portion of claim 1.
  • a rotatable bit of the kind referred to (US-A-4 373 593) comprises cutting member connected to a bit body by soldering or adhesion without any embedding into the the matrix material of bit body.
  • Each of the cutting members consist of a supporting portion and a cutting portion disposed on the supporting portion.
  • Each cutting member being formed as a wedge shaped cut-out segment of sintered body with a supporting portion surrounding the cutting portion as a casing at least at the periphery, said cutting portion being a material selected from compacted diamond and compacted cubic boron nitride.
  • EP-A-0 117 506 fifed priortothefiHng date of the present invention discloses a bit comprising a matrix body member including a plurality of spaced synthetic polycrystalline diamond cutting elements mounted directly in the matrix during matrix formation, said matrix material forming a plurality of spaced teeth, and at least some of said teeth including a trailing support contacting the rear of the associated cutting element.
  • Object of the invention is to provide a rotatable drill bit of the kind referred to in the pre-characterising portion of claim 1, which can be manufactured at reasonable costs, and will perform well in terms of length of bit life and rate of penetration.
  • the present invention is an improvement in a rotatable bit as claimed in claim 1, and further embodiments of the bit according to the invention being claimed in claims 2-12.
  • the present invention affixes thermally-stable cutting elements securely in a protected manner in the bit in a one-step process, providing accurate orientation without any laborious post-furnacing cutter affixation.
  • the present invention also provides improved cutting efficiency with less use of diamond material, improved cleaning and cooling efficiency and less tendency to dull or to polish.
  • 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 is 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 of diamond material and less tendency to dull or polish.
  • Figure 1 is a cross-sectional view of a first embodiment 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 axially disposed within the tungsten- carbide matrix material 14 of the rotating bit.
  • longitudinal axis 16 of element 12 is oriented to be approximately perpendicular to bit surface 18 atthe location of tooth 10.
  • Bit surface 18 may be bit face of a 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, but 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 to 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. Therafter, 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 is shown 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 surfaces 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: For example, with larger diameter elements 12, cut from larger diameter synthetic cylinders, no trailing support 26 may be provided at all and element 12 may be totally free standing above bit surface 18 like an embedded stud. In the cases of thinner cylindrical elements 12, 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 a 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 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 prependicular 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 a type I gage column corresponding to a type I pad 30 shown in plan 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 corresponding 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 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 1.
  • 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 cellector 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 as defined with respect of 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 manner as are teeth 10 of Figures 1 and 2.
  • 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.

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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)

Claims (12)

1. Trépan rotatif (34) comportant une face de trépan (18) et une pluralité de dents (10, 66) disposée sur cette face de trépan et comprenant chacune un élément de coupe en diamant poly- cristallin (12, 68), l'élément de coupe (12, 68) ayant la forme d'un segment de cylindre, le segment de forme cylindrique de l'élément de coupe (12,68) présentant au moins une face plane (22, 72), la face plane de l'élément de coupe étant orientée dans la dent (10,66) de manière à former au moins en partie une face antérieure de la dent (10, 66) définie par la direction de mouvement de la dent (10, 66) pendant une opération de forage normale lorsque le trépan (34) tourne, caractérisé en ce qu'une extrémité de la forme cylindrique est façonnée en un segment conique, chaque élément de coupe (12, 68) étant monté directement dans la matrice du trépan (34) pendant la formation de cette matrice, et un support traînant (26, 78) étant prévu d'une seule pièce avec la face de trépan (18) et s'etendant en pente à partir de la face de trépan (18) jusqu'à une face traînante (28, 74) de l'élement de coupe (12, 68), la pente du segment conique correspondant approximativement à celle du support traînant (26, 78).
2. Trépan rotatif suivant la revendication 1, dans lequel le segment de l'élément de coupe de forme cylindrique est un segment semi-cylindrique (68), définissant ainsi une face antérieure plane (72) disposée suivant un diamètre de la forme cylindrique.
3. Trépan rotatif suivant la revendication 1, dans lequel le segment de l'élément de coupe de forme cylindrique est un segment en forme de quartier, définissant ainsi une arête (20) et deux faces antérieures (22) formant un angle dièdre derrière l'arêtel, l'angle dièdre étant d'environ 90°.
4. Trépan rotatif suivant la revendication 3, dans lequel l'élément de coupe de.forme cylindrique présente un axe longitudinal (16) situé le long de l'arête (20) et dans lequel l'élément de coupe (12) est orineté par rapport à la face de trépan (18), de telle sorte que l'axe longitudinale (16) y soit approximativement perpendiculaire.
5. Trépan rotatif suivant la revendication 3 ou 4, dans lequel un canal (24) est ménagé dans la face de trépan (18) immédiatement en avant de l'élément de coupe en diamant (12, 68) et dans lequel l'arête (20) est disposée sur le canal à fluide (24) et forme au moins une partie d'une paroi adjacente de ce canal.
6. Trépan rotatif suivant l'une quelconque des revendications 1 à 5, dans lequel une pluralité de rangées des dents (12, 68) est disposée sur le trépan (34) et dans lequel les rangées sont appariées pour former une première et une seconde rangée associées, l'espacement entre les dents (10a, 10b, 10c) dans la première et la deuxième rangée étant en substance constant, les dents (10c) de la seconde rangée étant disposées der- mière les dents (10a, 10b) de la première rangée par rapport au mouvement tangentiel des dents pendant la rotation du trépan (34) durant des opérations de forage normales, les dents (10c) de la seconde rangée étant facilement disposées au milieu entre les dents (10a, 10b) de la première rangée, de sote que les dents (10a, 10b, 10c) de la première et de la seconde rangée taillent, lorsque le trépan (34) tourne, une bande annulaire uniforme d'une densité de dents effective supérieure à celle qui peut être obtenue par la densité des dents dans la première ou la seconde rangée seule, les dents (10c) de la seconde rangée suivant les dents (10a, 10b) de la première rangée dans les interstices séparant les dents (10a, 10b) de la première rangée et derrière ceux- ci.
7. Trépan rotatif suivant la revendication 1, dans lequel le trépan (34) comprend une partie de calibrage (36) et un épaulement incliné (38), les dents (56, 58) étant disposées sur l'épaulement (38) près de la partie de calibrage (36) et s'étendant au-dessus de la face de trépan (18) d'une première distance prédéterminée, la partie de calibrage (36) comprenant des éléments de coupe disposés au-dessus de la face de trépan (18) de la partie de calibrage (36) d'une seconde distance prédéterminée, et le trépan (34) présentant, en outre, un axe de rotation longitudinal, la distance radiale séparant cet axe de rotation longitudinal des éléments de coupe (46) disposés et s'étendant au-dessus de la partie de calibrage (36) étant approximativement égale à la distance radiale séparant ledit axe de rotation longitudinal d'un élément supérieur (56) parmi les éléments de coupe en diamant (56, 58) disposés sur l'épaulement (38), l'élément de coupe supérieur (56) sur l'épaulement (38) étant positionné sur cet épaulement (38) à proximité de la partie de calibrage (36) à un endroit tel que les distances radiales séparant l'axe de rotation longitudinal des éléments de coupe (46) sur la partie de calibrage (36) et de l'élément de coupe supérieur (56) sont réglées approximativement égales.
8. Trépan rotatif suivant l'une quelconque des revendications 1 à 7, dans lequel la forme cylindrique de l'élément de coupe est celle d'un cylindre circulaire.
9. Trépan rotatif suivant l'une quelconque des revendications 3 à 6, dans lequel le segment d'élément de coupe de forme cylindrique est un segment en forme de quartier (12) d'un cylindre complet et dans lequel l'arête (20) est disposée le long de l'axe longitudinal (16).
10. Trépan rotatif suivant la revendication 1 ou 9, dans lequel l'élément de coupe (12) est disposé dans chaque dent (10), de telle sorte que chaque arête (20) forme la partie antérieure de l'élément de coupe (12).
11. Trépan rotatif suivant la revendication 10, dans lequel la direction de mouvement tangentiel de la dent (10) est disposée approximativement le long de la bissectrice de l'angle dièdre définissant l'arête (20).
12. Trépan rotatif suivant la revendication 1 ou '2, dans lequel l'élément de coupe (12) forme une paroi d'un canal de fluide adjacent (24) défini dans la face de trépan (18), devant la dent (10).
EP84102985A 1983-03-21 1984-03-19 Type de dent comportant l'utilisation d'éléments de coupe diamantés cylindriques Expired - Lifetime EP0119620B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US477068 1974-06-05
US47706883A 1983-03-21 1983-03-21

Publications (3)

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

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EP84102985A Expired - Lifetime EP0119620B1 (fr) 1983-03-21 1984-03-19 Type de dent comportant l'utilisation d'éléments de coupe diamantés cylindriques

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

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8485283B2 (en) 2007-09-05 2013-07-16 Groupe Fordia Inc. Drill bit

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN86100885A (zh) * 1985-01-25 1986-08-20 诺顿-克里斯坦森公司 一种改进的沟槽切削型钻头
US4673044A (en) * 1985-08-02 1987-06-16 Eastman Christensen Co. Earth boring bit for soft to hard formations
GB2188354B (en) * 1986-03-27 1989-11-22 Shell Int Research Rotary drill bit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0117506A2 (fr) * 1983-02-24 1984-09-05 Eastman Christensen Company Dent de coupe et trépan rotatif avec un élément diamanté polycristallin totalement exposé

Family Cites Families (4)

* 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

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0117506A2 (fr) * 1983-02-24 1984-09-05 Eastman Christensen Company Dent de coupe et trépan rotatif avec un élément diamanté polycristallin totalement exposé

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8485283B2 (en) 2007-09-05 2013-07-16 Groupe Fordia Inc. Drill bit

Also Published As

Publication number Publication date
AU2568884A (en) 1984-09-27
JPS6016692A (ja) 1985-01-28
BR8401280A (pt) 1984-10-30
DE3481435D1 (de) 1990-04-05
EP0119620A2 (fr) 1984-09-26
EP0119620A3 (en) 1986-02-12
CA1218355A (fr) 1987-02-24
ZA842109B (en) 1984-11-28

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