EP0119620B1 - Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen - Google Patents

Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen Download PDF

Info

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
Other languages
English (en)
French (fr)
Other versions
EP0119620A3 (en
EP0119620A2 (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
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 Eastman Christensen Co filed Critical Eastman Christensen Co
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

Links

Images

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.

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)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)

Claims (12)

1. Drehbohrmeißel (34) mit einer Meißeloberfläche (18) und einer Mehrzahl von auf dieser angeordneten Zähnen (10; 66), von denen jeder ein polykristallines Diamantschneidelement (12; 68) umfaßt, das die Form eines Segmentes eines Zylinders aufweist, wobei das Segment der Zylinderform des Schneidelements (12; 68) zumindest eine ebene Fläche (22; 72) darbietet und die ebene Fläche des Schneidelementes innerhalb eines Zahns (10; 66) derart orientiert ist, daß sie zumindest teilweise eine Vorlauffläche des Zahns (10; 66) bildet, wie sie durch die Bewegungsrichtung des Zahns (10; 66) während eines normalen Schneidvorgangs bei rotierendem Meißel (34) definiert ist, dadurch gekennzeichnet, daß ein Ende der zylindrischen Gestalt zu einem konischen Segment geformt ist, jedes Schneidelement (12; 68) direkt in der Matrix des Meißels (34) während der Matrixbildung angebracht ist, und ein nachlaufendes Stützmittel (26; 78) vorgesehen ist, das integral mit der Meißeloberfläche (18) ausgefuhrt ist und sich in spitz zulaufender Form von der Meißeloberfläche (18) zu einer Nachlauffläche (28; 74) des Schneidelements (12; 68) erstreckt, wobei die Schräge des konisch geformt Segments annähernd mit der Schräge der Nachlaufstütze (26; 78) zusammenfällt.
2. Drehbohrmeißel nach Anspruch 1, bei dem das Segment des zylindrisch geformten Schneidelementes ein Halbzylindersegment (68) bildet, das dementsprechend eine entlang einem Durchmesser der Zylinder verlaufende Vorlauffläche (72) definiert.
3. Drehbohrmeißel nach Anspruch 1, bei dem das Segment des zylindrisch geformten Schneidelementes ein Viertelsegment (12) bildet, das dementsprechend eine Scheitelkante (20) und zwei Vorlaufflächen (22) definiert, die einen spitzen Winkel hinter der Scheitelkante bilden, der annahernd 90° beträgt.
4. Drehbohrmeißel nach Anspruch 3, bei dem das zylindrisch geformte Schneidelement eine Längsachse (16) aufweist, die sich entlang der Scheitelkante (20) erstreckt, und bei dem das Schneidelement (12) derart zur Meißeloberfläche (18) ausgerichtet ist, daß die Längsachse (16) annähernd senkrecht zu ihr verläuft.
5. Drehbohrmeißel nach Anspruch 3 oder 4, bei dem ein Kanal (24) in der Meißeloberfläche (18) unmittelbar vor dem Diamantschneidelement (12; 68) ausgebildet ist und die Scheitelkante (20) an der benachbarten Wand des Flüssigkeitskanals (24) gelegen ist und wenigstens als Teil derselben dient.
6. Drehbohrmeißel nach einem der Ansprüche 1 bis 5, bei dem eine Mehrzahl von Reihen von Zähnen (16; 66) auf dem Meißel angeordnet sind und die Reihen paarweise zusammengefaßt sind und eine erste und zweite zugehörige Reihe bilden, der räumliche Abstand zwischen Zähnen (10a, 10b; 10c) innerhalf der ersten und der zweiten Reihe im wesentlichen konstant ist, die Zähn (10c) der zweiten Reihe hinter den zähnen (10a, 10b) der ersten Reihe angeordnet sind, und zwar hinter im Sinne der tangentialen Bewegung der Zähne während des Umlaufens des Meißels (34) bei normalen Schneidvorgängen, die Zähne (10c) der zweiten Reihe etwa mittig zwischen den Zähnen (10a; 10b) der ersten Reihe angeordnet sind, wodurch die Zähnen (10a; 10b; 10c) der ersten und der zweiten Reihen einen gleichförmigen Ringbereich schneiden, da der Meißel (34) mit höher wirksamer Zahndichte rotiert, als sie durch die Zahndichte innerhalb der ersten oder zweiten Reihe alleine erreichbar ist, und bei dem die Zähne (10c) der zweiten Reihe den Zähnen der ersten Reihe (10a, 10b) im Zwischenraum zwischen und hinter den Zähnen (10a; 10b) der ersten Reihe nachfolgen.
7. Drehbohremeißel nach Anspruch 1, bei dem der Meißel einen Kalibrierbereich (36) und eine schräge Schulter (38) aufweist, die Zähne (56, 58) auf der Schulter (38) nahe dem Kalibrierbereich (36) angeordnet sind und sich über der Meißeleberfläche (18) mit einem ersten vorbestimmten Abstand erstrecken, der Kalibrierbereich (36) Schneidelemente aufweist, die sich über der Meißeloberfläche (18) des Kalibrierbereiches (36) mit einem zweitenvorbestimmten Abstand erstrekken, der Meißel (34) ferner eine längsgerichtete Rotationsachse aufweist, die radiale Entfernung der auf dem Kalibrierbereich angeordneten und sich vorerstreckenden Schneidelemente (46) zur längsgerichteten Rotationsachse gleiche ist dem radialen Abstand eines zuoberst auf der Schulter (38) angeordneten Schniedelements (56) der Diamantschneidelemente (56, 58) zur längsgerichtent Rotationsachse, das oberste Schneidelement (56) auf der Schulter (38) auf dieser nächst dem Kalibrierbereich (36) an einer Stelle angeordnet ist, bei der die radialen Entfernungen der Schniedelemente (46) auf dem Kalibrierbereich (36) und des obersten Schneidelements (56) zur längsgerichteten Rotationsachse annähernd gleich sind.
8. Drehbohrmeißel nach einem der Ansprüche 1 bis 7, bei dem die Zylinderform des Schneidelementes ein Kreiszylinder ist.
9. Drehbohrmeißel nach einem der Ansprüche 3 bis 6, bei dem das Segment des zylindrisch geformten Schneidelements ein Viertelsegment (12) eines Vollzylinders ist und die Scheitelkante (20) entlang dessen Länngsachse (16) verläuft.
10. Drehbohrmeißel nach einem der Ansprüche 1 oder 9, bei dem das Schneidelement (12) in jedem Zahn (10) so angeordnet ist, daß jede Scheitelkante (20) den Vorlaufbereich des Schneidelementes (12) bildet.
11. Derhbohrmeißel nach Anspruch 10 bei, dem die tangentiale Bewegungsrichtung des Zahns (10) sich annähernd entlang der Winkelhalbierenden des die Scheitelkante (20) definieren spitzen Winkels verläft.
12. Drehbohrmeißel nach Anspruch 1 oder 2, bei dem das Schneidelement (12) eine Wandung eines benachbarten, in der Meißeloberfläche (18) vor dem Zahn angeordneten Flüssigkeitskanals (24) bildet.
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)

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

Family

ID=23894393

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84102985A Expired - Lifetime EP0119620B1 (de) 1983-03-21 1984-03-19 Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen

Country Status (7)

Country Link
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 (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 (de) * 1983-02-24 1984-09-05 Eastman Christensen Company Schneidzahn und Drehbohrmeissel mit einem ganz hervorstehenden polykristallinen Diamantelement

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 (de) * 1983-02-24 1984-09-05 Eastman Christensen Company Schneidzahn und Drehbohrmeissel mit einem ganz hervorstehenden polykristallinen Diamantelement

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

Similar Documents

Publication Publication Date Title
EP0658682B1 (de) Kaliberschneideinsatz für Rollenmeissel
US6050354A (en) Rolling cutter bit with shear cutting gage
US5655612A (en) Earth-boring bit with shear cutting gage
US6009963A (en) Superabrasive cutting element with enhanced stiffness, thermal conductivity and cutting efficiency
EP0164297B1 (de) Diamantbohrmeissel mit unterschiedlichen Schneideelementen
EP0117506B1 (de) Schneidzahn und Drehbohrmeissel mit einem ganz hervorstehenden polykristallinen Diamantelement
EP0841463B1 (de) Vorgeformtes Schneidelement für Drehbohrmeissel
EP0127077B1 (de) Drehbohrmeissel
US4883132A (en) Drag bit for drilling in plastic formation with maximum chip clearance and hydraulic for direct chip impingement
EP0285678B1 (de) Bohrmeissel für weiche bis harte Formationen
EP0314953B1 (de) Drehbohrmeissel
CA1237121A (en) Rotary drill bits and cutting elements for such bits
US5078219A (en) Concave drag bit cutter device and method
EP0687799A1 (de) Verbesserungen an oder bezüglich, mit einem superharten Material bekleideten, Elementen
NO163028B (no) Skjaerelement for en borkrone.
USRE33757E (en) Diamond drill bit with varied cutting elements
GB2218131A (en) Improvements in or relating to rotary drill bits
EP0186408B1 (de) Schneidelement für Drehbohrmeissel
EP0291314A2 (de) Schneidelement und Drehbohrmeissel mit einem derartigen Element
EP0188360B1 (de) Schneidwerkzeug für drehende Bohrmeissel
EP0121124B1 (de) Mit einem Diamantschneidelement versehener Drehbohrmeissel
CA1218353A (en) Tooth design to avoid shearing stresses
AU5278990A (en) An excavating tooth for an earth auger
US5143163A (en) Digging tooth
EP0119620B1 (de) Zahnbauart bei Verwendung von zylindrischen Diamantschneidelementen

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): BE CH DE FR GB LI NL

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Designated state(s): BE CH DE FR GB LI NL

17P Request for examination filed

Effective date: 19860422

17Q First examination report despatched

Effective date: 19870721

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: EASTMAN CHRISTENSEN COMPANY

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE DE FR GB NL

REF Corresponds to:

Ref document number: 3481435

Country of ref document: DE

Date of ref document: 19900405

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19910215

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19910321

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19910327

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19910331

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19910626

Year of fee payment: 8

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19920319

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Effective date: 19920331

BERE Be: lapsed

Owner name: EASTMAN CHRISTENSEN CY

Effective date: 19920331

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19921001

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
GBPC Gb: european patent ceased through non-payment of renewal fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19921130

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19921201

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST