EP0192016B1 - Trépan rotatif - Google Patents

Trépan rotatif Download PDF

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Publication number
EP0192016B1
EP0192016B1 EP85850056A EP85850056A EP0192016B1 EP 0192016 B1 EP0192016 B1 EP 0192016B1 EP 85850056 A EP85850056 A EP 85850056A EP 85850056 A EP85850056 A EP 85850056A EP 0192016 B1 EP0192016 B1 EP 0192016B1
Authority
EP
European Patent Office
Prior art keywords
drill bit
cutter elements
recess
protrusion
peripheral edge
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
Application number
EP85850056A
Other languages
German (de)
English (en)
Other versions
EP0192016A1 (fr
Inventor
Mahlon D. Dennis
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.)
Strata Bit Corp
Original Assignee
Strata Bit Corp
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 Strata Bit Corp filed Critical Strata Bit Corp
Priority to EP85850056A priority Critical patent/EP0192016B1/fr
Priority to DE8585850056T priority patent/DE3567054D1/de
Publication of EP0192016A1 publication Critical patent/EP0192016A1/fr
Application granted granted Critical
Publication of EP0192016B1 publication Critical patent/EP0192016B1/fr
Expired 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
    • E21B10/42—Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits
    • E21B10/43—Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits characterised by the arrangement of teeth or other cutting elements
    • 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
    • E21B10/02—Core bits
    • E21B10/04—Core bits with core destroying means
    • 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
    • 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
    • E21B10/60—Drill bits characterised by conduits or nozzles for drilling fluids
    • 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 rotary drill bit for cutting in earth formations, comprising a bit body including a cutting face having a peripheral edge and a central recess extending longitudinally inwardly from said peripheral edge, a plurality of fluid discharge nozzles mounted in said cutting face for emitting drilling fluid under pressure, and a plurality of cutter elements, some of which being mounted in said peripheral edge, and others of which being mounted in said recess to fracture an earthen core formed as the drill cuts through the formation, and that the drill bit further comprises a plurality of lateral discharge passages formed in said body, said passages extending radially through said body from said recess and extending longitudinally to said peripheral edge to form circumferential interruptions in said peripheral edge, and a convex protrusion ' disposed centrally at a longitudinally inner end of said recess and including a convex deflecting surface, said protrusion arranged to contact and fracture the earthen core.
  • a rotary drill bit In a typical rotary drilling operation, a rotary drill bit is rotated while being advanced into a soil or rock formation. The soil or rock is cut by cutting elements on the drill bit, and these cuttings are flushed from the borehole by the circulation of drilling fluid toward the top of the borehole.
  • the drilling fluid is delivered to the drill bit downwardly through a passage in the drill stem and is ejected outwardly through nozzles disposed in the cutting face of the drill bit.
  • the ejected drilling fluid is directed outwardly through the nozzles at high speed to aid in cutting, and to flush the cuttings and cool the cutter elements.
  • a traditional area of concern in the design of rotary drill bits of this type involves the configuration at the center of rotation of the bit cutting face where the linear speed of the cutter elements is relatively slow.
  • Drill bits of the above-described type are subject to certain shortcomings, however, as determined by the present inventor.
  • an unbalanced force pattern is established on the drill bit. That is, the force generated by the contact between core and the inclined surface includes a radial component which tends to displace the drill bit from its intended travel path. As a result, it becomes difficult to cut in a predetermined straight path.
  • Another object is to provide a drill bit which has utility in hard and soft substances and which promotes drilling in a straight direction.
  • a further object is to provide such a drill bit which minimizes tendencies for drilling fluid to bypass the cutter elements.
  • An additional object is to provide a centrally recessed drill bit which fractures a core without generating appreciable unbalanced forces on the bit.
  • a further object is to provide such a drill with a dam that deflects drilling fluid toward cutter elements which otherwise would be bypassed.
  • Fig. 1 is a side elevational view, partially in longitudinal section, of a drill bit and drill string according to the present invention.
  • a rotary drill bit 10 mounted at the end of a drill stem 11.
  • a plurality of small bores 12 are formed in the drill bit body 10 which are adapted to receive cutter elements 14 (Fig. 3).
  • the cutter elements 14 may comprise polycrystalline diamond studs in a conventional manner.
  • a plurality of larger bores 16 are provided in the drill bit for the reception of nozzles 18 for discharging jets of drilling fluid.
  • the drilling fluid is conducted to the nozzles 18 through a passage 20 in the drill stem 11 and drill bit 10 which communicates with passages 22 in the drill bit.
  • the jet streams aid in the cutting of the formation, cooling of the drill bit cutters, and carrying of the cuttings to the top of the borehole.
  • the cutting face 24 of the drill bit comprises an outer peripheral edge 26 and a central recess 28.
  • the outer edge 26 slopes longitudinally inwardly (upwardly) and radially outwardly.
  • the recess 28 is defined by side walls 30 which are inclined longitudinally and radially inwardly.
  • the cutting elements 14 are positioned in the peripheral edge 26, in the side walls 30, and in a floor 32 of the recess 28. Most of the nozzles 18 are positioned in the floor 32.
  • the floor 32 of the recess 28 is of concave configuration, the floor preferably comprising a centrally located, generally frusto-conical protuberance 34. If desired, the protuberance 34 could be of other convex shape such as semispherical for example. Holes 12A, 12B for cutting elements 14 (Fig. 2) are formed in the protuberance 34, and the aforementioned nozzle 18A is mounted in the protuberance 34.
  • the drill bit also includes a plurality of lateral discharge passages 36 which communicate with the central recess 28.
  • Those passages 36 include base surfaces 38 (Fig. 4) which constitute continuations of an inclined wedge face 40 of the protuberance 34.
  • the passages 36 preferably three in number, are equidistantly spaced around the longitudinal axis of the drill bit, i.e. at 120 degree intervals.
  • Each passage extends radially completely through the bit body and extends longitudinally outwardly to the peripheral edge 26 so as to form gaps in the latter.
  • the earth formation is cut so as to form a conical earthen core which projects into the central recess 28.
  • the core is fractured by the combined action of the cutting elements 14 and the convex protuberance 34, the former engaging the sides of the core and the apex 41 of the latter engaging the tip of the core.
  • the convex shape of the surface 40 of the protuberance 34 assures that the reaction forces applied against the protuberance will be distributed around the protuberance and thus will tend to be self-balancing in the radial direction. That is, a concentration of forces at one point on the floor of the recess is avoided. As a result, the drill bit will not be caused to deviate from its intended path of travel by unbalanced forces acting on the floor of the recess.
  • the cuttings are discharged from the recess through the passages 36 by the action of the surface 40 which serves as a wedge, and by flushing fluid from the nozzles 18, 18A.
  • the ridge 50 can be formed of a hard or a soft substance, as desired.
  • the ridge 50 can be formed of a hard material such as tungsten carbide or 4140 steel, or formed of a softer substance such as a soft steel (e.g. 1020 steel).
  • the ridge 50 projects outwardly from the cutting face by a distance slightly less than that of the cutter elements 14 and extends longitudinally along the side wall of the recess and radially along the peripheral edge 26.
  • the ridge 50 performs two important functions. Firstly, the ridge acts to dam-up drilling fluid ejected from the adjacent trailing nozzle 188 (i.e. the nearest nozzle 18B spaced clockwise from the ridge 50 in Fig. 2). That is, in the absence of the ridge, much of the drilling fluid emanating from that nozzle would flow into the adjacent gap in the peripheral edge (i.e., the gap formed by the discharge passage) and then upwardly through the annulus. However, upon encountering the ridge 50, the fluid level is blocked, causing the fluid to rebound and flow to the adjacent cutting elements located behind the ridge, i.e. the cutting elements spaced clockwise from the ridge 50 in Fig. 2.
  • the ridges 50 project from the cutting face 24 by a distance less than, e.g. one-half, that of the cutter elements 14. The difference in such projecting distance is about equal to the expected penetration depth of the cutter elements. In this fashion, the ridge will essentially contact the formation, thereby minimizing the travel of fluid between the ridge and the formation.
  • a second important function of the ridge 50 is to act as a plow to push larger cuttings from the associated discharge passage so that such cuttings do not contact and damage the cutting elements located behind the ridge.
  • the ridges 50 may serve as cutter blades as well as plows.
  • the drill bit is rotated while simultaneously advanced into an earth formation.
  • an earthen core is formed which is disposed within the recess 28.
  • the sides of the core are gradually fractured by the cutter elements 14 disposed within the recess, and the tip of the earthen core is fractured by the cutter elements disposed in the floor of the recess, as well as by the convex protuberance 34.
  • Engagement between the core and the protuberance is such as to establish generally radially balanced forces on the drill bit whereby the drill bit is not diverted from its intended path of travel.
  • the convex protuberance 34 deflects the cuttings laterally outwardly through the discharge passages 36. Ejection of larger chunks through the discharge passages is aided by the ridges 50 which act as plows to push the chunks along.
  • the ridges 50 also serve to block the escape of drilling fluid from the nozzles 18. Instead, that fluid rebounds rearwardly and flows across the cutter elements disposed behind the respective ridges in order to flush and cool those cutter elements.
  • the present invention minimizes the likelihood that unbalanced radial forces will be exerted against the drill bit in response to contact between the earthen core and the floor of the recess. Consequently, it is easier to maintain the drill bit in a straight path of travel.
  • the presence of the ridges 50 aids in pushing larger chunks through the lateral discharge openings and thereby minimizes the likelihood that such chunks could contact and damage the cutter elements.

Landscapes

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

Claims (10)

1. La présente invention concerne un trépan rotatif pour forer des formations de sol, comportant un corps de trépan (10) comprenant une face de coupe (24) présentant un bord périphérique (26) et une cavité centrale (28) s'étendant longitudinalement vers l'intérieur à partir dudit bord périphérique (26), une pluralité d'ajutages (18) de sortie de fluide montés dans ladite face de coupe (24) pour déliverer sous pression du fluide de forage, et une pluralité d'éléments de coupe (14) dont certains sont montés dans ledit bord périphérique (26), les autres, étant montés dans ladite cavité (28) pour fracturer un noyau de sol formé lors du forage de la formation par le trépan, le trépan comportant en outre une pluralité de passages latéraux (36) de sortie ménagés dans ledit corps (10), lesdits passages (36) s'étendant radialement à travers ledit corps (10) à partir de ladite cavité (28) et s'étendant longitudinalement jusqu'audit bord périphérique (26) pour constituer des interruptions circonféren- cielles sur ledit bord périphérique (26), et une saillie convexe (34) située centralement à une extrémité longitudinalement intérieure de ladite cavité (28) et présentant une surface convexe (40) de déviation, ladite saillie (34) étant agencée pour venir en contact et fracturer le noyau de sol, caractérisé en ce que les débris de forage sont déviés vers lesdits passages latéraux (36) de sortie qui s'étendent longitudinalement vers l'arrière au-delà de ladite saillie (34).
2. Un trépan selon la revendication 1, comportant une nervure (50) disposée le long d'un bord avant de chacun desdits passages de sortie (36), chaque nervure (50) faisant saillie de ladite face de coupe (24) sur une distance inférieure à celle desdits éléments de coupe (14) et étant agencée pour retarder l'écoulement du fluide de forage dans le passage associé (36) de sortie à partir d'un adjutage adjacent (18), de sorte que ce fluide est amené à circuler à travers les éléments de coupe (14) situés derrière ladite nervure (50).
3. Un trépan selon la revendication 1, dans lequel ladite saillie (34) est de forme tronconique.
4. Un trépan selon la revendication 3, dans lequel la surface de base (38) de chaque passage (36) constitue un prolongement d'une face inclinée (40) en forme de coin de la saillie (34).
5. Un trépan selon l'une quelconque des revendications précédentes, dans lequel l'ensemble desdits éléments de coupe (14) sont disposés dans ladite cavité (28) et sur ledit bord périphérique (26), et ladite saillie (34) étant disposée longitudinalement en arrière par rapport à tous les éléments de coupe sur ledit bord périphérique (26).
6. Un trépan selon l'une quelconque des revendications précédentes, dans lequel certains desdits ajutages (18) sont montés dans une paroi latérale (30) de ladite cavité (28) et l'un (18A) desdits ajutages est monté dans ladite saillie (34).
7. Un trépan selon l'une quelconque des revendications précédentes, dans lequel au moins l'un desdits éléments de coupe (14) est monté dans ladite saillie (34).
8. Un trépan selon l'une quelconque des revendications précédentes, dans lequel lesdits passages de sortie (36) sont au nombre de trois, lesdits passages étant disposés de manière équidistante sur la périphérie dudit trépan.
9. Un trépan selon l'une quelconque des revendications 2 à 8, dans lequel lesdits éléments de coupe (14) font saillie, par rapport à ladite face de coupe (24), au-delà desdites nervures (50) sur une distance égale à la profondeur de pénétration prévue desdits éléments de coupe (14).
10. Un trépan selon l'une quelconque des revendications 2 à 8, dans lequel lesdites nervures (50) font saillie par rapport à ladite face de coupe d'une distance égale à environ la moitié de la distance dont lesdits éléments de coupe (14) font saillie par rapport à ladite surface de coupe (24).
EP85850056A 1985-02-19 1985-02-19 Trépan rotatif Expired EP0192016B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP85850056A EP0192016B1 (fr) 1985-02-19 1985-02-19 Trépan rotatif
DE8585850056T DE3567054D1 (en) 1985-02-19 1985-02-19 Rotary drill bit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP85850056A EP0192016B1 (fr) 1985-02-19 1985-02-19 Trépan rotatif

Publications (2)

Publication Number Publication Date
EP0192016A1 EP0192016A1 (fr) 1986-08-27
EP0192016B1 true EP0192016B1 (fr) 1988-12-28

Family

ID=8194705

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85850056A Expired EP0192016B1 (fr) 1985-02-19 1985-02-19 Trépan rotatif

Country Status (2)

Country Link
EP (1) EP0192016B1 (fr)
DE (1) DE3567054D1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8186456B2 (en) 2008-02-01 2012-05-29 Pdti Holdings, Llc Methods of using a particle impact drilling system for removing near-borehole damage, milling objects in a wellbore, under reaming, coring, perforating, assisting annular flow, and associated methods

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7503407B2 (en) 2003-04-16 2009-03-17 Particle Drilling Technologies, Inc. Impact excavation system and method
US8342265B2 (en) 2003-04-16 2013-01-01 Pdti Holdings, Llc Shot blocking using drilling mud
US7793741B2 (en) 2003-04-16 2010-09-14 Pdti Holdings, Llc Impact excavation system and method with injection system
US7798249B2 (en) 2003-04-16 2010-09-21 Pdti Holdings, Llc Impact excavation system and method with suspension flow control
US7258176B2 (en) * 2003-04-16 2007-08-21 Particle Drilling, Inc. Drill bit
US7997355B2 (en) 2004-07-22 2011-08-16 Pdti Holdings, Llc Apparatus for injecting impactors into a fluid stream using a screw extruder
US7987928B2 (en) 2007-10-09 2011-08-02 Pdti Holdings, Llc Injection system and method comprising an impactor motive device
US7980326B2 (en) 2007-11-15 2011-07-19 Pdti Holdings, Llc Method and system for controlling force in a down-hole drilling operation
US8485279B2 (en) 2009-04-08 2013-07-16 Pdti Holdings, Llc Impactor excavation system having a drill bit discharging in a cross-over pattern

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2740612A (en) * 1954-02-23 1956-04-03 Phipps Orville Two-arm rotary drill bit
FR1197183A (fr) * 1958-05-29 1959-11-27 J K Smit & Fils Ets Perfectionnements apportés aux têtes de forage diamantées
FR1363375A (fr) * 1963-05-02 1964-06-12 Outil à balayage frontal
FR1366092A (fr) * 1963-05-27 1964-07-10 Aquitaine Petrole Outil rotatif perfectionné de forage
US3938599A (en) * 1974-03-27 1976-02-17 Hycalog, Inc. Rotary drill bit
FR2385883A1 (fr) * 1977-03-31 1978-10-27 Petroles Cie Francaise Outil de forage a haut rendement a attaque rapide de la carotte
US4397363A (en) * 1980-01-10 1983-08-09 Drilling & Service U.K. Limited Rotary drill bits and method of use
US4352400A (en) * 1980-12-01 1982-10-05 Christensen, Inc. Drill bit
US4494618A (en) * 1982-09-30 1985-01-22 Strata Bit Corporation Drill bit with self cleaning nozzle
FR2538442B1 (fr) * 1982-12-23 1986-02-28 Charbonnages De France Taillant pour foration rotative assistee par jet

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8186456B2 (en) 2008-02-01 2012-05-29 Pdti Holdings, Llc Methods of using a particle impact drilling system for removing near-borehole damage, milling objects in a wellbore, under reaming, coring, perforating, assisting annular flow, and associated methods
US8353367B2 (en) 2008-02-01 2013-01-15 Gordon Tibbitts Methods of using a particle impact drilling system for removing near-borehole damage, milling objects in a wellbore, under reaming, coring perforating, assisting annular flow, and associated methods
US8353366B2 (en) 2008-02-01 2013-01-15 Gordon Tibbitts Methods of using a particle impact drilling system for removing near-borehole damage, milling objects in a wellbore, under reaming, coring, perforating, assisting annular flow, and associated methods

Also Published As

Publication number Publication date
DE3567054D1 (en) 1989-02-02
EP0192016A1 (fr) 1986-08-27

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