US3838742A - Drill bit for abrasive jet drilling - Google Patents

Drill bit for abrasive jet drilling Download PDF

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Publication number
US3838742A
US3838742A US00389569A US38956973A US3838742A US 3838742 A US3838742 A US 3838742A US 00389569 A US00389569 A US 00389569A US 38956973 A US38956973 A US 38956973A US 3838742 A US3838742 A US 3838742A
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drill bit
face plates
nozzles
groove
ridges
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US00389569A
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Wold H Juvkam
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Chevron USA Inc
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Gulf Research and Development Co
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Priority to US00389569A priority Critical patent/US3838742A/en
Priority to CA196,519A priority patent/CA986088A/en
Priority to GB3127874A priority patent/GB1446828A/en
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Assigned to CHEVRON RESEARCH COMPANY, SAN FRANCISCO, CA. A CORP. OF DE. reassignment CHEVRON RESEARCH COMPANY, SAN FRANCISCO, CA. A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: GULF RESEARCH AND DEVELOPMENT COMPANY, A CORP. OF DE.
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    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B7/00Special methods or apparatus for drilling
    • E21B7/18Drilling by liquid or gas jets, with or without entrained pellets
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00Drill bits
    • E21B10/46Drill bits characterised by wear resisting parts, e.g. diamond inserts
    • E21B10/56Button-type inserts
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00Drill bits
    • E21B10/60Drill bits characterised by conduits or nozzles for drilling fluids

Definitions

  • Each of a plurality of geng 3 erally sectorially shaped face plates of abrasive resistant material has a wedge extending over the full [56] References Cited width of the face plate positioned to ride on the ridge on each side of a groove cut by the stream discharged UNITED STATES PATENTS from a nozzle in a different face plate. 3,384,192 5/1968 Goodwin et al.
  • Abrasive jet drilling has recently been developed for drilling wells through very hard formations in which the drilling rate that can be obtained using conventional rotary drilling operations is so slow that the cost of drilling by such methods becomes excessive.
  • an abrasive such as steel particles is suspended in a liquid that is pumped down through the drill string and discharged from nozzles in a bit at the lower end of the drill string.
  • the abrasive laden liquid is discharged at a high velocity such as may be obtained by a pressure drop of 5,000 to 10,000 psi, or even more, through the nozzles.
  • the nozzles are positioned in the lower end of the drill bit such that the abrasive laden streams cut in the bottom of the borehole a plurality of concentric grooves separated by thin, easily broken ridges.
  • the ridges separating the grooves are thin mechanically broken byengagement with the drill bit.
  • This invention relates to a drill bit for abrasive jet drilling in which a plurality of face plates of generally sectorial shape cover the lower end of the drill bit.
  • the face plates are separated by passages to permit flow of drilling liquid and cuttings from below the bit.
  • Nozzles extending through the lower end of the bit and face plates are positioned to discharge high velocity streams of abrasive laden drilling liquid that cut in the bottom of the borehole a plurality of concentric grooves, the largest of which is around the perimeter of the borehole.
  • the grooves are separated by thin, easily broken ridges.
  • the lower surface of the face plates includes an arcuate wedge extending over the full width of the face plates in a position to extend into alternate grooves cut in the bottom of the borehole and ride on the ridges separating the grooves to mechanically break those ridges.
  • the wedge on a face plate extends into grooves cut by abrasive streams discharged from nozzles that have their outlet opening through a different face plate.
  • FIG. 1 is a vertical sectional view taken along section line Il in FIG. 3 of a drill bit constructed in accordance with this invention.
  • FIG. 2 is an elevation view of the lower portion of the drill bit body.
  • FIG. 3 is a plan view of the bottom of the bit showing the position of the nozzles and arcuate wedges.
  • FIG. 4 is a vertical sectional view along the section line IV-IV in FIG. 3.
  • FIG. 5 is a vertical sectional view, similar to FIG. 4, along the section line VV in FIG. 3.
  • FIG. 6 is a vertical sectional view along the section line VI-VI in FIG. 3.
  • FIG. 7 is a diagrammatic representation of the bottom of the borehole in cross section showing the relative positions of nozzles and wedges with respect to grooves cut in the bottom of the borehole.
  • a drill bit indicated generally by reference numeral 10 having a drill bit body 12 connected at its upper end to an adaptor 14 provided with threads 16 for connection to the lower end of a drill string, not shown.
  • the drill bit 10 is of generally tubular shape open at its upper end to receive drilling liquid from the drill string. As is best shown in FIG.
  • the outer surface of drill bit body 12 has a plurality of spaced apart lobes 18 separated by flutes 20 which provide passages between the drill bit body 12 and the borehole wall for the flow of drilling liquid and cuttings as hereinafter described.
  • the drill bit body 12 Extending downwardly through the drill bit 10 is a central passage 22 which is closed at the lower end of the drill bit by a bottom 24.
  • the drill bit body 12 for example, can be formed by drilling central opening 22 and machining flutes 20 in a solid piece of steel or can be cast in a single piece of the desired shape.
  • the lower surface of the bottom 24 of the drill bit body is flat except for tapered surfaces 26 between the lower ends of lobes 18 and extending along the lower surface of the bottom to the flutes 20 as is shown in FIGS. 3 and 5.
  • the outer surface of the lower end of the drill bit body and the tapered surfaces 26 preferably are covered by hard surfacing material 28 to reduce wear of the drill bit body by rebounding abrasive particles.
  • Wear buttons 30 of an abrasion resistant material protrude from the outer surface of the drill bit body 12 to protect the drill bit from abrasion by the borehole wall and to break ridges that may protrude from the borehole wall.
  • a face plate 32 of an abrasion resistant material such as a tungsten carbide alloy and of generally sectorial shape Secured to the bottom 24 under each of the lobes 18 is a face plate 32 of an abrasion resistant material such as a tungsten carbide alloy and of generally sectorial shape.
  • a preferred method of attaching the face plates 32 is to silver solder a copper plate 34 to the bottom surface of the bottom member 24 and silver solder the tungsten carbide face plates to the copper plate.
  • FIG. 3 of the drawings it will be noted that in the embodiment of the invention illustrated there are four lobes; however, the number of lobes may be larger or smaller and will depend on the size of the.
  • each of the radii defining the sides of the face plate is spaced from the center of the bit to provide space for a center protector 36 which tapers from a maximum thickness at the center of the bit to a minimum thickness at its outer ends, as is best shown in FIG. 2, to provide channels between the face plates for flow of drilling liquid and cuttings outwardly to the space between flutes 20 and the borehole wall.
  • the center protector 36 illustrated in FIG. 3 has wings 38 extending laterally outward from the center of the bit toward two flutes 20 to provide protection for the bottom of the drill bit body 12 from the abrasion by cuttings and drilling liquid flowing toward the flutes.
  • Center protector 36 like other parts of the drill bit exposed to rebounding abrasive particles is constructed of an abrasive-resistant material, preferably a tungsten carbide alloy.
  • nozzles 40 As shown in FIG. 1, the upper ends of a plurality of nozzles generally identified by reference numeral 40, open into the central opening 22 in the drill bit body.
  • the nozzles 40 extend through bottom 24 and face plates 32 with the lower ends of the nozzles substantially at the bottom surface of the face plates.
  • the nozzles are constructed of an abrasion resistant material, preferably a tungsten carbide alloy, to withstand the severely erosive conditions caused by the very high velocity stream of abrasive laden liquid passing through the nozzle.
  • nozzles are positioned to cut a central hole surrounded by a plurality of grooves, the outermost of which has an outer diameter equal to the borehole di ameter.
  • the central hole may have a center portion extending upwardly from the bottom as a result of the hole being cut by an outwardly slanting nozzle, but the upwardly extending portion should have its upper end eroded by an abrasive jet stream to such an extent that mechanical breaking of the center portion is easy or is not necessary.
  • an abrasive jet stream cuts a hole that leaves little if any rock at the center of the bore-- hole to be mechanically broken by the drill bit.
  • inwardly directed nozzles 40a discharge a stream to cut a central hole 42 (shown in FIG. 7) in the bottom of the borehole.
  • Verti cle nozzles 40b shown in FIGS. 3 and 6 discharge high velocity streams of abrasive laden liquid to cut a groove 44 separated from central hole 42 by a ridge 46.
  • Nozzles 40d shown in FIGS. 3 and l are positioned and slope outwardly to discharge a stream that cuts a groove 52 separated from groove 48 by ridge 54.
  • nozzle 4 slope outwardly and are positioned to discharge abrasive laden streams that cut groove 56 separated from groove 52 by ridge 58.
  • the outer wall of groove 56 is the borehole wall. Because of the greater amount of rock that must be removed to cut the grooves of larger diameter, the number of nozzles at a particular distance from the center of the bit increases as the distance from the center increases. Thus, there are in the embodiment shown five nozzles 402 and four nozzles 40d. Two each of nozzles 40a, 40b and 40c are provided. Although a single nozzle would be adequate to remove the rock in the central hole, two nozzles are provided as insurance against the possibility of a single nozzle becoming plugged.
  • the nozzles 40 can be held in position in the openings through bottom 24 and face plates by helical coils engaging grooves in the outer surface of the nozzles and in the wall of the openings, as disclosed in US. Pat. No. 3,688,852.
  • the face plates 32 differ slightly in configuration because of the difference in location and orientation of the nozzles extending through the face plates for discharge of high velocity streams of drilling liquid against the borehole bottom.
  • the upper left-hand face plate, designated as 32a has three nozzles 40e and two nozzles 40d extending through it.
  • the face plate at the upper right-hand portion of FIG. 3 is designated 32b. Nozzles 40a, 40b and 400 extend through that face plate.
  • Face plate 32d is identical to face plate 32b except for its position on the bottom of the drill bit.
  • arcuate wedge identified generally by numeral 60 positioned to extend into a groove cut in the bottom of the borehole and ride on the ridges forming the side walls of the groove.
  • Arcuate wedges 60 extend over substantially the full width of the face plates to a level below the outlet ends of the nozzles.
  • the term full width means that the arcuate wedge extends substantially from the radius defining one side of the face plate to the radius defining the opposite side.
  • the center of curvature of the wedges is the center of rotation of the drill bit.
  • Wedge 60a is positioned to extend into grooves 44 and ride on ridges 46 and 50.
  • a wedge 60b on face plate 32b extends downwardly in position to extend into groove 52 and ride on ridges 54 and 58.
  • Wedge 60c on the lower surface of face plate 32c is positioned at the same radial distancefrom the center of rotation of the drill bit as wedge 60a and is adapted to extend into groove 44 and ride on ridges 46 and 50.
  • Wedge 60d is at the same radial distance from the center of rotation of the bit as 60b and therefore extends into groove 52 and rides on ridges 54 and 58.
  • the wedges on the bottom of a face plate extend into grooves cut by high velocity streams discharged from nozzles that extend through a different face plate.
  • none of the wedges is subjected to severe erosion by rebounding abrasive particles moving at high velocity discharged from a nozzle close to, or having its outlet in, the wedge.
  • the drill bit In use, the drill bit is secured to the lower end of the drill string and lowered into the hole. Drilling liquid containing abrasive particles suspended therein is pumped down the drill string as the drill string is rotated. The pressure on the drilling liquid is such that the drilling liquid is discharged from the nozzles at a velocity of at least 650 feet per second.
  • the high velocity streams of drilling liquid discharged from the nozzles cut the central hole and the grooves 44, 48, 52 and 56 shown in FIG. 7 in the bottom of the borehole.
  • the arcuate wedges 60a and 600 on face plates 32a and 32c extend into the upper end of the groove 44 and ride on ridges 46 and 50.
  • Arcuate wedges 60b and 60d extend into grooves 52 and ride on ridges 54 and 58. It is only necessary that wedges extend into alternate grooves to subject each of the ridges 46, 50, 54 and 58 to mechanical stress by an arcuate wedge extending from the face plate of the drill bit.
  • Weight of approximately L000 lbs. per inch of diameter of the drill bit placed on the drill bit is adequate to break the ridges extending upwardly from the bottom of the borehole.
  • Rock broken from the ridges and eroded from the bottom by the abrasive stream is swept away by drilling liquid discharged from the nozzles and is carried upwardly between the outer surface of the bit and the borehole wall into the annulus surrounding the drill string.
  • the flutes in the lateral surface of the bit and the passages between the face plates facilitate flow of cuttings from the bottom of the borehole.
  • the single wedge in each of the face plates provides a massive element capable of withstanding impact placed on the wedges.
  • the substantial length of the wedges increases the stability of .the bit as it rotates at the bottom of the hole.
  • the positioning of wedges in one face plate to extend into grooves cut by nozzles that extend through a different face plate eliminates weakening of the wedges by holes for nozzles.
  • a drill bit adapted to be rotated by a drill string about a central axis for abrasive jet drilling comprising a hollow body closed at the lower end and adapted at its upper end for connection to the lower end of the drill string, a plurality of face plates of abrasive resistant material and generally sectorial shape extending from the lower end of the drill bit body, outlet passages between adjacent face plates for removal of cuttings from below the bit, a plurality of nozzles extending downwardly through the lower end of the bit and the face plates positioned to cut in the bottom of the hole being drilled a plurality of concentric grooves separated by ridges, and each of the face plates having an arcuate wedge extending downwardly over the full width of the face plates positioned to extend into a groove and ride on ridges forming the sides of the groove to break the ridges, said arcuate wedge having a center of curvature substantially at the axis of rotation of the drill bit.
  • a drill bit as set forth in claim 1 in which the nozzles cut a central hole that is surrounded by the concentric grooves.
  • a drill bit as set forth in claim 1 in which the wedges of each face plate are positioned to extend into grooves cut by the discharge of abrasive laden liquid through nozzles in a different face plate.
  • a drill bit as set forth in claim 3 in which there are four face plates and the wedges on opposite face plates are at the same radial distance from the axis of rotation of the drill bit.
  • a drill bit as set forth in claim 1 in which there are four face plates, the nozzles extending through the lower end of the drill bit are positioned to cut a central hole surrounded by four concentric grooves and the wedges extending from two opposite face plates ride on the ridges separating the first and second grooves and the ridge separating the second groove and the third groove and wedge extending from the other face plates ride on the ridge separating the third and fourth groove and on the ridge separating the fourth groove and the central hole.
  • a drill bit as set forth in claim 1 in which wedges are positioned to extend into alternate grooves whereby each ridge is engaged by at least one wedge.

Abstract

A drill bit for abrasive jet drilling of wells having a plurality of nozzles extending through the bottom of the bit in position to discharge high velocity jet streams that erode a plurality of concentric grooves in the bottom of the borehole. Each of a plurality of generally sectorially shaped face plates of abrasive resistant material has a wedge extending over the full width of the face plate positioned to ride on the ridge on each side of a groove cut by the stream discharged from a nozzle in a different face plate.

Description

Unlted States Patent 11 1 1111 3,838,742 Juvkam-Wold Oct. 1, 1974 [54] DRILL BIT FOR ABRASIVE JET DRILLING 3,542,142 11 1970 Hasiba et al. 175 422 x 3,583,503 6/1971 Coski et a1 175/336 X [75] Inventor: g J g 3,688,852 9/1972 Gaylord et a1. 175 393 onroevi e, a.
[73] Assignee: Gulf Research & Development Primary ExaminerJohn E. Murtagh C p y, Pittsburgh, Assistant Examiner-Richard E. Favreau [22] Filed: Aug. 20, I973 1211 Appl. No: 389,569 1571 ABSTRACT A drill bit for abrasive jet drilling of wells having a [52] us CL 75/380 l75/67 1'75/393 plurality of nozzles extending through the bottom of l75/422 the bit in position to discharge high velocity jet [51] Int. Cl E2lb 7/18 Streams that erode a plurality of concentric grooves in [58] Field Search 6 67 422 327 the bottom of the borehole. Each of a plurality of geng 3 erally sectorially shaped face plates of abrasive resistant material has a wedge extending over the full [56] References Cited width of the face plate positioned to ride on the ridge on each side of a groove cut by the stream discharged UNITED STATES PATENTS from a nozzle in a different face plate. 3,384,192 5/1968 Goodwin et al. 175/67 X 3,414,070 12/1968 Pekarek 175/393 6 Claims, 7 Drawing Figures AHMED BET I974 SHELEI 3 BF 3 DRILL lBIT FOR ABRASIVE .IET DRILLING This invention relates to the drilling of wells and more particularly to a drill bit for use in abrasive jet drilling.
Abrasive jet drilling has recently been developed for drilling wells through very hard formations in which the drilling rate that can be obtained using conventional rotary drilling operations is so slow that the cost of drilling by such methods becomes excessive. In the abrasive jet drilling process, an abrasive such as steel particles is suspended in a liquid that is pumped down through the drill string and discharged from nozzles in a bit at the lower end of the drill string. The abrasive laden liquid is discharged at a high velocity such as may be obtained by a pressure drop of 5,000 to 10,000 psi, or even more, through the nozzles. The nozzles are positioned in the lower end of the drill bit such that the abrasive laden streams cut in the bottom of the borehole a plurality of concentric grooves separated by thin, easily broken ridges. The ridges separating the grooves are thin mechanically broken byengagement with the drill bit.
In US. Pat. No. 3,542,142 of l-Iasiba et al. a drill bit for abrasive jet drilling is disclosed in which tapered buttons of a wear resistant material such as tungsten carbide extend from the lower end of the drill bit in position to ride on ridges separating the grooves and break the ridges. Similar means for breaking the ridges are disclosed in U.S. Pat. No. 3,548,959 of I-Iasiba. Tungsten carbide, while necessary to withstand the high erosive conditions below the drill bit, is relatively weak in tension and brittle, and it has been found that the buttons are frequently broken during use of the drill bit. Since mechanical breaking of the ridges is essential to rapid drilling, failure of the buttons will necessitate replacement of the drill bit.
This invention relates to a drill bit for abrasive jet drilling in which a plurality of face plates of generally sectorial shape cover the lower end of the drill bit. The face plates are separated by passages to permit flow of drilling liquid and cuttings from below the bit. Nozzles extending through the lower end of the bit and face plates are positioned to discharge high velocity streams of abrasive laden drilling liquid that cut in the bottom of the borehole a plurality of concentric grooves, the largest of which is around the perimeter of the borehole. The grooves are separated by thin, easily broken ridges. The lower surface of the face plates includes an arcuate wedge extending over the full width of the face plates in a position to extend into alternate grooves cut in the bottom of the borehole and ride on the ridges separating the grooves to mechanically break those ridges. In the preferred embodiment of this invention, the wedge on a face plate extends into grooves cut by abrasive streams discharged from nozzles that have their outlet opening through a different face plate.
In the drawings:
FIG. 1 is a vertical sectional view taken along section line Il in FIG. 3 of a drill bit constructed in accordance with this invention.
FIG. 2 is an elevation view of the lower portion of the drill bit body.
FIG. 3 is a plan view of the bottom of the bit showing the position of the nozzles and arcuate wedges.
FIG. 4 is a vertical sectional view along the section line IV-IV in FIG. 3.
FIG. 5 is a vertical sectional view, similar to FIG. 4, along the section line VV in FIG. 3.
FIG. 6 is a vertical sectional view along the section line VI-VI in FIG. 3.
FIG. 7 is a diagrammatic representation of the bottom of the borehole in cross section showing the relative positions of nozzles and wedges with respect to grooves cut in the bottom of the borehole.
Referring to FIG. 1, a drill bit indicated generally by reference numeral 10 is shown having a drill bit body 12 connected at its upper end to an adaptor 14 provided with threads 16 for connection to the lower end of a drill string, not shown. The drill bit 10 is of generally tubular shape open at its upper end to receive drilling liquid from the drill string. As is best shown in FIG.
2, the outer surface of drill bit body 12 has a plurality of spaced apart lobes 18 separated by flutes 20 which provide passages between the drill bit body 12 and the borehole wall for the flow of drilling liquid and cuttings as hereinafter described.
Extending downwardly through the drill bit 10 is a central passage 22 which is closed at the lower end of the drill bit by a bottom 24. In the construction of the drill bit of this invention, the drill bit body 12, for example, can be formed by drilling central opening 22 and machining flutes 20 in a solid piece of steel or can be cast in a single piece of the desired shape. The lower surface of the bottom 24 of the drill bit body is flat except for tapered surfaces 26 between the lower ends of lobes 18 and extending along the lower surface of the bottom to the flutes 20 as is shown in FIGS. 3 and 5. The outer surface of the lower end of the drill bit body and the tapered surfaces 26 preferably are covered by hard surfacing material 28 to reduce wear of the drill bit body by rebounding abrasive particles. Wear buttons 30 of an abrasion resistant material, preferably a tungsten carbide alloy, protrude from the outer surface of the drill bit body 12 to protect the drill bit from abrasion by the borehole wall and to break ridges that may protrude from the borehole wall.
Secured to the bottom 24 under each of the lobes 18 is a face plate 32 of an abrasion resistant material such as a tungsten carbide alloy and of generally sectorial shape. A preferred method of attaching the face plates 32 is to silver solder a copper plate 34 to the bottom surface of the bottom member 24 and silver solder the tungsten carbide face plates to the copper plate.
Referring to FIG. 3 of the drawings, it will be noted that in the embodiment of the invention illustrated there are four lobes; however, the number of lobes may be larger or smaller and will depend on the size of the.
drill bit. The inner end of each of the radii defining the sides of the face plate is spaced from the center of the bit to provide space for a center protector 36 which tapers from a maximum thickness at the center of the bit to a minimum thickness at its outer ends, as is best shown in FIG. 2, to provide channels between the face plates for flow of drilling liquid and cuttings outwardly to the space between flutes 20 and the borehole wall. The center protector 36 illustrated in FIG. 3 has wings 38 extending laterally outward from the center of the bit toward two flutes 20 to provide protection for the bottom of the drill bit body 12 from the abrasion by cuttings and drilling liquid flowing toward the flutes. Center protector 36, like other parts of the drill bit exposed to rebounding abrasive particles is constructed of an abrasive-resistant material, preferably a tungsten carbide alloy.
As shown in FIG. 1, the upper ends of a plurality of nozzles generally identified by reference numeral 40, open into the central opening 22 in the drill bit body. The nozzles 40 extend through bottom 24 and face plates 32 with the lower ends of the nozzles substantially at the bottom surface of the face plates. The nozzles are constructed of an abrasion resistant material, preferably a tungsten carbide alloy, to withstand the severely erosive conditions caused by the very high velocity stream of abrasive laden liquid passing through the nozzle. In the preferred embodiment illustrated in the drawings, nozzles are positioned to cut a central hole surrounded by a plurality of grooves, the outermost of which has an outer diameter equal to the borehole di ameter. The central hole may have a center portion extending upwardly from the bottom as a result of the hole being cut by an outwardly slanting nozzle, but the upwardly extending portion should have its upper end eroded by an abrasive jet stream to such an extent that mechanical breaking of the center portion is easy or is not necessary. Thus, in referring to cutting a central hole it is meant that an abrasive jet stream cuts a hole that leaves little if any rock at the center of the bore-- hole to be mechanically broken by the drill bit.
Referring to FIG. 3 and FIG. 1, inwardly directed nozzles 40a discharge a stream to cut a central hole 42 (shown in FIG. 7) in the bottom of the borehole. Verti cle nozzles 40b shown in FIGS. 3 and 6 discharge high velocity streams of abrasive laden liquid to cut a groove 44 separated from central hole 42 by a ridge 46. Outwardly slanting nozzles 40c shown in FIGS. 3 and discharge streams that cut a groove 48 separated from groove 44 by ridge 50. Nozzles 40d shown in FIGS. 3 and l are positioned and slope outwardly to discharge a stream that cuts a groove 52 separated from groove 48 by ridge 54. Nozzles 402 shown in FIG. 3 and FIG. 4 slope outwardly and are positioned to discharge abrasive laden streams that cut groove 56 separated from groove 52 by ridge 58. The outer wall of groove 56 is the borehole wall. Because of the greater amount of rock that must be removed to cut the grooves of larger diameter, the number of nozzles at a particular distance from the center of the bit increases as the distance from the center increases. Thus, there are in the embodiment shown five nozzles 402 and four nozzles 40d. Two each of nozzles 40a, 40b and 40c are provided. Although a single nozzle would be adequate to remove the rock in the central hole, two nozzles are provided as insurance against the possibility of a single nozzle becoming plugged. The nozzles 40 can be held in position in the openings through bottom 24 and face plates by helical coils engaging grooves in the outer surface of the nozzles and in the wall of the openings, as disclosed in US. Pat. No. 3,688,852.
In the embodiment illustrated in FIG. 3 of the drawings, the face plates 32 differ slightly in configuration because of the difference in location and orientation of the nozzles extending through the face plates for discharge of high velocity streams of drilling liquid against the borehole bottom. The upper left-hand face plate, designated as 32a, has three nozzles 40e and two nozzles 40d extending through it. The face plate at the upper right-hand portion of FIG. 3 is designated 32b. Nozzles 40a, 40b and 400 extend through that face plate. The face plate at the lower right portion of FIG.
3 is designated 320. Two nozzles 40e and two nozzles 40d extend through that face plate. At the lower left portion of FIG. 3 the face plate is designated as 32d to facilitate description of this invention. Face plate 32d is identical to face plate 32b except for its position on the bottom of the drill bit.
Extending downwardly from each of the face plates is an arcuate wedge identified generally by numeral 60 positioned to extend into a groove cut in the bottom of the borehole and ride on the ridges forming the side walls of the groove. Arcuate wedges 60 extend over substantially the full width of the face plates to a level below the outlet ends of the nozzles. The term full width means that the arcuate wedge extends substantially from the radius defining one side of the face plate to the radius defining the opposite side. The center of curvature of the wedges is the center of rotation of the drill bit.
The wedge extending downwardly from the lower surface of face plate 32a is designated 60a and is best shown in FIGS. 1 and 3 of the drawings. Wedge 60a is positioned to extend into grooves 44 and ride on ridges 46 and 50. A wedge 60b on face plate 32b extends downwardly in position to extend into groove 52 and ride on ridges 54 and 58. Wedge 60c on the lower surface of face plate 32c is positioned at the same radial distancefrom the center of rotation of the drill bit as wedge 60a and is adapted to extend into groove 44 and ride on ridges 46 and 50. Wedge 60d is at the same radial distance from the center of rotation of the bit as 60b and therefore extends into groove 52 and rides on ridges 54 and 58. It is an advantage of this invention that the wedges on the bottom of a face plate extend into grooves cut by high velocity streams discharged from nozzles that extend through a different face plate. Thus, none of the wedges is subjected to severe erosion by rebounding abrasive particles moving at high velocity discharged from a nozzle close to, or having its outlet in, the wedge.
In use, the drill bit is secured to the lower end of the drill string and lowered into the hole. Drilling liquid containing abrasive particles suspended therein is pumped down the drill string as the drill string is rotated. The pressure on the drilling liquid is such that the drilling liquid is discharged from the nozzles at a velocity of at least 650 feet per second.
The high velocity streams of drilling liquid discharged from the nozzles cut the central hole and the grooves 44, 48, 52 and 56 shown in FIG. 7 in the bottom of the borehole. The arcuate wedges 60a and 600 on face plates 32a and 32c extend into the upper end of the groove 44 and ride on ridges 46 and 50. Arcuate wedges 60b and 60d extend into grooves 52 and ride on ridges 54 and 58. It is only necessary that wedges extend into alternate grooves to subject each of the ridges 46, 50, 54 and 58 to mechanical stress by an arcuate wedge extending from the face plate of the drill bit.
Weight of approximately L000 lbs. per inch of diameter of the drill bit placed on the drill bit is adequate to break the ridges extending upwardly from the bottom of the borehole. Rock broken from the ridges and eroded from the bottom by the abrasive stream is swept away by drilling liquid discharged from the nozzles and is carried upwardly between the outer surface of the bit and the borehole wall into the annulus surrounding the drill string. The flutes in the lateral surface of the bit and the passages between the face plates facilitate flow of cuttings from the bottom of the borehole.
The single wedge in each of the face plates provides a massive element capable of withstanding impact placed on the wedges. The substantial length of the wedges increases the stability of .the bit as it rotates at the bottom of the hole. The positioning of wedges in one face plate to extend into grooves cut by nozzles that extend through a different face plate eliminates weakening of the wedges by holes for nozzles. By providing a single wedge in each of the face plates, interference with movement of particles broken from the ridges by the arcuate wedges is reduced to a minimum. Moreover, tensile stresses that might be developed by one wedge in a single face plate being forced outwardly while another is forced inwardly is avoided. Since tungsten carbide is relatively weak in tension, although highly resistant to abrasion, a single arcuate wedge in a face plate greatly reduces the chances of breaking the wedge from the face plate.
I claim:
1. A drill bit adapted to be rotated by a drill string about a central axis for abrasive jet drilling comprising a hollow body closed at the lower end and adapted at its upper end for connection to the lower end of the drill string, a plurality of face plates of abrasive resistant material and generally sectorial shape extending from the lower end of the drill bit body, outlet passages between adjacent face plates for removal of cuttings from below the bit, a plurality of nozzles extending downwardly through the lower end of the bit and the face plates positioned to cut in the bottom of the hole being drilled a plurality of concentric grooves separated by ridges, and each of the face plates having an arcuate wedge extending downwardly over the full width of the face plates positioned to extend into a groove and ride on ridges forming the sides of the groove to break the ridges, said arcuate wedge having a center of curvature substantially at the axis of rotation of the drill bit.
2. A drill bit as set forth in claim 1 in which the nozzles cut a central hole that is surrounded by the concentric grooves.
3. A drill bit as set forth in claim 1 in which the wedges of each face plate are positioned to extend into grooves cut by the discharge of abrasive laden liquid through nozzles in a different face plate.
4. A drill bit as set forth in claim 3 in which there are four face plates and the wedges on opposite face plates are at the same radial distance from the axis of rotation of the drill bit.
5. A drill bit as set forth in claim 1 in which there are four face plates, the nozzles extending through the lower end of the drill bit are positioned to cut a central hole surrounded by four concentric grooves and the wedges extending from two opposite face plates ride on the ridges separating the first and second grooves and the ridge separating the second groove and the third groove and wedge extending from the other face plates ride on the ridge separating the third and fourth groove and on the ridge separating the fourth groove and the central hole.
6. A drill bit as set forth in claim 1 in which wedges are positioned to extend into alternate grooves whereby each ridge is engaged by at least one wedge.

Claims (6)

1. A drill bit adapted to be rotated by a drill string about a central axis for abrasive jet drilling comprising a hollow body closed at the lower end and adapted at its upper end for connection to the lower end of the drill string, a plurality of face plates of abrasive resistant material and generally sectorial shape extending from the lower end of the drill bit body, outlet passages between adjacent face plates for removal of cuttings from below the bit, a plurality of nozzles extending downwardly through the lower end of the bit and the face plates positioned to cut in the bottom of the hole being drilled a plurality of concentric grooves separated by ridges, and each of the face plates having an arcuate wedge extending downwardly over the full width of the face plates positioned to extend into a groove and ride on ridges forming the sides of the groove to break the ridges, said arcuate wedge having a center of curvature substantially at the axis of rotation of the drill bit.
2. A drill bit as set forth in claim 1 in which the nozzles cut a central hole that is surrounded by the concentric grooves.
3. A drill bit as set forth in claim 1 in which the wedges of each face plate are positioned to extend into grooves cut by the discharge of abrasive laden liquid through nozzles in a different face plate.
4. A drill bit as set forth in claim 3 in which there are four face plates and the wedges on opposite face plates are at the same radial distance from the axis of rotation of the drill bit.
5. A drill bit as set forth in claim 1 in which there are four face plates, the nozzles extending through the lower end of the drill bit are positioned to cut a central hole surrounded by four concentric grooves and the wedges extending from two opposite face plates ride on the ridges separating the first and second grooves and the ridge separating the second groove and the third groove and wedge extending from the other face plates ride on the ridge separating the third and fourth groove and on the ridge separating the fourth groove and the central hole.
6. A drill bit as set forth in claim 1 in which wedges are positioned to extend into alternate grooves whereby each ridge is engaged by at least one wedge.
US00389569A 1973-08-20 1973-08-20 Drill bit for abrasive jet drilling Expired - Lifetime US3838742A (en)

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US00389569A US3838742A (en) 1973-08-20 1973-08-20 Drill bit for abrasive jet drilling
CA196,519A CA986088A (en) 1973-08-20 1974-04-01 Drill bit for abrasive jet drilling
GB3127874A GB1446828A (en) 1973-08-20 1974-07-15 Drill bits

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Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4262757A (en) * 1978-08-04 1981-04-21 Hydronautics, Incorporated Cavitating liquid jet assisted drill bit and method for deep-hole drilling
US4334585A (en) * 1980-07-14 1982-06-15 Smith International, Inc. Insert retention and cooling apparatus for drag bits
FR2566832A1 (en) * 1984-06-27 1986-01-03 Inst Francais Du Petrole METHOD AND IMPROVEMENT TO DRILLING TOOLS FOR HIGH EFFICIENCY IN CLEANING THE SIZE FRONT
FR2566833A1 (en) * 1984-06-27 1986-01-03 Inst Francais Du Petrole METHOD AND IMPROVEMENT TO DRILLING TOOLS HAVING WATER PASSAGES ENABLING GREAT EFFICIENCY IN CLEANING THE SIZE FRONT
US4768709A (en) * 1986-10-29 1988-09-06 Fluidyne Corporation Process and apparatus for generating particulate containing fluid jets
US4892159A (en) * 1988-11-29 1990-01-09 Exxon Production Research Company Kerf-cutting apparatus and method for improved drilling rates
US5145017A (en) * 1991-01-07 1992-09-08 Exxon Production Research Company Kerf-cutting apparatus for increased drilling rates
US5199512A (en) * 1990-09-04 1993-04-06 Ccore Technology And Licensing, Ltd. Method of an apparatus for jet cutting
US5291956A (en) * 1992-04-15 1994-03-08 Union Oil Company Of California Coiled tubing drilling apparatus and method
US5291957A (en) * 1990-09-04 1994-03-08 Ccore Technology And Licensing, Ltd. Method and apparatus for jet cutting
US5469926A (en) * 1994-04-22 1995-11-28 Bor-Mor, Inc. Directional boring drill bit blade
US5542486A (en) * 1990-09-04 1996-08-06 Ccore Technology & Licensing Limited Method of and apparatus for single plenum jet cutting
US5595252A (en) * 1994-07-28 1997-01-21 Flowdril Corporation Fixed-cutter drill bit assembly and method
US5862871A (en) * 1996-02-20 1999-01-26 Ccore Technology & Licensing Limited, A Texas Limited Partnership Axial-vortex jet drilling system and method
US5941461A (en) * 1997-09-29 1999-08-24 Vortexx Group Incorporated Nozzle assembly and method for enhancing fluid entrainment
US5992763A (en) * 1997-08-06 1999-11-30 Vortexx Group Incorporated Nozzle and method for enhancing fluid entrainment
US6142248A (en) * 1998-04-02 2000-11-07 Diamond Products International, Inc. Reduced erosion nozzle system and method for the use of drill bits to reduce erosion
WO2000066872A1 (en) * 1999-04-28 2000-11-09 Shell Internationale Research Maatschappij B.V. Abrasive jet drilling assembly
EP1616071A2 (en) * 2003-04-16 2006-01-18 Particle Drilling, Inc. Drill bit
US20070079993A1 (en) * 2003-10-29 2007-04-12 Shell Oil Company Fluid jet drilling tool
US20080017417A1 (en) * 2003-04-16 2008-01-24 Particle Drilling Technologies, Inc. Impact excavation system and method with suspension flow control
WO2008113844A1 (en) * 2007-03-22 2008-09-25 Shell Internationale Research Maatschappij B.V. Distance holder with helical slot
US20080230275A1 (en) * 2003-04-16 2008-09-25 Particle Drilling Technologies, Inc. Impact Excavation System And Method With Injection System
US20090126994A1 (en) * 2007-11-15 2009-05-21 Tibbitts Gordon A Method And System For Controlling Force In A Down-Hole Drilling Operation
US20090200084A1 (en) * 2004-07-22 2009-08-13 Particle Drilling Technologies, Inc. Injection System and Method
US20100155063A1 (en) * 2008-12-23 2010-06-24 Pdti Holdings, Llc Particle Drilling System Having Equivalent Circulating Density
US20100243240A1 (en) * 2005-11-18 2010-09-30 Blange Jan-Jette Device and method for feeding particles into a stream
US7987928B2 (en) 2007-10-09 2011-08-02 Pdti Holdings, Llc Injection system and method comprising an impactor motive device
US8037950B2 (en) 2008-02-01 2011-10-18 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
US8113300B2 (en) 2004-07-22 2012-02-14 Pdti Holdings, Llc Impact excavation system and method using a drill bit with junk slots
US8342265B2 (en) 2003-04-16 2013-01-01 Pdti Holdings, Llc Shot blocking using drilling mud
US8485279B2 (en) 2009-04-08 2013-07-16 Pdti Holdings, Llc Impactor excavation system having a drill bit discharging in a cross-over pattern
CN103835653A (en) * 2014-03-25 2014-06-04 中国石油大学(北京) Self-propelled rock debris grinding material straight-spinning jet mixing flow drill bit

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US3583503A (en) * 1969-03-12 1971-06-08 Lawrence Mfg Co Mounting head assembly
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Cited By (53)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4262757A (en) * 1978-08-04 1981-04-21 Hydronautics, Incorporated Cavitating liquid jet assisted drill bit and method for deep-hole drilling
US4334585A (en) * 1980-07-14 1982-06-15 Smith International, Inc. Insert retention and cooling apparatus for drag bits
FR2566832A1 (en) * 1984-06-27 1986-01-03 Inst Francais Du Petrole METHOD AND IMPROVEMENT TO DRILLING TOOLS FOR HIGH EFFICIENCY IN CLEANING THE SIZE FRONT
FR2566833A1 (en) * 1984-06-27 1986-01-03 Inst Francais Du Petrole METHOD AND IMPROVEMENT TO DRILLING TOOLS HAVING WATER PASSAGES ENABLING GREAT EFFICIENCY IN CLEANING THE SIZE FRONT
EP0169110A1 (en) * 1984-06-27 1986-01-22 Institut Français du Pétrole Drilling tools with water passages for a highly efficient cleaning of the work surface
EP0170548A1 (en) * 1984-06-27 1986-02-05 Institut Français du Pétrole Drilling tools having a high cleaning efficiency at the work surface
US4768709A (en) * 1986-10-29 1988-09-06 Fluidyne Corporation Process and apparatus for generating particulate containing fluid jets
US4892159A (en) * 1988-11-29 1990-01-09 Exxon Production Research Company Kerf-cutting apparatus and method for improved drilling rates
US5291957A (en) * 1990-09-04 1994-03-08 Ccore Technology And Licensing, Ltd. Method and apparatus for jet cutting
US5199512A (en) * 1990-09-04 1993-04-06 Ccore Technology And Licensing, Ltd. Method of an apparatus for jet cutting
US5542486A (en) * 1990-09-04 1996-08-06 Ccore Technology & Licensing Limited Method of and apparatus for single plenum jet cutting
US5145017A (en) * 1991-01-07 1992-09-08 Exxon Production Research Company Kerf-cutting apparatus for increased drilling rates
US5291956A (en) * 1992-04-15 1994-03-08 Union Oil Company Of California Coiled tubing drilling apparatus and method
US5469926A (en) * 1994-04-22 1995-11-28 Bor-Mor, Inc. Directional boring drill bit blade
US5595252A (en) * 1994-07-28 1997-01-21 Flowdril Corporation Fixed-cutter drill bit assembly and method
US5862871A (en) * 1996-02-20 1999-01-26 Ccore Technology & Licensing Limited, A Texas Limited Partnership Axial-vortex jet drilling system and method
US5992763A (en) * 1997-08-06 1999-11-30 Vortexx Group Incorporated Nozzle and method for enhancing fluid entrainment
US5941461A (en) * 1997-09-29 1999-08-24 Vortexx Group Incorporated Nozzle assembly and method for enhancing fluid entrainment
US6142248A (en) * 1998-04-02 2000-11-07 Diamond Products International, Inc. Reduced erosion nozzle system and method for the use of drill bits to reduce erosion
WO2000066872A1 (en) * 1999-04-28 2000-11-09 Shell Internationale Research Maatschappij B.V. Abrasive jet drilling assembly
US6510907B1 (en) 1999-04-28 2003-01-28 Shell Oil Company Abrasive jet drilling assembly
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
US20080017417A1 (en) * 2003-04-16 2008-01-24 Particle Drilling Technologies, Inc. Impact excavation system and method with suspension flow control
US20080230275A1 (en) * 2003-04-16 2008-09-25 Particle Drilling Technologies, Inc. Impact Excavation System And Method With Injection System
EP1616071A2 (en) * 2003-04-16 2006-01-18 Particle Drilling, Inc. Drill bit
US7909116B2 (en) 2003-04-16 2011-03-22 Pdti Holdings, Llc Impact excavation system and method with improved nozzle
US8162079B2 (en) 2003-04-16 2012-04-24 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
US7757786B2 (en) 2003-04-16 2010-07-20 Pdti Holdings, Llc Impact excavation system and method with injection system
US7419014B2 (en) 2003-10-29 2008-09-02 Shell Oil Company Fluid jet drilling tool
US20070079993A1 (en) * 2003-10-29 2007-04-12 Shell Oil Company Fluid jet drilling tool
US7997355B2 (en) 2004-07-22 2011-08-16 Pdti Holdings, Llc Apparatus for injecting impactors into a fluid stream using a screw extruder
US8113300B2 (en) 2004-07-22 2012-02-14 Pdti Holdings, Llc Impact excavation system and method using a drill bit with junk slots
US20090200084A1 (en) * 2004-07-22 2009-08-13 Particle Drilling Technologies, Inc. Injection System and Method
US20100243240A1 (en) * 2005-11-18 2010-09-30 Blange Jan-Jette Device and method for feeding particles into a stream
US8087480B2 (en) 2005-11-18 2012-01-03 Shell Oil Company Device and method for feeding particles into a stream
WO2008113844A1 (en) * 2007-03-22 2008-09-25 Shell Internationale Research Maatschappij B.V. Distance holder with helical slot
US8256533B2 (en) 2007-03-22 2012-09-04 Shell Oil Company Distance holder with helical slot
CN101641491B (en) * 2007-03-22 2013-03-20 国际壳牌研究有限公司 Distance holder with helical slot
AU2008228174B2 (en) * 2007-03-22 2011-04-14 Shell Internationale Research Maatschappij B.V. Distance holder with helical slot
US20100108389A1 (en) * 2007-03-22 2010-05-06 Blange Jan-Jette Distance holder with helical slot
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
US20090126994A1 (en) * 2007-11-15 2009-05-21 Tibbitts Gordon A Method And System For Controlling Force In A Down-Hole Drilling Operation
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
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
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
US8037950B2 (en) 2008-02-01 2011-10-18 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
US20100155063A1 (en) * 2008-12-23 2010-06-24 Pdti Holdings, Llc Particle Drilling System Having Equivalent Circulating Density
US8485279B2 (en) 2009-04-08 2013-07-16 Pdti Holdings, Llc Impactor excavation system having a drill bit discharging in a cross-over pattern
CN103835653A (en) * 2014-03-25 2014-06-04 中国石油大学(北京) Self-propelled rock debris grinding material straight-spinning jet mixing flow drill bit
CN103835653B (en) * 2014-03-25 2016-03-02 中国石油大学(北京) Self-advancing type landwaste abrasive material direct rotary mixing jet drill bit

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CA986088A (en) 1976-03-23

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