US3363706A - Bit with extended jet nozzles - Google Patents
Bit with extended jet nozzles Download PDFInfo
- Publication number
- US3363706A US3363706A US473358A US47335865A US3363706A US 3363706 A US3363706 A US 3363706A US 473358 A US473358 A US 473358A US 47335865 A US47335865 A US 47335865A US 3363706 A US3363706 A US 3363706A
- Authority
- US
- United States
- Prior art keywords
- bit
- elements
- nozzles
- drilling
- wear
- 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
Links
- 238000005553 drilling Methods 0.000 description 37
- 238000005520 cutting process Methods 0.000 description 30
- 230000001681 protective effect Effects 0.000 description 15
- 239000012530 fluid Substances 0.000 description 10
- 239000000463 material Substances 0.000 description 10
- 238000005552 hardfacing Methods 0.000 description 5
- 238000012360 testing method Methods 0.000 description 4
- 238000004891 communication Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000035515 penetration Effects 0.000 description 3
- 238000005219 brazing Methods 0.000 description 2
- 235000013339 cereals Nutrition 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 239000010432 diamond Substances 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000003208 petroleum Substances 0.000 description 2
- 239000011435 rock Substances 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 235000013312 flour Nutrition 0.000 description 1
- 238000005755 formation reaction Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 239000000565 sealant Substances 0.000 description 1
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
- E21B10/08—Roller bits
- E21B10/18—Roller 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
- E21B10/50—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of roller type
Definitions
- FIG. 1 A first figure.
- the invention relates to a rotary drilling bit with rotary cutting elements suitable to disintegrate rock material of underground formations, and provided with jet nozzles which are suitable to direct high velocity jets of drilling fluid to the bottom of a hole being drilled, so as to erode the hole bottom, to remove the cuttings therefrom and at the same time to clean and cool the cutting elements.
- These nozzles are preferably made of a wearresisting material since the driling fluid flowing therethrough usually has abrasive properties.
- the present invention relates to a rotary drilling bit of the above construction, in Which the jet nozzles are of the so-called extended type.
- the extended type nozzles are carried at the lower end of tubular elements extending in a downward direction from the bit body and communicating with the interior thereof. Each tubular element protrudes between a 'pair of adjacent rotary cutting elements.
- Another solution would be to use extended jet nozzles of shorter length, which nozzles would have their lower ends at a level relative to the rotary cutting elements where a suiiicient space is available for allowing the use of the required reinforcements.
- This solution would, however, decrease the drilling penetration rate since the distance between the discharge of each nozzle and the borehole bottom would have been increased which would unfavorably affect the interaction of the bit teeth and the hole bottom.
- the present invention now provides a solution for the existing problem, whereby damaging of the lower ends of the extended jet nozzles is prevented without influencing the drilling penetration rate.
- a rotary drilling bit comprises a bit body, legs extending from said body in a downward direction, bearing members on said legs, rotary cutting elements rotatably carried by the bearing members, tubular elements carried by the body, each tubular element communicating at one end thereof with the interior of the bit body and carrying at the other end thereof a nozzle, and protruding in a downward direction between a pair of adjacent cutting elements, each tubular element being provided, except at the lower end thereof, with a wear-resisting cover protecting at least that part of the tubular element facing the exterior of the drilling bit.
- the tubular element may be a pipe or tube.
- the tubular element may be a body through which a channel passes.
- the wear-resisting cover may have a U-shaped horizontal cross-section and may, in one embodiment, be separate from the tubular element. In another embodiof the tubular element.
- the radius of the outer wall of each cover is at most equal to the radius of the outermost parts of the cutting elements, and preferably the difference between these radii is at most 4; inch.
- the radius of the outer wall of each cover is preferably at least inch greater than the radius of the outermost parts of the lower ends of the tubular elements.
- FIGURE 1 shows by way of example a perspective view of a rotary drilling bit according to the invention with a sector cut away so as to show one of the extended nozzles in longitudinal section;
- FIGURE 2 shows (on a scale smaller than FIGURE 1) schematically a cross-section taken over line 22 in FIG. 1, indicating at which part of the drilling bit the sector has been cut away, as well as the direction (arrow I) in which the view shown in FIG. 1 has been taken; and
- FIGURES 3-6 are cross-sections of conduit tubes provided with protection covers of four diiferent constructions, all according to the invention.
- the rotary drilling bit as shown in the drawing comprises a bit body 1 which is provided at the upper side thereof wtih a hollow shank 2, in the outer wall of which is formed a screw thread 3.
- the interior 4 of the bit body l communicates with a conduit 5 formed within the shank 2.
- each leg 6 forms part of the bit body 1 and extend in a downward direction.
- each leg 6 is provided with hearing means for rotatably supporting a conical cutting element 7, which element is provided with teeth or other cutting 3,3 3 members.
- the central axis of each element intersects (or passes at a close distance to) the central axis of the rotary drilling bit. Only two of the three rotary cutting elements 7 have been shown in FIG. 1.
- each nozzle 8 consists of a tubular element or conduit 9 connected to the bit body 1 and having its interior in communication with the interior 4 of the body 1.
- the tubular elements 9 may form a single entity with the body 1 or, if the body is composed of three identical parts each including a leg 6, each part may form a single entity with a tubular element 9.
- each tubular element 9 is formed by a curved conduit or tube which at the upper end thereof passes through a bore formed in the bit body 1 along a downwardly diverging axis, and is connected thereto in a suitable manner, e.g., by welding.
- the lower end of each tubular element 9 is substantially vertical and carries a jet-forming nozzle 10 which is preferably made of a Wear-resisting material and may be connected to the element 9 in a manner known per se, e.g., by means of a snap-ring or brazing, using a suitable seal, e.g., rings or plastic sealants (not shown).
- a protective cover 11 is placed over the greater part of the tubular member 9, with the exception of the lower end thereof.
- the cover 11 and the tubular element 9 consist of separate parts.
- the cover 11 which consists of wear-resisting material, has a U-shaped horizontal cross-section and is connected to the bit body 1 in a suitable manner, e.g., by welds, such as 13. If desired, the cover 11 and the tube or conduit 9 may be connected by welds (such as 14), which are arranged where the cover 11 forms an angle to the tube 9.
- the cover does not need to consist of wear-resisting material for the total volume thereof.
- the cover lllla may be formed by a body 15 (FIG. 3) provided at the exterior surface thereof with a wear-resisting layer 16, such as a hard facing of large sized grains of tungsten carbide, hard metal and/or diamonds, which is applied to the outside of the bit.
- the open channel 17 of this cover is directed toward the central axis of the bit.
- the wear-resisting protective cover according to the invention is not formed separately from the tubular member, but is formed by applying and bonding a Wear-resisting layer 18 (FIG. 4) to the outer surface of the tubular member 9a.
- This layer 18 may be a hard facing of large sized grains of tungsten carbide, hard metal or diamonds.
- the wear-resisting protective cover according to the invention does not need to show a continuous surface.
- the cover may be formed of separate inserts 19 (FIG. of wear-resistant material, which inserts are fixed to a cover body 20, preferably U-shaped, at close distances from each other, e.g., by suitable locking means, welding or brazing.
- the inserts 19 may be of various cross-section, for example, they may be elongated in the direction of the axis of the drilling bit, or consist of pins having their axes substantially normal to the outer surface of the cover body 20.
- only two wear-resistance parts or inserts 21 of elongated shape are used (FIG. 6), which are fixed to the cover body 22 in such a way that they are substantially parallel to the axis of the drilling bit.
- the bodies (FIG. 3), 9a (FIG. 4-), (FIG. 5) and 22 (FIG. 6), respectively, on which they are mounted, are preferably of a ductile material.
- wear-resisting parts similar to inserts 19 (FIG. 5) and 21 (FIG. 6) may be directly mounted on the tubular element 9a, shown in FIG. 4, in place of layer 18.
- the cover 11 has a U-shaped cross-section, and is situated around the tube or conduit 9 (FIG. 1).
- This arrangement is preferred when adapting rotary drilling bits designed for jet nozzles arranged in openings of the bit body for the application of extended jet nozzles and protective covers according to the invention.
- a rotary drilling bit according to the invention, is provided with tubular elements formed by bodies having a channel passing therethrough (e.g., FIG. 4) rather than simple tubes
- the protective cover is preferably formed by a hard facing arranged at the outer side of each tubular element. These bodies may be welded to the bit body or form an integral part thereof.
- the radius of the outer wall of the covers is at least A inch greater than the radius of the outermost parts of the lower end of the tubular elements 9.
- the radius of the outer wall of the covers is at most equal but preferably smaller than the outer radius of the outermost parts of the cutting elements 7.
- the difference between these two radii depends on the extent to which play in the bearing members of the cutting elements, as a result of wear, is considered acceptable before replacing the bit with a new one.
- this difference is in the order of inch and not greater than 4; inch.
- a cover may extend over the lower part of a tubular element 9, it has been found from field tests with a drilling bit having covers protecting only the upper part of the elements 9, that this is sufiicient for preventing damage to the lower ends thereof. Moreover, such extension of the covers in a downward direction is often not feasible in view of the limited space available between the cutting elements 7, or, if done, is at the cost of the cross-section of the conduit 9, which then will wear out rapidly due to the abrasivity of the drilling fluid passing therethrough at high velocity.
- the covers are U-shaped, it is necessary that the area remaining between the outer walls of the legs of the U-shaped covers and the side walls of the legs 6 be large enough to allow the passage of drilling fluid, laden with cuttings, in an upward direction.
- channels may be provided through the legs 6, which commun cate with the space between the bit body and the cutting elements '7 at one end thereof, and at the other end, with the space above the legs 6.
- the invention is especially applicable to drilling bits having an outer diameter which is 6 inches or larger.
- bits larger than 8 inches, in particular when larger than 10 inches balling-up of the cutting elements during the drilling process often occurs.
- an extra nozzle, centrally arranged with respect to the bit body, is provided for combating this phenomenon which consists of the sticking of rock flour to the cutting elements thereby reducing the cutting action of the bit on the bottom of the hole being drilled.
- the lowest parts of the nozzles 8 should not be more than 1 inch above the level of the root of the heel teeth at the gauge side so as not to weaken unduly the effect of the jets on the bottom of the hole being drilled.
- the lowest part of the nozzles 8 may either be formed by the lowest part of the tubular members or by the lowest part of the nozzles 10, provided that these nozzles 10 extend beyond the tubular elements.
- the invention is also applicable to bits provided with jet nozzles having discharge openings, the axes of which are not normal to the hole bottom as indicated in FIG. 1.
- the axis of a tubular member and/or of a nozzle 10 and the central axis of the drilling bit do not need to be in a common plane.
- Such slanted arrangement of the nozzles 8 will combat bit balling of the cutting elements 7.
- a rotary drilling bit for drilling wells of the type employed in petroleum explorat'on and production which comprises:
- conduit means carried by the bit body in communication with the fluid cavity and extending downwardly substantially between the bases of adjacent conical elements below said bit body to a level of substantially one inch above the lowermost level of said root surface;
- substantially hard-facing wear-resisting protective cover means disposed on at least a portion of the outer surfaces of the nozzles exterior of the central axis of the bit body forming a protective cover for each said conduit means.
- a three-cone rotary drilling bit for drilling Wells of the type employed in petroleum exploration and production which comprises:
- conduit means carried by the bit body in communication with the fluid cavity and extending downwardly substantially between the bases of each two adjacent conical elements below said bit body to a level of substantially one inch above the lowermost level of said root surface;
- a drilling bit as defined by claim 4 wherein said protective cover means comprises:
- conduit means and protective cover means comprise:
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)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB539965A GB1049843A (en) | 1965-02-08 | 1965-02-08 | Rotary drilling bit |
GB3031965A GB1061090A (en) | 1965-07-16 | 1965-07-16 | Rotary drilling bit |
Publications (1)
Publication Number | Publication Date |
---|---|
US3363706A true US3363706A (en) | 1968-01-16 |
Family
ID=26239864
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US473358A Expired - Lifetime US3363706A (en) | 1965-02-08 | 1965-07-20 | Bit with extended jet nozzles |
Country Status (3)
Country | Link |
---|---|
US (1) | US3363706A (de) |
DE (1) | DE1232533B (de) |
NL (1) | NL6601551A (de) |
Cited By (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3509952A (en) * | 1968-12-11 | 1970-05-05 | Hughes Tool Co | Passageway extension for drilling tools |
US3897836A (en) * | 1973-10-18 | 1975-08-05 | Exotech | Apparatus for boring through earth formations |
US4077482A (en) * | 1976-09-27 | 1978-03-07 | Rolen Arsenievich Ioannesian | Three cone rock bit |
US4126194A (en) * | 1977-07-11 | 1978-11-21 | Smith International, Inc. | Rock bit with extended pickup tube |
US4189014A (en) * | 1978-08-14 | 1980-02-19 | Smith International, Inc. | Enhanced cross-flow with two jet drilling |
EP0040846A2 (de) * | 1980-05-27 | 1981-12-02 | Eduardo Barnetche Gonzalez | Körper und Düse zum Steigern des Durchflusses einer Bohrflüssigkeit in einem Drehbohrmeissel |
US4495840A (en) * | 1983-07-15 | 1985-01-29 | Reed Rock Bit Company | Bit breaker |
US4565252A (en) * | 1984-03-08 | 1986-01-21 | Lor, Inc. | Borehole operating tool with fluid circulation through arms |
US4623027A (en) * | 1985-06-17 | 1986-11-18 | Edward Vezirian | Unsegmented rotary rock bit structure and hydraulic fitting |
US4687067A (en) * | 1986-05-01 | 1987-08-18 | Smith International, Inc. | Crossflow rotary cone rock bit with extended nozzles |
US4759415A (en) * | 1986-01-31 | 1988-07-26 | Hughes Tool Company-Usa | Rock bit with improved extended nozzle |
US4793740A (en) * | 1986-11-28 | 1988-12-27 | Foundation Constructors | Drilling system |
US4871037A (en) * | 1988-09-15 | 1989-10-03 | Amoco Corporation | Excavation apparatus, system and method |
US4958962A (en) * | 1989-06-28 | 1990-09-25 | Halliburton Company | Methods of modifying the structural integrity of subterranean earth situs |
US5072796A (en) * | 1989-05-19 | 1991-12-17 | University Of Petroleum, China | Boring bit |
US5396964A (en) * | 1992-10-01 | 1995-03-14 | Halliburton Company | Apparatus and method for processing soil in a subterranean earth situs |
FR2751371A1 (fr) | 1996-07-19 | 1998-01-23 | Baker Hughes Inc | Trepans de forage a cones rotatifs, comportant des structures de buses deviees |
US6098728A (en) * | 1998-03-27 | 2000-08-08 | Baker Hughes Incorporated | Rock bit nozzle arrangement |
US6311789B1 (en) * | 1998-07-17 | 2001-11-06 | Halliburton Energy Services, Inc. | Bit breakers, bits, systems, and methods with improved makeup/breakout engagement |
US20040238225A1 (en) * | 2000-04-12 | 2004-12-02 | Smith International, Inc. | Rockbit with attachable device for improved cone cleaning |
US20060054357A1 (en) * | 2004-09-10 | 2006-03-16 | Centala Prabhakaran K | Two-cone drill bit |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1922436A (en) * | 1931-05-04 | 1933-08-15 | Hughes Tool Co | Flushing device for well drills |
US1945258A (en) * | 1931-09-16 | 1934-01-30 | Chicago Pneumatic Tool Co | Earth boring apparatus |
US2634101A (en) * | 1949-07-08 | 1953-04-07 | Sloan Pearl | Apparatus for accelerating the removal of cuttings from the bottom of wells |
US3115200A (en) * | 1957-08-28 | 1963-12-24 | Reed Roller Bit Co | Drill bit nozzle assembly |
US3207241A (en) * | 1963-04-08 | 1965-09-21 | Smith Tool Co | Jet bits |
-
1965
- 1965-07-20 US US473358A patent/US3363706A/en not_active Expired - Lifetime
-
1966
- 1966-02-07 DE DES101875A patent/DE1232533B/de active Pending
- 1966-02-08 NL NL6601551A patent/NL6601551A/xx unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1922436A (en) * | 1931-05-04 | 1933-08-15 | Hughes Tool Co | Flushing device for well drills |
US1945258A (en) * | 1931-09-16 | 1934-01-30 | Chicago Pneumatic Tool Co | Earth boring apparatus |
US2634101A (en) * | 1949-07-08 | 1953-04-07 | Sloan Pearl | Apparatus for accelerating the removal of cuttings from the bottom of wells |
US3115200A (en) * | 1957-08-28 | 1963-12-24 | Reed Roller Bit Co | Drill bit nozzle assembly |
US3207241A (en) * | 1963-04-08 | 1965-09-21 | Smith Tool Co | Jet bits |
Cited By (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3509952A (en) * | 1968-12-11 | 1970-05-05 | Hughes Tool Co | Passageway extension for drilling tools |
US3897836A (en) * | 1973-10-18 | 1975-08-05 | Exotech | Apparatus for boring through earth formations |
US4077482A (en) * | 1976-09-27 | 1978-03-07 | Rolen Arsenievich Ioannesian | Three cone rock bit |
US4126194A (en) * | 1977-07-11 | 1978-11-21 | Smith International, Inc. | Rock bit with extended pickup tube |
US4189014A (en) * | 1978-08-14 | 1980-02-19 | Smith International, Inc. | Enhanced cross-flow with two jet drilling |
EP0040846A2 (de) * | 1980-05-27 | 1981-12-02 | Eduardo Barnetche Gonzalez | Körper und Düse zum Steigern des Durchflusses einer Bohrflüssigkeit in einem Drehbohrmeissel |
EP0040846A3 (en) * | 1980-05-27 | 1982-07-07 | Eduardo Barnetche Gonzalez | A body structure and nozzle for enhancing the flow of drilling fluid in a rotary drill bit |
US4495840A (en) * | 1983-07-15 | 1985-01-29 | Reed Rock Bit Company | Bit breaker |
US4565252A (en) * | 1984-03-08 | 1986-01-21 | Lor, Inc. | Borehole operating tool with fluid circulation through arms |
US4623027A (en) * | 1985-06-17 | 1986-11-18 | Edward Vezirian | Unsegmented rotary rock bit structure and hydraulic fitting |
US4759415A (en) * | 1986-01-31 | 1988-07-26 | Hughes Tool Company-Usa | Rock bit with improved extended nozzle |
US4687067A (en) * | 1986-05-01 | 1987-08-18 | Smith International, Inc. | Crossflow rotary cone rock bit with extended nozzles |
US4793740A (en) * | 1986-11-28 | 1988-12-27 | Foundation Constructors | Drilling system |
US4871037A (en) * | 1988-09-15 | 1989-10-03 | Amoco Corporation | Excavation apparatus, system and method |
US5072796A (en) * | 1989-05-19 | 1991-12-17 | University Of Petroleum, China | Boring bit |
US4958962A (en) * | 1989-06-28 | 1990-09-25 | Halliburton Company | Methods of modifying the structural integrity of subterranean earth situs |
US5396964A (en) * | 1992-10-01 | 1995-03-14 | Halliburton Company | Apparatus and method for processing soil in a subterranean earth situs |
FR2751371A1 (fr) | 1996-07-19 | 1998-01-23 | Baker Hughes Inc | Trepans de forage a cones rotatifs, comportant des structures de buses deviees |
BE1013515A5 (fr) | 1998-03-27 | 2002-03-05 | Bakers Hughes Inc | Agencement de trepan tricone. |
US6098728A (en) * | 1998-03-27 | 2000-08-08 | Baker Hughes Incorporated | Rock bit nozzle arrangement |
US6311789B1 (en) * | 1998-07-17 | 2001-11-06 | Halliburton Energy Services, Inc. | Bit breakers, bits, systems, and methods with improved makeup/breakout engagement |
US20040238225A1 (en) * | 2000-04-12 | 2004-12-02 | Smith International, Inc. | Rockbit with attachable device for improved cone cleaning |
US7703354B2 (en) | 2000-04-12 | 2010-04-27 | Smith International, Inc. | Method of forming a nozzle retention body |
US20060054357A1 (en) * | 2004-09-10 | 2006-03-16 | Centala Prabhakaran K | Two-cone drill bit |
US7681670B2 (en) * | 2004-09-10 | 2010-03-23 | Smith International, Inc. | Two-cone drill bit |
US20100132510A1 (en) * | 2004-09-10 | 2010-06-03 | Smith International, Inc. | Two-cone drill bit |
Also Published As
Publication number | Publication date |
---|---|
DE1232533B (de) | 1967-01-19 |
NL6601551A (de) | 1966-08-09 |
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