US3047313A - Weighted drill collar - Google Patents

Weighted drill collar Download PDF

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US3047313A
US3047313A US148268A US14826861A US3047313A US 3047313 A US3047313 A US 3047313A US 148268 A US148268 A US 148268A US 14826861 A US14826861 A US 14826861A US 3047313 A US3047313 A US 3047313A
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drill collar
drill
collar
present
wall members
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US148268A
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George H Bruce
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Jersey Production Research Co
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Jersey Production Research Co
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/16—Drill collars

Definitions

  • the present invention is directed to an improved drill collar. More specifically, the invention is directed to an improved drill collar which increases the weight of a drill string in which it is arranged. In its more specific aspects, the invention is concerned with a heavy drill collar which utilizes the pendulum effect in preventing hole deviation in drilling wells with a drill string.
  • the present invention may be briefly described as a drill collar for use in a drill string which comprises inner and outer spaced-apart elongated wall members. Arranged between the wall members and bondedly attached thereto are cellular reinforcing means which provide strength for the drill collar. The inner of the wall members provides an unobstructed bore for passage of fluid and tools therethrough. Means are attached to each end of the wall members for connecting the drill collar threadedly into a drill string. In the cellular reinforcing means there is arranged in the cells thereof a weighting means such as a heavy metal or a derivative thereof having a specific gravity greater than 8.0.
  • a heavy drill collar is provided which utilizes the pendulum effect in drilling wells in a drill string having the drill collar therein.
  • FIGURE is an elevational view partly in section of a preferred embodiment.
  • the drill collar of the present invention is made up of a thin-walled outer tubular member 11 and a thin-walled inner tubular member 12. These tubes 11 and 1'2 are spaced apart and are separated by a cellular structure 13 which may be of a honeycomb type such as used in reinforcing the airfoils of high-performance aircraft. Honeycomb structure 13 is provided with passages into each cell and throughout the length of the drill collar generally indicating by the numeral 14 to allow a filler material to be placed in the honeycomb structure 13.
  • the outer tubular member is also suitably provided with means for introducing filler material into the cellular structure.
  • the outer tubular member 11 and the inner tubular member 12, forming the drill collar 14, have connecting means 15 and 16 attached to each end thereof for attaching the drill collar 14 into a drill string for use in drilling a well.
  • the connecting means 15 and 16 are provided with threads 17 and 18, respectively, for threadedly connecting the drill collar 14 into a drill string for use in drilling operations.
  • the connecting means 15 and 16 are provided with recesses 19, 20, 21, and 22 into which the wall members 11 and 12 fit such that the wall members .11 and 12 may be rigidly and fixedly attached to the connecting means 15 and 16.
  • the heavy metal employed as a filler in the honeycomb or cellular structure 13 is preferably lead, but other heavy metals such as mercury, tungsten, osmium, and uranium maybe used. Also the derivatives of these metals such as oxides and the like may be used such as the oxides of lead, mercury, tungsten and uranium. To illustrate the difference in weights of the several heavy metals as compared to iron or steel which usually makes up the drill collar, the specific gravity of iron is compared Cir "ice
  • alloys of lead may be used; woods metal, antimonial lead and plumbers solder may be employed. These alloys have specific gravities of 9.7, 11.0, and 9.4, respectively.
  • the device of the present invention is easily constructed and the tubular members :11 and 12 may suitably be flash welded to the connecting means 15 and 16.
  • a drill collar of five-inch outside diameter and two-inch inside diameter with a quarter-inch inner wall and three-eighths-inch outer wall and filled with lead will weigh about 70 pounds per foot when made of steel, which has a density of about 490 pounds per cubic foot.
  • Lead has a density of about 700 pounds per cubic foot.
  • collar made of steel alone weighs about 56 pounds per foot; thus the dense or heavy metal provides a 25 percent increase in the weight with no increase in diameter.
  • the cellular reinforcing means is necessarily formed of a high melting point metal which is substantially chemically inert to and is not attached by the heavy metal weighting means received in the cells in a liquid state.
  • a collar such as described herein is therefore easy to construct and is of substantially the same strength as the conventional drill collar, but is of greater weight than the conventional drill collar. Thus, the available weight per foot may be increased without increasing the drill collar diameter.
  • Drill collars such as in the present invention will be as strong and rigid as those currently in use which are usually formed by 'boring and turning operations from large forged steel billets. Thus, the present invention provides a drill collar which is heavier and is competitive in cost with the conventional drill collar.
  • the drill collars now used in drilling opera tions to provide weight to the drill bit and to prevent borehole deviation sometimes fail to achieve this end.
  • the drill collars, to prevent hole deviation, utilize the pendulum effect and to achieve this must be heavy and rigid.
  • the conventional drill collars made of thick walled pipe and manufactured by boring and turning a solid steel forging have weight and rigidity from the thickness of the wall. Since borehole diameters are limited, wall thickness of the conventional drill collar is also limited.
  • the present invention provides a means for adding additional weight to drill strings in drill collars where the diameter of the borehole is limited. Accordingly, the present invention is quite advantageous and useful in that providing additional weight and thus utilizing the pendulum effect, boreholes may be drilled straighter with less deviation than now is frequently encountered.
  • a drill collar for use in a drill string which comprises inner and outer spaced apart tubular wall members, cellular reinforcing means between and bondedly attached and secured at least to said wall members throughout the length thereof, said cellular reinforcing means forming a plurality of cells in and throughout the length and width of said space with passageways in said cellular reinforcing means into each cell, the inner of said wall members providing an unobstructed bore for passage of fluid, means attached to each end of said wall members for connecting said drill collar into a drill string, and metal weighting means having a specific gravity greater than 8.0 in and filling said cells whereby a heavy drill collar and a pendulum effect to said drill string are provided, said cellular reinforcing means being formed of a high melting point metal substantially chemically inert to and unattacked by said metal weighting means received into said cells in a liquid state.

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  • 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)

Description

July 31, 1962 cs. H. BRUCE WEIGHTED DRILL COLLAR Filed Oct. 27, 1961 INVENTOR. GEORGE H. BRUCE.
AFR
United States Patent 3,047,313 WEIGHTED DRILL COLLAR George H. Bruce, Houston, Tex., assignor, by mesne assignments, to Jersey Production Research Company, Tulsa, Okla., a corporation of Delaware Filed Oct. 27, 1961, Ser. No. 148,268 5 Claims. (Cl. 285-47) The present invention is directed to an improved drill collar. More specifically, the invention is directed to an improved drill collar which increases the weight of a drill string in which it is arranged. In its more specific aspects, the invention is concerned with a heavy drill collar which utilizes the pendulum effect in preventing hole deviation in drilling wells with a drill string.
This application is a continuation-in-part of Serial No. 850,869 entitled, Drill Collar, and filed November 4, 1959 for George H. Bruce, and now abandoned.
The present invention may be briefly described as a drill collar for use in a drill string which comprises inner and outer spaced-apart elongated wall members. Arranged between the wall members and bondedly attached thereto are cellular reinforcing means which provide strength for the drill collar. The inner of the wall members provides an unobstructed bore for passage of fluid and tools therethrough. Means are attached to each end of the wall members for connecting the drill collar threadedly into a drill string. In the cellular reinforcing means there is arranged in the cells thereof a weighting means such as a heavy metal or a derivative thereof having a specific gravity greater than 8.0. By virtue of the drill collar in accordance with the present invention, a heavy drill collar is provided which utilizes the pendulum effect in drilling wells in a drill string having the drill collar therein.
The present invention will be further described by reference to the drawing in which the single FIGURE is an elevational view partly in section of a preferred embodiment.
The drill collar of the present invention is made up of a thin-walled outer tubular member 11 and a thin-walled inner tubular member 12. These tubes 11 and 1'2 are spaced apart and are separated by a cellular structure 13 which may be of a honeycomb type such as used in reinforcing the airfoils of high-performance aircraft. Honeycomb structure 13 is provided with passages into each cell and throughout the length of the drill collar generally indicating by the numeral 14 to allow a filler material to be placed in the honeycomb structure 13. The outer tubular member is also suitably provided with means for introducing filler material into the cellular structure. The outer tubular member 11 and the inner tubular member 12, forming the drill collar 14, have connecting means 15 and 16 attached to each end thereof for attaching the drill collar 14 into a drill string for use in drilling a well. The connecting means 15 and 16 are provided with threads 17 and 18, respectively, for threadedly connecting the drill collar 14 into a drill string for use in drilling operations. The connecting means 15 and 16 are provided with recesses 19, 20, 21, and 22 into which the wall members 11 and 12 fit such that the wall members .11 and 12 may be rigidly and fixedly attached to the connecting means 15 and 16.
The heavy metal employed as a filler in the honeycomb or cellular structure 13 is preferably lead, but other heavy metals such as mercury, tungsten, osmium, and uranium maybe used. Also the derivatives of these metals such as oxides and the like may be used such as the oxides of lead, mercury, tungsten and uranium. To illustrate the difference in weights of the several heavy metals as compared to iron or steel which usually makes up the drill collar, the specific gravity of iron is compared Cir "ice
to the specific gravities of the several heavy metals in Table I.
Certain alloys may also be used as the filler in the present invention. For example, alloys of lead may be used; woods metal, antimonial lead and plumbers solder may be employed. These alloys have specific gravities of 9.7, 11.0, and 9.4, respectively.
The device of the present invention is easily constructed and the tubular members :11 and 12 may suitably be flash welded to the connecting means 15 and 16.
In order to illustrate the present invention, a drill collar of five-inch outside diameter and two-inch inside diameter with a quarter-inch inner wall and three-eighths-inch outer wall and filled with lead will weigh about 70 pounds per foot when made of steel, which has a density of about 490 pounds per cubic foot. Lead has a density of about 700 pounds per cubic foot. The same. collar made of steel alone weighs about 56 pounds per foot; thus the dense or heavy metal provides a 25 percent increase in the weight with no increase in diameter.
The employment of sandwich or cellular or honey comb type of structure has been well developed in many years and is well known to the art. It is apparent that the cellular reinforcing means is necessarily formed of a high melting point metal which is substantially chemically inert to and is not attached by the heavy metal weighting means received in the cells in a liquid state. A collar such as described herein is therefore easy to construct and is of substantially the same strength as the conventional drill collar, but is of greater weight than the conventional drill collar. Thus, the available weight per foot may be increased without increasing the drill collar diameter. Drill collars such as in the present invention will be as strong and rigid as those currently in use which are usually formed by 'boring and turning operations from large forged steel billets. Thus, the present invention provides a drill collar which is heavier and is competitive in cost with the conventional drill collar.
Moreover, the drill collars now used in drilling opera tions to provide weight to the drill bit and to prevent borehole deviation sometimes fail to achieve this end. The drill collars, to prevent hole deviation, utilize the pendulum effect and to achieve this must be heavy and rigid. The conventional drill collars made of thick walled pipe and manufactured by boring and turning a solid steel forging have weight and rigidity from the thickness of the wall. Since borehole diameters are limited, wall thickness of the conventional drill collar is also limited. The present invention provides a means for adding additional weight to drill strings in drill collars where the diameter of the borehole is limited. Accordingly, the present invention is quite advantageous and useful in that providing additional weight and thus utilizing the pendulum effect, boreholes may be drilled straighter with less deviation than now is frequently encountered.
While specific examples of the several heavy metals and oxides thereof have been given, these examples are by way of illustration and not by way of limitation since any heavy metal or material having a specific gravity greater than 8.0 may be used as the filler material.
The nature and objects of the present invention having been completely described and illustrated, what I wish to claim as new and useful and secure by Letters Patent is:
l. A drill collar for use in a drill string which comprises inner and outer spaced apart tubular wall members, cellular reinforcing means between and bondedly attached and secured at least to said wall members throughout the length thereof, said cellular reinforcing means forming a plurality of cells in and throughout the length and width of said space with passageways in said cellular reinforcing means into each cell, the inner of said wall members providing an unobstructed bore for passage of fluid, means attached to each end of said wall members for connecting said drill collar into a drill string, and metal weighting means having a specific gravity greater than 8.0 in and filling said cells whereby a heavy drill collar and a pendulum effect to said drill string are provided, said cellular reinforcing means being formed of a high melting point metal substantially chemically inert to and unattacked by said metal weighting means received into said cells in a liquid state.
2. A drill collar in accordance with claim 1 in which the metal Weighting means is lead.
3. A drill collar in accordance with claim 1 in which the metal weighting means is mercury.
4. A drill collar in accordance with claim 1 in which the metal weighting means is an alloy of lead.
5. A drill collar in accordance with claim 1 in which the cellular reinforcing means provides a honeycomb structure.
References Cited in the file of this patent UNITED STATES PATENTS 1,712,803 Wood May 14, 1929 1,746,132 Stockes Feb. 4, 1930 2,126,075 Wright Aug. 9, 1938 2,814,462 DeJarnett Nov. 26, 1957
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Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3195927A (en) * 1962-04-04 1965-07-20 Flexweight Drill Pipe Co Inc Weight pipe
US3232638A (en) * 1962-11-26 1966-02-01 American Mach & Foundry Prestressed tubes and rods
US3261414A (en) * 1965-05-12 1966-07-19 Reed Roller Bit Co Drill collar
DE1296899B (en) * 1962-11-13 1969-06-04 Armco Steel Corp Double-walled plastic pipe with webs and / or a porous filler in the space between the walls
US3706348A (en) * 1971-12-06 1972-12-19 Shell Oil Co Well deviation control system
US4146060A (en) * 1977-07-25 1979-03-27 Smith International, Inc. Drill pipe wear belt assembly
US4221549A (en) * 1976-10-12 1980-09-09 United States Steel Corporation Inertia bar for sucker rods
US4278138A (en) * 1980-01-21 1981-07-14 Christensen, Inc. Composite heavy metal drill collar
US4310059A (en) * 1980-01-21 1982-01-12 Christensen, Inc. Composite heavy metal drill collar
US4674171A (en) * 1984-04-20 1987-06-23 Lor, Inc. Heavy wall drill pipe and method of manufacture of heavy wall drill pipe
US4771811A (en) * 1984-04-20 1988-09-20 Lor, Inc. Heavy wall drill pipe and method of manufacture of heavy wall drill pipe
US4872519A (en) * 1988-01-25 1989-10-10 Eastman Christensen Company Drill string drill collars
US4881605A (en) * 1988-09-15 1989-11-21 Amoco Corporation Stabilizing and drilling apparatus and method
US5174395A (en) * 1991-09-13 1992-12-29 Inco Limited In-the-hole drill inner tube rod
US5713423A (en) * 1992-07-24 1998-02-03 The Charles Machine Works, Inc. Drill pipe
US5868437A (en) * 1995-07-17 1999-02-09 Teague; Anthony Composite pipe structure
US5964294A (en) * 1996-12-04 1999-10-12 Schlumberger Technology Corporation Apparatus and method for orienting a downhole tool in a horizontal or deviated well
US20040149492A1 (en) * 2003-01-27 2004-08-05 Taylor Bruce L. Drilling assembly and method
US7726392B1 (en) 2008-03-26 2010-06-01 Robertson Michael C Removal of downhole drill collar from well bore
US20120037367A1 (en) * 2010-08-13 2012-02-16 Benton Frederick Baugh Shearable drill pipe method
US8235102B1 (en) 2008-03-26 2012-08-07 Robertson Intellectual Properties, LLC Consumable downhole tool
US8327926B2 (en) 2008-03-26 2012-12-11 Robertson Intellectual Properties, LLC Method for removing a consumable downhole tool
US8967675B2 (en) * 2012-08-24 2015-03-03 Vetco Gray Inc. Elliptical undercut shoulder for specialty pipe connections
US20180073304A1 (en) * 2016-09-14 2018-03-15 Mitchell Z. Dziekonski Shearable tubular system and method
US20180245406A1 (en) * 2017-02-27 2018-08-30 Mitchell Z. Dziekonski Shearable riser system and method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1712803A (en) * 1927-02-23 1929-05-14 Wood Charles Edward Float drill pipe
US1746132A (en) * 1925-08-01 1930-02-04 Stokes John Creighton Drill pipe
US2126075A (en) * 1936-08-24 1938-08-09 Martha H Wright Drill collar
US2814462A (en) * 1954-05-26 1957-11-26 Paul A Medearis Fluid packed drill collar

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1746132A (en) * 1925-08-01 1930-02-04 Stokes John Creighton Drill pipe
US1712803A (en) * 1927-02-23 1929-05-14 Wood Charles Edward Float drill pipe
US2126075A (en) * 1936-08-24 1938-08-09 Martha H Wright Drill collar
US2814462A (en) * 1954-05-26 1957-11-26 Paul A Medearis Fluid packed drill collar

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3195927A (en) * 1962-04-04 1965-07-20 Flexweight Drill Pipe Co Inc Weight pipe
DE1296899B (en) * 1962-11-13 1969-06-04 Armco Steel Corp Double-walled plastic pipe with webs and / or a porous filler in the space between the walls
US3232638A (en) * 1962-11-26 1966-02-01 American Mach & Foundry Prestressed tubes and rods
US3261414A (en) * 1965-05-12 1966-07-19 Reed Roller Bit Co Drill collar
US3706348A (en) * 1971-12-06 1972-12-19 Shell Oil Co Well deviation control system
US4221549A (en) * 1976-10-12 1980-09-09 United States Steel Corporation Inertia bar for sucker rods
US4146060A (en) * 1977-07-25 1979-03-27 Smith International, Inc. Drill pipe wear belt assembly
US4310059A (en) * 1980-01-21 1982-01-12 Christensen, Inc. Composite heavy metal drill collar
US4278138A (en) * 1980-01-21 1981-07-14 Christensen, Inc. Composite heavy metal drill collar
US4674171A (en) * 1984-04-20 1987-06-23 Lor, Inc. Heavy wall drill pipe and method of manufacture of heavy wall drill pipe
US4771811A (en) * 1984-04-20 1988-09-20 Lor, Inc. Heavy wall drill pipe and method of manufacture of heavy wall drill pipe
US4872519A (en) * 1988-01-25 1989-10-10 Eastman Christensen Company Drill string drill collars
US4881605A (en) * 1988-09-15 1989-11-21 Amoco Corporation Stabilizing and drilling apparatus and method
US5174395A (en) * 1991-09-13 1992-12-29 Inco Limited In-the-hole drill inner tube rod
US5713423A (en) * 1992-07-24 1998-02-03 The Charles Machine Works, Inc. Drill pipe
US5868437A (en) * 1995-07-17 1999-02-09 Teague; Anthony Composite pipe structure
US5964294A (en) * 1996-12-04 1999-10-12 Schlumberger Technology Corporation Apparatus and method for orienting a downhole tool in a horizontal or deviated well
US7059429B2 (en) * 2003-01-27 2006-06-13 Strataloc Technology Products, Llc Drilling assembly and method
US20070039757A1 (en) * 2003-01-27 2007-02-22 Nichols Richard A Tension/collar/reamer assemblies and methods
US7353888B2 (en) 2003-01-27 2008-04-08 Strataloc Technology Products Llc Tension/collar/reamer assemblies and methods
US20080142266A1 (en) * 2003-01-27 2008-06-19 Nichols Richard A Tension/collar/reamer assemblies and methods
US7730971B2 (en) 2003-01-27 2010-06-08 Strataloc Technology Products Llc Tension/collar/reamer assemblies and methods
US20100230167A1 (en) * 2003-01-27 2010-09-16 Strataloc Technology Products Llc Tension/collar/reamer assemblies and methods
US7987926B2 (en) 2003-01-27 2011-08-02 Strataloc Technology Products Llc Tension/collar/reamer assemblies and methods
US20040149492A1 (en) * 2003-01-27 2004-08-05 Taylor Bruce L. Drilling assembly and method
US8327926B2 (en) 2008-03-26 2012-12-11 Robertson Intellectual Properties, LLC Method for removing a consumable downhole tool
US7726392B1 (en) 2008-03-26 2010-06-01 Robertson Michael C Removal of downhole drill collar from well bore
US20100218952A1 (en) * 2008-03-26 2010-09-02 Robertson Michael C Method and apparatus to remove a downhole drill collar from a well bore
US7997332B2 (en) 2008-03-26 2011-08-16 Robertson Intellectual Properties, LLC Method and apparatus to remove a downhole drill collar from a well bore
US8235102B1 (en) 2008-03-26 2012-08-07 Robertson Intellectual Properties, LLC Consumable downhole tool
US20120037367A1 (en) * 2010-08-13 2012-02-16 Benton Frederick Baugh Shearable drill pipe method
US8584775B2 (en) * 2010-08-13 2013-11-19 Benton Frederick Baugh Shearable drill pipe method and apparatus
US8746372B2 (en) 2010-08-13 2014-06-10 Benton Frederick Baugh Shearable drill pipe and method
US8967675B2 (en) * 2012-08-24 2015-03-03 Vetco Gray Inc. Elliptical undercut shoulder for specialty pipe connections
US20180073304A1 (en) * 2016-09-14 2018-03-15 Mitchell Z. Dziekonski Shearable tubular system and method
US10480255B2 (en) * 2016-09-14 2019-11-19 Mitchell Z. Dziekonski Shearable tubular system and method
US20180245406A1 (en) * 2017-02-27 2018-08-30 Mitchell Z. Dziekonski Shearable riser system and method
US10914125B2 (en) * 2017-02-27 2021-02-09 Mitchell Z. Dziekonski Shearable riser system and method
US11280139B2 (en) 2017-02-27 2022-03-22 Mitchell Z. Dziekonski Shearable riser system and method

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