WO1998009046A1 - A drill pipe - Google Patents

A drill pipe Download PDF

Info

Publication number
WO1998009046A1
WO1998009046A1 PCT/GB1997/002236 GB9702236W WO9809046A1 WO 1998009046 A1 WO1998009046 A1 WO 1998009046A1 GB 9702236 W GB9702236 W GB 9702236W WO 9809046 A1 WO9809046 A1 WO 9809046A1
Authority
WO
WIPO (PCT)
Prior art keywords
drill pipe
diameter
section
enlarged
spiral formation
Prior art date
Application number
PCT/GB1997/002236
Other languages
French (fr)
Inventor
William Russell Scott Aitken
Original Assignee
Schoeller Bleckmann Oilfield Equipment Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Schoeller Bleckmann Oilfield Equipment Limited filed Critical Schoeller Bleckmann Oilfield Equipment Limited
Priority to CA002263901A priority Critical patent/CA2263901A1/en
Priority to DE69712893T priority patent/DE69712893T2/en
Priority to EP97937683A priority patent/EP0922153B1/en
Priority to US09/242,573 priority patent/US6167917B1/en
Priority to AU40227/97A priority patent/AU725911B2/en
Priority to AT97937683T priority patent/ATE218181T1/en
Publication of WO1998009046A1 publication Critical patent/WO1998009046A1/en
Priority to NO990959A priority patent/NO990959D0/en

Links

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
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/10—Wear protectors; Centralising devices, e.g. stabilisers
    • 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
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/22—Rods or pipes with helical structure
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S138/00—Pipes and tubular conduits
    • Y10S138/11—Shape

Definitions

  • the invention relates to drill pipe and, in particular, drill pipe for use in drilling boreholes, such as oil and/or gas wells.
  • a drill pipe comprises a length of conduit having a first diameter, a first and a second end portion, each end portion having a second diameter greater than the first diameter, and an enlarged portion located between and spaced from the first and second end portions, the enlarged portion comprising a central section having a third diameter greater than the first diameter and the central section having a substantially smooth external surface, and two end sections, one end section at either end of the central section, which vary in diameter between the first and the third diameter, and one of the end sections having a spiral formation thereon.
  • the spiral formation is located between the central section and the upper end of the drill pipe.
  • the external surface of the central section is—a__substantially cylindrical surface. _
  • three of said enlarged portions may be provided on the drill pipe.
  • the other end section may comprise a curved surface which may be convex and is typically radiused.
  • the other end section may typically comprise a linearly sloping surface.
  • the spiral formations are deeper and/or wider adjacent the central section.
  • the end section in which the spiral formations are formed has a concave shape.
  • the end section in which the spiral formations are formed may comprise a curved surface which may be convex and is typically radiused.
  • Fig. 1 is a side view of a length of drill pipe; and Fig. 2 is a side view of a section of a length of drill pipe.
  • Fig. 1 shows a side view of a length of a drill pipe 1 which comprises a tube section 2 which has a first diameter and a first enlarged end portion 3 having a second diameter at the upper end which includes a threaded box connection 4, and a second enlarged end portion 5 which is the same diameter as the portion 3 at the lower end which has a threaded pin connection 6.
  • the threaded box connection 4 and threaded pin connection 6 permit the drill pipe 1 to be connected to other lengths of drill pipe (not shown) to form a drill string for drilling a borehole, such as an oil/or gas well.
  • the tube 2 also has an enlarged central portion 7 with a central cylindrical surface 8 which is parallel to the exterior walls of the tube 2 and the longitudinal axis of the drill pipe 1.
  • the cylindrical surface 8 is smooth and is connected to the tube 2 at its upper end by a concave surface 9 and to the lower portion of tube 2 by a convex surface 10.
  • Located in the concave surface 9 are a number of spiral formations 11 which are cut out of the concave surface 9.
  • the drill pipe 1 shown in Fig. 1 is truncated and the full length of drill pipe 1 would typically have three enlarged central portions 7 spaced along its length between the enlarged end portions 3, 5.
  • two of the enlarged central portions 7 have a spiral formation 11 formed in one direction around the circumference of the concave surface 9, and the third enlarged central portion 7 having a spiral formation 11 formed in the other direction.
  • hard banding may be applied to the enlarged portion 7, if desired.
  • An advantage of the drill pipe 1 is that the cylindrical surface 8 is smooth which helps prevent the enlarged section biting into the side walls of the bore hole during drilling.
  • the spiral formations 11 help to promote agitation of drill cuttings within the well to mitigate the problems of drill cuttings collecting on the lower side of the well.
  • the spiral formations 11 would be deeper and wider adjacent the cylindrical surface 8 than adjacent the tube 2.
  • the maximum diameter of the enlarged portion 7 is typically less than or equal to the diameter of the enlarged end portions 3, 5.
  • Fig.2 shows a second example of an enlarged central portion 15 which can be incorporated into a length of the drill pipe 1 shown in Fig. 1 in addition to, or instead of the enlarged central portion 7 of Fig. 1.
  • the enlarged central portion 15 of Fig. 2 has a similar central cylindrical surface 8 to that of Fig. 1.
  • the central cylindrical surface 8 of Fig. 2 is connected to the tube section 2 at its upper end by a convex and radiussed surface 17, into which are cut six spiral formations 19.
  • the central cylindrical surface 8 is connected at its lower end to the tube 2 by a linearly sloping section 21.
  • the invention has the advantage that a greater surface area of metal may be scooped away to form the spiral formations 19, which increases the efficiency of the invention by causing greater turbulence, in use.
  • each of the linearly sloping section 21, cylindrical surface 8 and the convex and radiussed section 17 is 9".
  • the diameter of the cylindrical surface 8 is 6V
  • the diameter of the cylindrical surface 8 is 8V .

Landscapes

  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Drilling Tools (AREA)
  • Surgical Instruments (AREA)
  • Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)

Abstract

A drill pipe (1) is described as having a length of conduit (2) having a first diameter, a first (3) and a second (5) end portion, where each end portion (3, 5) has a second diameter greater than the first diameter. An enlarged portion (7, 15) is located between and spaced from the first (3) and second (5) end portions, where the enlarged portion (7, 15) comprises a central section (8) which has a third diameter greater than the first diameter. The central section (8) has a substantially smooth external surface, and two end sections (9, 10; 17, 21), one end section (9, 10; 17, 21) at either end of the central section (8), which vary in diameter between the first and the third diameter. One of the end sections (9; 17) has a spiral formation (11; 19) thereon.

Description

"A Drill Pipe"
The invention relates to drill pipe and, in particular, drill pipe for use in drilling boreholes, such as oil and/or gas wells.
Modern drilling techniques in the exploration of oil and gas permit the drilling of boreholes which have a large angle of deviation from the vertical, and in some cases boreholes may be horizontal or close to the horizontal. Such boreholes are known as lateral wells. However, during drilling of a lateral well, the drill cuttings tend to accumulate on the lower side of the hole and it is difficult to flush the drill cuttings out of a lateral well with the normal drilling fluid flow between the drill string and the inside surface of the borehole.
Accordingly, in recent years proposals have been made for enhancing the agitation of the drill cuttings within lateral wells to help prevent accumulation of the drill cuttings on the lower side of the borehole.
Some of these proposals include forming upsets on the drill pipe and putting spiral formations on the surface of the upsets to agitate the drill cuttings in the lower section of the well as the drill pipe is rotated. However, this type of drill pipe has the disadvantage that it can tend to cut into the side wall of the bore hole as it rotates.
In accordance with present invention, a drill pipe comprises a length of conduit having a first diameter, a first and a second end portion, each end portion having a second diameter greater than the first diameter, and an enlarged portion located between and spaced from the first and second end portions, the enlarged portion comprising a central section having a third diameter greater than the first diameter and the central section having a substantially smooth external surface, and two end sections, one end section at either end of the central section, which vary in diameter between the first and the third diameter, and one of the end sections having a spiral formation thereon.
Preferably, the spiral formation is located between the central section and the upper end of the drill pipe.
Preferably, the external surface of the central section is—a__substantially cylindrical surface. _ Typically, three of said enlarged portions may be provided on the drill pipe.
Preferably, the other end section may comprise a curved surface which may be convex and is typically radiused.
Alternatively, the other end section may typically comprise a linearly sloping surface. Preferably, the spiral formations are deeper and/or wider adjacent the central section.
Preferably, the end section in which the spiral formations are formed has a concave shape.
Alternatively, the end section in which the spiral formations are formed may comprise a curved surface which may be convex and is typically radiused.
Examples of a drill pipe in accordance with the invention will now be described with reference to the accompanying drawings, in which: -
Fig. 1 is a side view of a length of drill pipe; and Fig. 2 is a side view of a section of a length of drill pipe.
Fig. 1 shows a side view of a length of a drill pipe 1 which comprises a tube section 2 which has a first diameter and a first enlarged end portion 3 having a second diameter at the upper end which includes a threaded box connection 4, and a second enlarged end portion 5 which is the same diameter as the portion 3 at the lower end which has a threaded pin connection 6. The threaded box connection 4 and threaded pin connection 6 permit the drill pipe 1 to be connected to other lengths of drill pipe (not shown) to form a drill string for drilling a borehole, such as an oil/or gas well.
The tube 2 also has an enlarged central portion 7 with a central cylindrical surface 8 which is parallel to the exterior walls of the tube 2 and the longitudinal axis of the drill pipe 1. The cylindrical surface 8 is smooth and is connected to the tube 2 at its upper end by a concave surface 9 and to the lower portion of tube 2 by a convex surface 10. Located in the concave surface 9 are a number of spiral formations 11 which are cut out of the concave surface 9.
The drill pipe 1 shown in Fig. 1 is truncated and the full length of drill pipe 1 would typically have three enlarged central portions 7 spaced along its length between the enlarged end portions 3, 5. Preferably, two of the enlarged central portions 7 have a spiral formation 11 formed in one direction around the circumference of the concave surface 9, and the third enlarged central portion 7 having a spiral formation 11 formed in the other direction.
In addition, hard banding may be applied to the enlarged portion 7, if desired.
An advantage of the drill pipe 1 is that the cylindrical surface 8 is smooth which helps prevent the enlarged section biting into the side walls of the bore hole during drilling. However, the spiral formations 11 help to promote agitation of drill cuttings within the well to mitigate the problems of drill cuttings collecting on the lower side of the well. Typically, the spiral formations 11 would be deeper and wider adjacent the cylindrical surface 8 than adjacent the tube 2.
In addition, the maximum diameter of the enlarged portion 7 is typically less than or equal to the diameter of the enlarged end portions 3, 5.
Fig.2 shows a second example of an enlarged central portion 15 which can be incorporated into a length of the drill pipe 1 shown in Fig. 1 in addition to, or instead of the enlarged central portion 7 of Fig. 1.
The enlarged central portion 15 of Fig. 2 has a similar central cylindrical surface 8 to that of Fig. 1. However, the central cylindrical surface 8 of Fig. 2 is connected to the tube section 2 at its upper end by a convex and radiussed surface 17, into which are cut six spiral formations 19. The central cylindrical surface 8 is connected at its lower end to the tube 2 by a linearly sloping section 21.
As the upper end has a convex and radiused surface 17, the invention has the advantage that a greater surface area of metal may be scooped away to form the spiral formations 19, which increases the efficiency of the invention by causing greater turbulence, in use.
The longitudinal length of each of the linearly sloping section 21, cylindrical surface 8 and the convex and radiussed section 17 is 9". For a tube whose diameter at section B is 5", the diameter of the cylindrical surface 8 is 6V, and for a tube whose diameter at section B is 6%", the diameter of the cylindrical surface 8 is 8V .
Modifications and improvements may be incorporated without departing from the scope of the invention.

Claims

1. A drill pipe (1) comprising a length of conduit (2) having a first diameter, a first (3) and a second (5) end portion, each end portion (3, 5) having a second diameter greater than the first diameter, and an enlarged portion (7, 15) located between and spaced from the first (3) and second (5) end portions, the enlarged portion (7, 15) comprising a central section (8) having a third diameter greater than the first diameter and the central section (8) having a substantially smooth external surface, and two end sections (9, 10; 17, 21), one end section (9, 10; 17, 21) at either end of the central section (8), which vary in diameter between the first and the third diameter, and one of the end sections (9; 17) having a spiral formation (11; 19) thereon.
2. A drill pipe (1) according to claim 1, wherein the spiral formation (11; 19) is located between the central section (8) and the first end portion (3) of the drill pipe (1), where the first end portion (3) is an upper end of the drill pipe (1), in use.
3. A drill pipe (1) according to either of claims 1 or 2 , wherein the external surface of the central section (7, 15) is a substantially cylindrical surface.
4. A drill pipe (1) according to any of the preceding claims wherein three enlarged portions (7, 15) are provided on the drill pipe (1).
5. A drill pipe (1) according to any of the preceding claims wherein the other end section (10) comprises a curved surface which is convex.
6. A drill pipe (1) according to any of the preceding claims, wherein the other end section (10) comprises a curved surface which is radiused.
7. A drill pipe (1) according to any of claims 1 to 4, wherein the other end section (21) comprises a linearly sloping surface.
8. A drill pipe (1) according to any of the preceding claims, wherein the spiral formation (11, 19) is deeper and/or wider adjacent the central section (8).
9. A drill pipe (1) according to any of the preceding claims, wherein the end section (9) in which the spiral formation (11) is formed has a concave shape.
10. A drill pipe (1) according to any of claims 1 to 8, wherein the end section (17) in which the spiral formation (19) is formed comprises a curved surface which is convex.
11. A drill pipe (1) according to any of claims 1 to 8 or claim 10, wherein the end section (17) in which the spiral formation (19) is formed comprises a curved surface which is radiused.
12. A drill pipe (1) according to any of the preceding claims, wherein the third diameter of the enlarged portion (7, 15) is less than or equal to the second diameter of the end portions (3, 5).
13. A drill pipe (1) according to any of the preceding claims, wherein the drill pipe (1) comprises a plurality of enlarged portions (7, 15) spaced along its length.
14. A drill pipe (1) according to claim 13, wherein one or more of the enlarged portions (7, 15) have a spiral formation (11) formed in one direction around the circumference of the one end section (9; 17), and one or more of the enlarged portions have a spiral formation (11) formed in the other direction.
PCT/GB1997/002236 1996-08-27 1997-08-20 A drill pipe WO1998009046A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
CA002263901A CA2263901A1 (en) 1996-08-27 1997-08-20 A drill pipe
DE69712893T DE69712893T2 (en) 1996-08-27 1997-08-20 drill pipe
EP97937683A EP0922153B1 (en) 1996-08-27 1997-08-20 A drill pipe
US09/242,573 US6167917B1 (en) 1996-08-27 1997-08-20 Drill pipe
AU40227/97A AU725911B2 (en) 1996-08-27 1997-08-20 A drill pipe
AT97937683T ATE218181T1 (en) 1996-08-27 1997-08-20 DRILL PIPE
NO990959A NO990959D0 (en) 1996-08-27 1999-02-26 Borer ° r

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB9617819.9A GB9617819D0 (en) 1996-08-27 1996-08-27 A drill pipe
GB9617819.9 1996-08-27

Publications (1)

Publication Number Publication Date
WO1998009046A1 true WO1998009046A1 (en) 1998-03-05

Family

ID=10798948

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1997/002236 WO1998009046A1 (en) 1996-08-27 1997-08-20 A drill pipe

Country Status (9)

Country Link
US (1) US6167917B1 (en)
EP (1) EP0922153B1 (en)
AT (1) ATE218181T1 (en)
AU (1) AU725911B2 (en)
CA (1) CA2263901A1 (en)
DE (1) DE69712893T2 (en)
GB (1) GB9617819D0 (en)
NO (1) NO990959D0 (en)
WO (1) WO1998009046A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2370297A (en) * 2000-12-19 2002-06-26 Gholam Hossein Rastegar Tubing component
WO2002050397A1 (en) * 2000-12-19 2002-06-27 Weatherford/Lamb, Inc. Torque reducing tubing component

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002010630A1 (en) * 2000-08-01 2002-02-07 Grant Prideco, L.P. Wear-resistant tool joint and drill pipe made therefrom
FR2824104A1 (en) 2001-04-27 2002-10-31 Smf Internat Profiled element comprises zone pressing on shaft wall, deflection zone and turbulence zone to improve drilling fluid throughput and reduce cutter wear

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0138603A2 (en) * 1983-10-13 1985-04-24 Texas Forge & Tool Limited Improvements in or relating to rods and pipes
EP0313413A1 (en) * 1987-10-22 1989-04-26 Weatherford U.S. Inc. Flexible drill string member and method of drilling deviated holes
WO1994027024A1 (en) * 1993-05-15 1994-11-24 Arthur Deacey Stewart Drill pipe for directional drilling

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2217592A (en) * 1938-08-01 1940-10-08 Lgs Devices Corp Well reamer
US2589534A (en) * 1947-07-28 1952-03-18 Ralph Q Buttolph Drill guiding assembly
US2676820A (en) * 1951-09-24 1954-04-27 Reed Roller Bit Co Drill collar
US4146060A (en) * 1977-07-25 1979-03-27 Smith International, Inc. Drill pipe wear belt assembly
FR2517357A1 (en) 1981-11-27 1983-06-03 Smf Int Boring rod for ground working - is divided into three zones with centre having hard covering and shearing neck at top
US4549613A (en) * 1982-07-30 1985-10-29 Case Wayne A Downhole tool with replaceable tool sleeve sections
US4760889A (en) * 1986-09-19 1988-08-02 Dudman Roy L High bending strength ratio drill string components
GB8908014D0 (en) * 1989-04-10 1989-05-24 Smith Int North Sea A milling tool stabiliser
GB9022062D0 (en) * 1990-10-10 1990-11-21 Petco Fishing & Rental Tools U Milling tool

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0138603A2 (en) * 1983-10-13 1985-04-24 Texas Forge & Tool Limited Improvements in or relating to rods and pipes
EP0313413A1 (en) * 1987-10-22 1989-04-26 Weatherford U.S. Inc. Flexible drill string member and method of drilling deviated holes
WO1994027024A1 (en) * 1993-05-15 1994-11-24 Arthur Deacey Stewart Drill pipe for directional drilling

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2370297A (en) * 2000-12-19 2002-06-26 Gholam Hossein Rastegar Tubing component
WO2002050397A1 (en) * 2000-12-19 2002-06-27 Weatherford/Lamb, Inc. Torque reducing tubing component

Also Published As

Publication number Publication date
CA2263901A1 (en) 1998-03-05
DE69712893D1 (en) 2002-07-04
DE69712893T2 (en) 2003-01-23
NO990959L (en) 1999-02-26
US6167917B1 (en) 2001-01-02
EP0922153B1 (en) 2002-05-29
ATE218181T1 (en) 2002-06-15
EP0922153A1 (en) 1999-06-16
AU4022797A (en) 1998-03-19
AU725911B2 (en) 2000-10-26
NO990959D0 (en) 1999-02-26
GB9617819D0 (en) 1996-10-09

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