EP1254299A2 - Appareil de protection et de reduction du couple d'une tige de forage - Google Patents

Appareil de protection et de reduction du couple d'une tige de forage

Info

Publication number
EP1254299A2
EP1254299A2 EP01904095A EP01904095A EP1254299A2 EP 1254299 A2 EP1254299 A2 EP 1254299A2 EP 01904095 A EP01904095 A EP 01904095A EP 01904095 A EP01904095 A EP 01904095A EP 1254299 A2 EP1254299 A2 EP 1254299A2
Authority
EP
European Patent Office
Prior art keywords
low friction
collar
mandrel
coating
collar member
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.)
Withdrawn
Application number
EP01904095A
Other languages
German (de)
English (en)
Inventor
Arthur Deacey Stewart
Mark William Craig
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Stable Services Ltd
Original Assignee
Stable Services Ltd
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 Stable Services Ltd filed Critical Stable Services Ltd
Publication of EP1254299A2 publication Critical patent/EP1254299A2/fr
Withdrawn legal-status Critical Current

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
    • E21B17/1057—Centralising devices with rollers or with a relatively rotating sleeve
    • E21B17/1064—Pipes or rods with a relatively rotating sleeve

Definitions

  • the present invention relates to improved pipe torque-reduction and protection devices for use m drill strings. More particularly, the invention relates to improved drill pipes and sub-assemblies ("subs") incorporating means for protecting drill pipe, boreholes or borehole casings and/or reducing the torque generated when rotating a drill string within a borehole or borehole casing.
  • subs sub-assemblies
  • a variety of devices are known for protecting drill pipe/casing and for reducing torque. These include collars or sleeves which are secured around the main tubular body of the drill pipe. Such collars may be securely fixed to the drill pipe so as to rotate with the drill pipe under all conditions (“rotating" collars) or may be rotatable relative to the drill pipe, so that the collar ceases rotating (or reduces its rate of rotation) m the event of contact with the interior of the borehole or casing ("non- rotating" collars); i.e. the drill pipe rotates relative to the non-rotating collar.
  • Known devices also include sub-assemblies (“subs”) incorporating rotating or non-rotating collars which are connected between adjacent lengths of drill pipe.
  • Protective collars of these types are formed from a variety of materials including plastics, elastomers and alloys, generally including low-friction materials on the outer surfaces of the collars and, m the case of non-rotating types, including a variety of bearing arrangements to allow rotation relative to the pipe body or the body of the sub-assembly. It s also known to incorporate protective and/or torque- reducing upsets into the mam body of the drill pipe. Devices of this type perform an additional function in stabilising the drill string and thereby reducing vibration of the string m use.
  • the present invention relates to improved torque- reducing and/or protection devices which can be configured as subs and which can also be incorporated into the tool joints of lengths of drill pipe. It has not hitherto been known to incorporate devices of this type into the tool joints of drill pipe.
  • the invention m its various aspects, relates to a torque-reduction and/or protection device for use in a drill string, of the type comprising a generally cylindrical body adapted to form part of a drill string, said body including a mandrel portion, and a collar member rotatably mounted on said mandrel portion.
  • the body and the collar member are formed from suitable rigid alloys (normally steel) , and low friction bearing means is provided between the collar and the mandrel including at least one of the following on the bearing surfaces of each of the collar and mandrel : low friction alloy coating; low friction ceramic coating; low friction alloy insert; low friction ceramic insert; magnetic elements.
  • the collar member and mandrel each include low friction ceramic inserts on their bearing surfaces.
  • the collar member includes cylindrical inserts extending around its inner circumference and the mandrel includes disk-shaped ceramic inserts located recesses on its outer surface.
  • said bearing means defines two annular bands of bearing elements between the mandrel and collar, adjacent opposite longitudinal ends thereof.
  • the collar member has a low friction coating on its outer surface, said coating comprising a composite coating having an inner layer of hard low friction material and an outer coating of relatively softer low friction material.
  • said inner coating comprises ceramic material and said outer coating comprises plastic material (most preferably nylon) .
  • the collar member has a generally convex outer surface in longitudinal cross section.
  • the collar member is mounted on the mandrel portion between first and second shoulders, one of said shoulders being defined by a ring member secured to said body after said collar member has been located thereon.
  • said ring member is secured to said body by thermal shrink fitting.
  • mating surfaces of said ring member and said body are shot- blasted prior to the ring member being fitted to the body.
  • mating surfaces of said ring member and said body are provided with complementary, interlocking projections and recesses providing a mechanical interlock therebetween.
  • said interlock is formed by cold forming the lock ring to engage a recess or recesses formed in the outer surface of the body.
  • lock ring is threadably secured to the body by a reverse hand thread (as defined herein) .
  • said cylindrical body comprises a sub adapted for connection in a drill string.
  • said cylindrical body comprises a pipe tool joint adapted to form a tool joint of a length of drill pipe.
  • a drill pipe comprising a mothertube and first and second tool joints at either end thereof, wherein one of said tool joints incorporates a torque-reduction and/or protection device of the type comprising a generally cylindrical body adapted to form part of a drill string, said body including a mandrel portion, and a collar member rotatably mounted on said mandrel portion.
  • the device may incorporate any of the first to third aspects of the invention.
  • a method of manufacturing a drill pipe accordance with the fourth aspect comprises the steps of removing a tool joint, or portion thereof, from a conventional drill pipe and replacing said tool joint or part thereof with a modified tool joint or part thereof incorporating said device.
  • Fig. 1 is a side view, partly section, of one embodiment of a sub incorporating a torque- reduction/protection device in accordance with the invention
  • Fig. 2A is a side view of a mam body portion of one embodiment of the sub of Fig. 1 ;
  • Fig. 2B is a side view of a mam body portion of a preferred embodiment of the sub of Fig. 1;
  • Fig. 2C is a detail view of part of the main body portion of Fig. 2B;
  • Figs. 3A and 3B are, respectively, side and transverse sectional views of a portion of the sub of Fig . 1 ;
  • Figs. 4A is a sectional side view of a main collar member of the sub of Fig. 1 and Figs. 4B and 4C are sectional side and end views of bearing inserts for use with the collar member of Fig. 4A;
  • Figs. 5A, 5B and 5C are, respectively, a sectional side view and first and second end views of a locking ring forming part of the sub of Fig. 1 ;
  • Fig. 6 is a cut-away side view of a preferred embodiment of the sub of Fig. 1, employing the main body portion of Fig. 2B;
  • Fig. 7 is a cut-away side view of a portion of one embodiment of a length of drill pipe incorporating a torque-reduction/protection device, similar to that used in the sub of Fig. 6, in accordance with the invention;
  • Fig. 8 is a sectional side view of a portion of a second embodiment of a length of drill pipe incorporating a torque-reduction/protection device in accordance with the invention; and Figs. 9A, 9B and 9C illustrate a preferred embodiment of a bearing which may be employed in embodiments of the present invention.
  • a sub in accordance with the invention comprises a generally cylindrical main body portion 10 having a through bore 12, a threaded male connector (“pin”) 14 at one end and a threaded female connector (“box”) 16 at the opposite end.
  • pin threaded male connector
  • box threaded female connector
  • the body 10 includes a mandrel portion 18, upon which is mounted a generally cylindrical collar member 20 which is rotatable relative to the body 10.
  • the mandrel portion 18 and collar 20 are located between first and second raised shoulder portions 22 and 24, which have an outside diameter greater than the outside diameter of the remainder of the body 10 which includes the mandrel portion 18.
  • the first shoulder 22 is preferably formed integrally with the main body 10, whilst the second shoulder 24 preferably comprises a lock ring member which is fitted to the body 10 after the collar has been slid along the body 10 into location on the mandrel portion 18. Drill pipe and subs forming a drill string are normally inserted into a borehole pin-end down.
  • integrally-formed shoulder 22 is on the side of the mandrel 18 closest to the pin 14 (i.e. the "downward” end, in use) whilst the lock ring 24 is on the side of the mandrel 18 closest to the box 16 (i.e. the "upward” end, in use) .
  • Some drill pipes and subs are designed to be inserted box-end down, in which case this arrangement would preferably be reversed.
  • a stress-relief groove (not shown) , typically having a part circular cross section, is preferably formed around the angle between the integral shoulder 22 and . the body 10.
  • the lock ring 24 would normally be non-removable, and may be secured to the body by any suitable means.
  • the lock ring 24 is shrink-fitted onto the body 10; i.e. the lock ring 24 is formed with an inner diameter slightly less than the outer diameter of the body 10, heated to increase its inner diameter so as to enable it to fit over the end of the body 10 and subsequently cooled so as to shrink onto the body 10.
  • the inner surface of the lock ring 24 and the corresponding outer surface of the body 10 are preferably shot-blasted or otherwise treated to increase the friction between the two when the lock ring 24 is in place.
  • the mating surfaces of the lock ring 24 and body 10 may be formed with complementary projections and recesses in order to provide a mechanical interlock between the two; e.g. one or more annular ridges could be formed on the inner surface of the lock ring 24 and complementary annular grooves formed around the external surface of the body 10.
  • the body 10 may be formed with an annular groove 60 (see Figs. 2B and 2C) and the lock ring provided with an annular groove 62 extending around its external surface (see Fig. 5A) .
  • the lock ring is deformed by cold forming after shrink fitting so that its interior surface interlocks with the groove 60 of the body 10.
  • lock ring 24 might be threadably connected to the body, employing a left hand thread (i.e. a thread of opposite hand to the mam drill string connections) , as shall be discussed further below.
  • the shoulder portions 22 and 24 have outer surfaces which taper from a maximum outside diameter to the outside diameter of the body, the directions towards the adjacent ends of the body 10.
  • the body 10, collar member 20 and lock ring 24 are all formed of steel or other suitable alloy (s) .
  • the annular bearing surfaces of the shoulders 22 and 24 and/or the annular end surfaces of the collar 20 are preferably formed from low friction alloy (s) .
  • a low friction bearing is provided between the collar 20 and the mandrel 18.
  • the mandrel 18 is formed with recesses its outer surface, in which ceramic discs 26 are mounted and machined to form a smooth, continuous surface.
  • the inner surface of the collar member 20 is formed to receive cylindrical ceramic inserts 28 inserted from either end thereof .
  • the inserts 28 could be of low friction alloy or could be formed from steel with ceramic elements inserted therein.
  • the bearing surfaces can be provided with low friction coatings; e.g. ceramic or low friction alloy material applied by spray fusion methods. Where ceramic materials are used, these are preferably of a relatively pliable type.
  • the mandrel 18 and/or collar 20 may include magnetised elements so as to provide a magnetic repulsion bearing.
  • the configuration of the bearing and the types of materials employed may be varied provided that the resulting bearing is capable of sustaining high loads over a reasonable lifetime.
  • Figs. 9A, 9B and 9C illustrate a preferred form of bearing which may be employed in any of the embodiments of the invention.
  • First sets of inner ceramic disks 70 are provided on the mandrel, located in holes formed around the circumference of the outer surface of the mandrel.
  • the inner disks 70 have convex outer surfaces 72 which match the curvature of the mandrel surface.
  • Second sets of outer ceramic disks 74 are provided on the collar, located in holes formed around the circumference of the inner surface of the collar.
  • the outer disks 74 have concave outer surfaces 76 which match the curvature of the inner surface of the collar. As shown in Figs.
  • the bearing may comprise two annular bands of ceramic disks, each band comprising a pair of rings of ceramic disks, located adjacent either end of the mandrel/collar.
  • the outer surface of the collar 20 preferably has a slightly convex configuration m longitudinal cross section, most preferably arcuate but alternatively a non-arcuate curved profile or a combination of straight line segments and/or curved segments, so as to minimise the contact area between the collar and a casmg/borehole wall.
  • the outer surface of the collar 20 will contact the interior surface of the borehole casing and/or the open borehole wall . When such contact occurs, the body 10 will rotate within the collar 20.
  • the outer surface of the collar 20 is preferably provided with a low friction coating 30 (the thickness of the coating is exaggerated the drawings) .
  • the coating 30 comprises a composite coating having an inner layer of hard-wearing, low friction material 13 such as ceramic or alloy materials (suitably similar to those which may be employed m the mam collar bearing) applied oy spray fusion methods, and an outer layer of relatively softer low friction material, suitably a polymer material such as nylon, which may also be applied by spray techniques.
  • the outer coating will provide low friction contact without damaging the casing wall.
  • the outer coating will erode relatively quickly, exposing the hard-wearing inner layer.
  • the inner layer might typically be about 0.5 mm (0.02 inches) thickness and the outer layer about 2 mm to 2.5 mm (0.08 to 0.1 inches) in thickness .
  • the design of the sub is relatively simple and very robust, being relatively inexpensive to manufacture and refurbish.
  • the collar 20 may be removed by machining off the lock ring 24, which may be regarded as a consumable item, to allow refurbishment of the outer and inner bearing surfaces of the collar 20 and/or the outer bearing surface of the mandrel 18.
  • Figs. 2B and 6 show a slightly modified embodiment of a sub, in which the profiles of the shoulder portions 22A and 24A differ from those of the preceding embodiment. It is still preferred that the pm-end (downward end) shoulder 22A is integrally formed with the mam body 10 and the box-end (upper end) shoulder 24A comprises a lock ring, as previously described. Whilst the embodiments of the invention described thus far improve upon existing sub- type designs of torque-reduction/protection devices, there are disadvantages m employing subs a drill string. Expense is incurred in making up connections between drill string components and it is desirable to minimise the number of connections for this reason and also to avoid reducing the mechanical integrity of the drill string.
  • subs generally produce local increases in the stiffness of the drill string which is disadvantageous, particularly m directional drilling. This is exacerbated by the fact that subs must have a certain minimum length to allow them to be gripped by power tongs for making up threaded connections.
  • the present torque- reduction/protection device may be incorporated into the tool joint of a length of drill pipe, as illustrated m Figs. 7 and 8.
  • Fig. 7 shows a box-end portion of a length of drill pipe comprising a mothertube portion 40 and a tool joint portion 42, as is well known the art.
  • the tool joint portion 42 incorporates a torque- reduction/protection device which may be similar to those previously described with reference to Figs. 1 to 6.
  • the device is 15 substantially identical to that of Fig. 6, like features being designated by like reference numerals, and will not be described m detail.
  • the drill pipe could be manufactured initially the manner illustrated, or a conventional drill pipe could be converted by removing the conventional tool joint, or a part thereof, and replacing it with a modified tool joint portion 42 incorporating a torque-reduction/protection device m accordance with the present invention.
  • the conventional tool joint could be cut at line 44 and a replacement tool joint portion 42 friction welded to the end of the remaining drill pipe, or the conventional tool joint could be cut at line 46 and a replacement tool joint portion stub welded to the remaining drill pipe.
  • the device incorporated into the tool joint 42 may include any of the features or variations previously described in relation to Figs. 1 to 6.
  • Fig. 8 illustrates a second embodiment of a pipe tool joint incorporating a device m accordance with the invention.
  • like reference numerals designate features corresponding to features of Fig. 7.
  • the basic mandrel, collar and bearing arrangements may be the same as or similar to those described relation to the preceding embodiments.
  • this embodiment may be implemented by removing the conventional tool joint of a drill pipe welding the tool joint to end of the remaining pipe at line 44A by friction welding.
  • the integral shoulder 48 is adjacent the free end of the tool joint 42 and the lock ring 50 threadably engages a corresponding threaded portion 52 formed on the other side of the mandrel 18 from the integral shoulder 48.
  • the lock ring 50 has a left handed thread, so that any torque applied to the lock ring as a result of rotation of the drill string in normal use will tend to tighten the lock nut 50.
  • the "hand" of the thread to achieve this effect will thus depend on which end of the drill pipe incorporates the device, the intended direction of rotation of the drill pipe etc.
  • the lock ring thread will be of opposite hand to the threads of the box/pm connections of the drill pipe.
  • the term "reverse- hand thread” is used herein to specify a thread of hand which will tend to tighten in response to rotation of the drill string in its usual working conditions.
  • the lock ring 50 is preferably formed with a uniform outer diameter and secured to the tool joint 42 after the collar 20 has been installed. Thereafter, the shaded area 50S of the lock ring 50 is machined off to provide an inclined surface facing the direction of insertion of the drill pipe, suitably co-linear with the adjacent profile of the tool joint.
  • the inner diameters of the collar 20 and lock ring 50 are sufficiently large to pass over the pin-end tool joint (not shown) of the drill pipe. For this reason, it is preferred that this embodiment be applied to the box-end tool joint of the pipe.
  • embodiments of the present invention may incorporate features which are known from existing torque-reduction/protection devices, if considered necessary or desirable in particular circumstances, such as flutes or other fluid passages in the main bearing between the collar and the mandrel and/or in the outer surface of the collar.

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)

Abstract

L'invention concerne un dispositif de protection et/ou de réduction du couple s'utilisant dans un train de forage qui comprend un corps généralement cylindrique (10) comprenant un mandrin (18) et un collier rotatif (20) monté sur le mandrin entre des premier et second épaulements (22, 24), un desquels est défini par un élément annulaire (24) fixé audit corps une fois le collier mis en place. Un palier à faible frottement est placé entre le collier et le mandrin, et comprend au moins une des surfaces d'appui du collier et du mandrin : un revêtement en alliage à faible frottement, un revêtement en céramique à faible frottement, un insert en alliage à faible frottement, un insert en céramique à faible frottement et des éléments magnétiques. Le collier possède un revêtement à faible frottement (30) sur sa surface extérieure qui comprend un revêtement composite pourvu d'une couche intérieure en matériau solide à faible frottement et d'une couche extérieure en matériau relativement souple à faible frottement. Le dispositif peut être introduit dans un raccord, mais il est de préférence introduit dans un joint de tige d'une longueur de tige de forage.
EP01904095A 2000-02-10 2001-02-08 Appareil de protection et de reduction du couple d'une tige de forage Withdrawn EP1254299A2 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB0002916 2000-02-10
GB0002916A GB0002916D0 (en) 2000-02-10 2000-02-10 Drill pipe torque reduction and protection apparatus
PCT/GB2001/000486 WO2001059249A2 (fr) 2000-02-10 2001-02-08 Appareil de protection et de reduction du couple d'une tige de forage

Publications (1)

Publication Number Publication Date
EP1254299A2 true EP1254299A2 (fr) 2002-11-06

Family

ID=9885209

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01904095A Withdrawn EP1254299A2 (fr) 2000-02-10 2001-02-08 Appareil de protection et de reduction du couple d'une tige de forage

Country Status (5)

Country Link
EP (1) EP1254299A2 (fr)
AU (1) AU2001232014A1 (fr)
GB (1) GB0002916D0 (fr)
NO (1) NO20023760L (fr)
WO (1) WO2001059249A2 (fr)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1291486A1 (fr) * 2001-09-07 2003-03-12 Shell Internationale Researchmaatschappij B.V. Tubage enroulé rotatif
NO326223B1 (no) 2003-10-29 2008-10-20 Weatherford Lamb Apparat og fremgangsmate for a redusere borevibrasjon ved boring med fôringsror
ATE383450T1 (de) 2005-11-22 2008-01-15 Mec Holding Gmbh Werkstoff für teile oder beschichtungen, die verschleiss oder reibung ausgesetzt sind, verfahren zu deren herstellung und verwendung des werkstoffes in einer vorrichtung zur drehmomentreduzierung bei bohrstrangkomponenten
US8220563B2 (en) * 2008-08-20 2012-07-17 Exxonmobil Research And Engineering Company Ultra-low friction coatings for drill stem assemblies
EP2417324B1 (fr) 2009-04-07 2017-05-17 Frank's International, Inc. Bande d'usure réduisant la friction et procédé de couplage d'une bande d'usure à un élément tubulaire
JP6672911B2 (ja) * 2015-03-13 2020-03-25 日本製鉄株式会社 坑井の掘削方法、その掘削方法に用いられるドリルパイプ及びツールジョイント
JP6569355B2 (ja) * 2015-07-27 2019-09-04 日本製鉄株式会社 坑井の掘削方法、その掘削方法に用いられるドリルパイプ及びツールジョイント
US11352840B2 (en) 2017-08-01 2022-06-07 Frank's International, Llc Drill pipe torque reducer and method
GB2606714B (en) * 2021-05-13 2023-11-22 Rotojar Innovations Ltd Downhole torque reducer
CN113464064B (zh) * 2021-08-06 2023-07-21 西南石油大学 一种超深井小尺寸钻杆扭矩过载保护方法及装置

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US1824257A (en) * 1928-01-30 1931-09-22 Reed Roller Bit Co Tool joint
GB307212A (en) * 1928-03-06 1929-03-07 James Cuthill Improvements relating to drill-pipes for well boring
US1877395A (en) * 1928-05-14 1932-09-13 Emsco Derrick & Equip Co Antifriction device for drill pipe
WO1994003700A1 (fr) * 1991-06-10 1994-02-17 Prideco, Inc. Tige de forage legere
DE4127249C1 (fr) * 1991-08-17 1993-02-04 Gd-Anker Gmbh, 3370 Seesen, De
GB9207624D0 (en) * 1992-04-08 1992-05-27 Strange Anthony E J Improvements relating to the protection of corrosion-susceptible members
US5778976A (en) * 1994-02-14 1998-07-14 Austoil Technology Limited Casing installation equipment
AU3144995A (en) * 1994-07-28 1996-02-22 Jerome Kemick Sacrificial wear bearing
AU710050B2 (en) * 1995-08-30 1999-09-09 Drilltech Services (Asia) Pte Limited Friction-reducing drill pipe component
GB9814230D0 (en) * 1998-07-02 1998-09-02 Appleton Robert P Torque reducing substitute

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Title
See references of WO0159249A3 *

Also Published As

Publication number Publication date
NO20023760D0 (no) 2002-08-08
WO2001059249A3 (fr) 2002-01-31
GB0002916D0 (en) 2000-03-29
AU2001232014A1 (en) 2001-08-20
NO20023760L (no) 2002-09-03
WO2001059249A2 (fr) 2001-08-16

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