US20150368984A1 - Pressure Compensated Rotating Electrical Contact - Google Patents
Pressure Compensated Rotating Electrical Contact Download PDFInfo
- Publication number
- US20150368984A1 US20150368984A1 US14/709,396 US201514709396A US2015368984A1 US 20150368984 A1 US20150368984 A1 US 20150368984A1 US 201514709396 A US201514709396 A US 201514709396A US 2015368984 A1 US2015368984 A1 US 2015368984A1
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- Prior art keywords
- component
- recited
- race
- bearing
- electrical contact
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- Abandoned
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Images
Classifications
-
- 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
- E21B17/02—Couplings; joints
- E21B17/028—Electrical or electro-magnetic connections
-
- 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
- E21B17/02—Couplings; joints
- E21B17/023—Arrangements for connecting cables or wirelines to downhole devices
-
- 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
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/05—Swivel joints
-
- 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
- E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
- E21B19/16—Connecting or disconnecting pipe couplings or joints
Definitions
- a wellbore is formed in a hydrocarbon-bearing formation and a well string is deployed in the wellbore.
- the well string is formed with tubing and other types of downhole components, some of which are electrically operated or comprise electrical devices.
- an electrical contact is formed between a rotating component and a stationary component via a slip ring to enable electrical communication with a downhole electrical device.
- the high pressures, dirty environments, and shocks that often occur in a downhole environment can have a detrimental impact on the functionality and longevity of the electrical contact.
- a system and methodology are provided to facilitate communication of electrical signals in harsh environments and between components that undergo relative rotation with respect to each other.
- the technique comprises rotatably mounting a first component with respect to a second component.
- the first component also is electrically coupled with the second component via an electrical coupler.
- the electrical coupler may comprise a first electrical contact located at the first component and a second electrical contact located at the second component.
- the first electrical contact is conductively connected with the second electrical contact via a conductive bearing, e.g. a sliding bearing, a rolling element type bearing, or other suitable bearing.
- the conductive bearing is located in a volume which is filled with a substantially incompressible fluid to protect the bearing.
- FIG. 1 is a schematic illustration of an example of a system having components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure
- FIG. 2 is a cross-sectional view of an example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure
- FIG. 3 is a cross-sectional view of another example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure
- FIG. 4 is a cross-sectional view of another example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure.
- FIG. 5 is a cross-sectional view of another example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure.
- the present disclosure generally relates to a system and methodology for facilitating communication of electrical signals between components which rotate relative to each other.
- the system and methodology for communicating electrical signals are useful in a variety of harsh environments, e.g wellbore environments.
- the technique comprises rotatably and electrically coupling a first component with a second component.
- the first component may be electrically coupled with the second component via an electrical coupler.
- the electrical coupler utilizes a first electrical contact conductively connected with a second electrical contact via a conductive bearing.
- the conductive bearing may be in the form of a plain bearing, e.g. sliding bearing, or a rolling-type bearing, e.g. a cylindrical roller bearing or a ball bearing.
- the conductive bearing is located in a volume which is filled with a substantially incompressible fluid to protect the bearing.
- the electrical coupling utilizes a pressure permeable housing in combination with the conductive bearing, e.g. a rolling bearing.
- the rolling bearing may comprise a ball bearing in the form of a shielded or sealed ball bearing unit.
- the pressure permeable housing may be packed with grease or another suitable fluid that is substantially incompressible.
- the grease or other fluid may be de-gassed to further reduce its compressibility.
- the bearing is protected against overheating via operation at a relatively slow speed and/or via flow of cooling fluid past the bearing.
- a cooling flow of fluid may be directed past the electrical coupling to remove heat generated by the bearing.
- a flow of drilling mud may be used to provide the cooling.
- the bearing can be used to perform a dual duty of providing both a conductive path between components undergoing relative rotation and as a bearing to facilitate the relative rotation.
- the electrical coupler may be constructed to provide a sealed electrical path through the races of the bearing, thus allowing electrical signals to be passed between the components.
- the electrical signals are passed between a rotatable shaft and an adjacent housing via conductive, rolling contact elements of a bearing placed between the rotatable shaft and the adjacent housing.
- a system 20 e.g. a well system, is illustrated as having a first component 22 which is rotatable with respect to a second component 24 .
- Electrical signals routed along a conductor 26 e.g. an electrical communication line, pass between the first component 22 and the second component 24 via an electrical coupler 28 .
- the electrical signals may be sent to or transmitted from an electrical device 30 .
- system 20 is in the form of a well system comprising a well string 32 , e.g. a tubing string, extending along a wellbore 34 from a wellhead, a drilling rig, or other suitable surface equipment 36 .
- a well string 32 e.g. a tubing string
- one of the components 22 , 24 is stationary while the other is rotatable.
- first component 22 may be stationary with respect to the portions of well string 32 above component 22 while the second component 24 is rotatable with respect to first component 22 .
- the components 22 , 24 may be rotated at different speeds relative to a third reference and/or they may be rotated at the same speed during certain periods of operation.
- the rotatable second component 24 may comprise a shaft or a variety of other types of rotatable components. It should be noted the electrical coupler 28 also may be used in a variety of surface or non-well related applications to facilitate transmission of electrical signals between components that undergo relative rotation with respect to each other.
- the electrical coupler 28 comprises a housing 38 which may be part of or attached to first component 22 .
- the housing 38 is engaged with second component 24 in a manner which allows relative rotation between the housing 38 /first component 22 and the second component 24 .
- the second component 24 may comprise a rotatable shaft 40 which rotates about an axis 42 .
- the electrical coupling 28 further comprises an electrical contact 44 positioned at the first component and another electrical contact 46 positioned at the second component.
- a bearing 48 is mounted between the first component 22 and the second component 24 , e.g. between housing 38 and shaft 40 .
- the bearing 48 may comprise a variety of sliding-type bearings or rolling-type bearings, e.g. ball bearings, cylindrical roller bearings, or rolling pin bearings.
- the bearing 48 also is formed of a conductive material, e.g. a conductive steel material, to enable efficient transfer of electrical signals between electrical contacts 44 and 46 .
- bearing 48 comprises a first race 50 mounted against first component 22 and in contact with first electrical contact 44 .
- the bearing 48 also comprises a second race 52 mounted against second component 22 and in contact with second electrical contact 46 .
- the electrical contacts 44 , 46 are otherwise insulated but conductively connected to the races 50 , 52 , respectively, so that an electrical signal may pass through bearing 48 .
- the bearing 48 further comprises a plurality of rotatable members 54 which are rotatably trapped between the first race 50 and the second race 52 .
- bearing 48 is in the form of a plain bearing having sliding contact surfaces which may be lubricated.
- bearing 48 may be in the form of a rolling-type bearing having rolling contact elements in the form of rotatable members 54 .
- rotatable members 54 may be cylindrical rollers, balls, pins, or other suitable rotatable members.
- bearing 48 may be in the form of a shielded or sealed unit bearing.
- the bearing 48 also may be electrically isolated via insulating material or insulating devices so that short circuits do not occur.
- the bearing races 50 , 52 or other bearing components may be formed partially of plastic or other materials and provided with conductive contacts to maintain the electrical connection during relative rotation of first component 22 with respect to second component 24 .
- the bearing 48 is located in a cavity 56 disposed between the first component 22 and the second component 24 .
- the cavity 56 may be formed in housing 38 and may extend to second component 24 .
- the cavity 56 has a volume for receiving a substantially incompressible fluid 58 which surrounds at least a portion of the bearing 48 .
- the substantially incompressible fluid 58 may be in the form of grease. Additionally, the substantially incompressible fluid 58 may be de-gassed to further reduce its compressibility.
- the electrical coupler 28 also is constructed to enable pressure equalization between the cavity 56 and an exterior region 60 outside of cavity 56 and housing 38 .
- the pressure equalization may be achieved through a porous material 62 .
- the porous material 62 may be in the form of a porous gland/membrane 64 placed between the first component 22 , e.g. the stationary component, and the second component 24 , e.g. the rotary component.
- fluid that enters cavity 56 is effectively isolated from the bearing 48 . At most, minute volumes of external fluid can enter the cavity 56 before the pressures are equalized. Once equilibrium is achieved, there is no mechanism to further drive the exterior fluid into bearing 48 .
- the porous gland 64 may further be used to filter out abrasive particles from external fluid which enters cavity 56 .
- the porous gland 64 also blocks fluid flow which could potentially remove the grease or other incompressible fluid 58 from cavity 56 .
- the porous gland/membrane 64 also may be originally filled with a clean and neutral fluid 66 , e.g. oil or grease, such that minute amounts of this clean and neutral fluid 66 are displaced into cavity 56 during pressure equalization.
- the clean and neutral fluid 66 may have a volume greater than the change in volume of the fluid 58 in cavity 56 when placed under hydrostatic compression resulting from the incoming external fluid that drives the clean fluid 66 from the pores of porous material 62 . Undesirable, external borehole fluid is thus maintained in external region 60 outside of cavity 56 .
- the porous gland 64 may be in the form of a felt material, and the clean fluid 66 may be in the form of a grease impregnating the felt material.
- porous gland 64 various other porous materials 62 may be used to construct porous gland 64 including sponge materials, porous metals, porous composites, and/or other suitably porous materials.
- porous materials 62 may be used to construct porous gland 64 including sponge materials, porous metals, porous composites, and/or other suitably porous materials.
- a variety of greases, viscous liquids, and other suitable fluid and material mixtures may be used for fluids 58 and 66 .
- fluid 66 and fluid 58 may be of the same type of fluid or of different types of fluid.
- the volume of grease or other substantially incompressible fluid 58 is large enough, a “stirring” effect resulting from rotation of the bearing 48 does not reach the outer zones of cavity 56 .
- the size of cavity 56 may thus be used to further limit the ability of external fluid to migrate to the bearing 48 if minute amounts of such external fluid move into the outer reaches of cavity 56 .
- the shielded or sealed bearings 48 also are filled with grease or another suitable fluid. In some applications, the shielded or sealed bearings 48 may be in the form of standard shielded or sealed bearings.
- housing 38 is a porous housing formed at least in part of porous material 62 .
- the porous material 62 used to form housing 38 may be a different type of material than the porous material used to form porous gland/membrane 64 .
- the porous gland 64 may be a soft material, e.g. felt, and the porous material 62 used to form porous housing 38 may be a harder material which retains its form.
- harder, porous material comprise a porous metallic material, porous ceramic material, or porous composite material.
- a specific example of a material comprises (Mite® Bearing material available from Beemer Precision, Inc.
- the pores of porous housing 38 may be pre-loaded with clean fluid 66 .
- the clean fluid 66 may be a suitable grease, oil, or other material. Considerable volumes of clean fluid 66 may be held in the porous material of housing 38 for the purpose of pressure compensation. The large areas exposed to pressure allow the housing 38 to transmit balancing fluid more quickly and to thus support quicker pressure compensation.
- a variety of seals 68 e.g. conventional shaft seals, may be disposed between the first component 22 and second component 24 , as illustrated.
- the structure illustrated in FIG. 3 facilitates operation of the system with considerable pressure gradients acting across the bearing 48 .
- the bearing 48 may be electrically isolated so that electrical signals can pass between electrical contacts 44 , 46 without creating a short-circuit.
- housing 38 is a solid housing and seals 68 are used between first component 22 and second component 24 , as illustrated in FIG. 4 .
- a porous element 70 is located in housing 38 and extends through housing 38 between cavity 56 and exterior region 60 .
- the porous element 70 is formed with a suitable porous material 62 so as to facilitate pressure equalization.
- the pores of porous material 62 may be filled with clean fluid 66 .
- the porous element 70 is sized properly so as to act as a clean fluid reservoir while remaining sealed at the interface with the surrounding portions of housing 38 .
- housing 38 is again a solid housing and seals 68 are used between first component 22 and second component 24 .
- the porous element 70 is located in second component 24 and extends through the second component 24 between cavity 56 and exterior region 60 .
- the second component 24 may be in the form of shaft 40 and porous element 70 may be routed along shaft 40 for exposure to both cavity 56 and exterior region 60 .
- the entire shaft 40 may be formed from porous material 62 so as to facilitate a greater rate of pressure equalization.
- the pores of porous material 62 also may be filled with clean fluid 60 .
- both first component 22 and second component 24 (or portions of each of the components 22 , 24 ) may be formed of a suitable porous material 62 .
- system 20 may have a variety of configurations comprising other and/or additional components.
- shape and structure of the components 22 and 24 may vary in size and configuration depending on the parameters of a given application and environment.
- a variety of materials may be used to construct the various components of the electrical coupler 28 .
- the system 20 also may utilize many types of electrical devices 30 for various downhole applications or other types of applications.
- the bearing 48 may comprise a variety of plain bearings having conductive sliding contact surfaces or a variety of roller-type bearings having conductive rolling members, e.g. cylinders, balls, pins, or other suitable, conductive rolling contact elements.
Abstract
A technique facilitates communication of electrical signals in harsh environments and between components that undergo relative rotation with respect to each other. The technique comprises rotatably mounting a first component with respect to a second component. The first component also is electrically coupled with the second component via an electrical coupler. The electrical coupler may comprise a first electrical contact located at the first component and a second electrical contact located at the second component. The first electrical contact is conductively connected with the second electrical contact via a conductive bearing. The conductive bearing is located in a volume which is filled with a substantially incompressible fluid to protect the bearing.
Description
- The present document is based on and claims priority to U.S. Provisional Application Ser. No.: 62/014,086, filed Jun. 18, 2014, which is incorporated herein by reference in its entirety.
- In many hydrocarbon well applications, a wellbore is formed in a hydrocarbon-bearing formation and a well string is deployed in the wellbore. The well string is formed with tubing and other types of downhole components, some of which are electrically operated or comprise electrical devices. Sometimes an electrical contact is formed between a rotating component and a stationary component via a slip ring to enable electrical communication with a downhole electrical device. However, the high pressures, dirty environments, and shocks that often occur in a downhole environment can have a detrimental impact on the functionality and longevity of the electrical contact.
- In general, a system and methodology are provided to facilitate communication of electrical signals in harsh environments and between components that undergo relative rotation with respect to each other. The technique comprises rotatably mounting a first component with respect to a second component. The first component also is electrically coupled with the second component via an electrical coupler. The electrical coupler may comprise a first electrical contact located at the first component and a second electrical contact located at the second component. The first electrical contact is conductively connected with the second electrical contact via a conductive bearing, e.g. a sliding bearing, a rolling element type bearing, or other suitable bearing. The conductive bearing is located in a volume which is filled with a substantially incompressible fluid to protect the bearing.
- However, many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.
- Certain embodiments of the disclosure will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood, however, that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein, and:
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FIG. 1 is a schematic illustration of an example of a system having components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure; -
FIG. 2 is a cross-sectional view of an example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure; -
FIG. 3 is a cross-sectional view of another example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure; -
FIG. 4 is a cross-sectional view of another example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure; and -
FIG. 5 is a cross-sectional view of another example of an electrical coupler which couples components which undergo relative rotation with respect to each other, according to an embodiment of the disclosure. - In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
- The present disclosure generally relates to a system and methodology for facilitating communication of electrical signals between components which rotate relative to each other. The system and methodology for communicating electrical signals are useful in a variety of harsh environments, e.g wellbore environments. In many applications, the technique comprises rotatably and electrically coupling a first component with a second component. For example, the first component may be electrically coupled with the second component via an electrical coupler. The electrical coupler utilizes a first electrical contact conductively connected with a second electrical contact via a conductive bearing. By way of example, the conductive bearing may be in the form of a plain bearing, e.g. sliding bearing, or a rolling-type bearing, e.g. a cylindrical roller bearing or a ball bearing. The conductive bearing is located in a volume which is filled with a substantially incompressible fluid to protect the bearing.
- The electrical coupling utilizes a pressure permeable housing in combination with the conductive bearing, e.g. a rolling bearing. In some applications, the rolling bearing may comprise a ball bearing in the form of a shielded or sealed ball bearing unit. The pressure permeable housing may be packed with grease or another suitable fluid that is substantially incompressible. The grease or other fluid may be de-gassed to further reduce its compressibility. The bearing is protected against overheating via operation at a relatively slow speed and/or via flow of cooling fluid past the bearing. In certain wellbore applications, for example, a cooling flow of fluid may be directed past the electrical coupling to remove heat generated by the bearing. In drilling applications, a flow of drilling mud may be used to provide the cooling.
- In some embodiments, the bearing can be used to perform a dual duty of providing both a conductive path between components undergoing relative rotation and as a bearing to facilitate the relative rotation. The electrical coupler may be constructed to provide a sealed electrical path through the races of the bearing, thus allowing electrical signals to be passed between the components. In some applications, the electrical signals are passed between a rotatable shaft and an adjacent housing via conductive, rolling contact elements of a bearing placed between the rotatable shaft and the adjacent housing.
- Referring generally to
FIG. 1 , an example of asystem 20, e.g. a well system, is illustrated as having afirst component 22 which is rotatable with respect to asecond component 24. Electrical signals routed along aconductor 26, e.g. an electrical communication line, pass between thefirst component 22 and thesecond component 24 via anelectrical coupler 28. By way of example, the electrical signals may be sent to or transmitted from anelectrical device 30. - In the specific example illustrated,
system 20 is in the form of a well system comprising awell string 32, e.g. a tubing string, extending along awellbore 34 from a wellhead, a drilling rig, or othersuitable surface equipment 36. In some applications, one of thecomponents first component 22 may be stationary with respect to the portions of wellstring 32 abovecomponent 22 while thesecond component 24 is rotatable with respect tofirst component 22. However, thecomponents second component 24 may comprise a shaft or a variety of other types of rotatable components. It should be noted theelectrical coupler 28 also may be used in a variety of surface or non-well related applications to facilitate transmission of electrical signals between components that undergo relative rotation with respect to each other. - Referring generally to
FIG. 2 , an example of theelectrical coupler 28 is illustrated. In this example, theelectrical coupler 28 comprises ahousing 38 which may be part of or attached tofirst component 22. Thehousing 38 is engaged withsecond component 24 in a manner which allows relative rotation between thehousing 38/first component 22 and thesecond component 24. By way of example, thesecond component 24 may comprise arotatable shaft 40 which rotates about anaxis 42. Theelectrical coupling 28 further comprises anelectrical contact 44 positioned at the first component and anotherelectrical contact 46 positioned at the second component. Additionally, abearing 48 is mounted between thefirst component 22 and thesecond component 24, e.g. betweenhousing 38 andshaft 40. Thebearing 48 may comprise a variety of sliding-type bearings or rolling-type bearings, e.g. ball bearings, cylindrical roller bearings, or rolling pin bearings. Thebearing 48 also is formed of a conductive material, e.g. a conductive steel material, to enable efficient transfer of electrical signals betweenelectrical contacts - In the example illustrated,
bearing 48 comprises afirst race 50 mounted againstfirst component 22 and in contact with firstelectrical contact 44. Thebearing 48 also comprises asecond race 52 mounted againstsecond component 22 and in contact with secondelectrical contact 46. Theelectrical contacts races rotatable members 54 which are rotatably trapped between thefirst race 50 and thesecond race 52. - In an embodiment, bearing 48 is in the form of a plain bearing having sliding contact surfaces which may be lubricated. In other embodiments, bearing 48 may be in the form of a rolling-type bearing having rolling contact elements in the form of
rotatable members 54. By way of example,rotatable members 54 may be cylindrical rollers, balls, pins, or other suitable rotatable members. Additionally, bearing 48 may be in the form of a shielded or sealed unit bearing. The bearing 48 also may be electrically isolated via insulating material or insulating devices so that short circuits do not occur. In some applications, the bearing races 50, 52 or other bearing components may be formed partially of plastic or other materials and provided with conductive contacts to maintain the electrical connection during relative rotation offirst component 22 with respect tosecond component 24. - As illustrated in
FIG. 2 , thebearing 48 is located in acavity 56 disposed between thefirst component 22 and thesecond component 24. By way of example, thecavity 56 may be formed inhousing 38 and may extend tosecond component 24. Thecavity 56 has a volume for receiving a substantiallyincompressible fluid 58 which surrounds at least a portion of thebearing 48. In a variety of applications, the substantiallyincompressible fluid 58 may be in the form of grease. Additionally, the substantiallyincompressible fluid 58 may be de-gassed to further reduce its compressibility. - The
electrical coupler 28 also is constructed to enable pressure equalization between thecavity 56 and anexterior region 60 outside ofcavity 56 andhousing 38. According to an embodiment, the pressure equalization may be achieved through aporous material 62. Theporous material 62 may be in the form of a porous gland/membrane 64 placed between thefirst component 22, e.g. the stationary component, and thesecond component 24, e.g. the rotary component. - By making provision for a volume around the bearing 48 that is filled with nearly
incompressible fluid 58, e.g. grease, fluid that enterscavity 56 is effectively isolated from thebearing 48. At most, minute volumes of external fluid can enter thecavity 56 before the pressures are equalized. Once equilibrium is achieved, there is no mechanism to further drive the exterior fluid intobearing 48. Theporous gland 64 may further be used to filter out abrasive particles from external fluid which enterscavity 56. Theporous gland 64 also blocks fluid flow which could potentially remove the grease or other incompressible fluid 58 fromcavity 56. - The porous gland/
membrane 64 also may be originally filled with a clean andneutral fluid 66, e.g. oil or grease, such that minute amounts of this clean andneutral fluid 66 are displaced intocavity 56 during pressure equalization. The clean andneutral fluid 66 may have a volume greater than the change in volume of the fluid 58 incavity 56 when placed under hydrostatic compression resulting from the incoming external fluid that drives theclean fluid 66 from the pores ofporous material 62. Undesirable, external borehole fluid is thus maintained inexternal region 60 outside ofcavity 56. In some applications, theporous gland 64 may be in the form of a felt material, and theclean fluid 66 may be in the form of a grease impregnating the felt material. However, various otherporous materials 62 may be used to constructporous gland 64 including sponge materials, porous metals, porous composites, and/or other suitably porous materials. Similarly, a variety of greases, viscous liquids, and other suitable fluid and material mixtures may be used forfluids fluid 66 andfluid 58 may be of the same type of fluid or of different types of fluid. - If the volume of grease or other substantially
incompressible fluid 58 is large enough, a “stirring” effect resulting from rotation of thebearing 48 does not reach the outer zones ofcavity 56. The size ofcavity 56 may thus be used to further limit the ability of external fluid to migrate to thebearing 48 if minute amounts of such external fluid move into the outer reaches ofcavity 56. By using shielded or sealedbearings 48, the mechanical stirring effect can further be reduced or eliminated, thus providing additional protection against particles in the substantiallyincompressible fluid 58. The shielded or sealedbearings 48 also are filled with grease or another suitable fluid. In some applications, the shielded or sealedbearings 48 may be in the form of standard shielded or sealed bearings. - Referring generally to
FIG. 3 , another embodiment of theelectrical coupler 28 is illustrated. In this embodiment,housing 38 is a porous housing formed at least in part ofporous material 62. It should be noted, however, theporous material 62 used to formhousing 38 may be a different type of material than the porous material used to form porous gland/membrane 64. For example, theporous gland 64 may be a soft material, e.g. felt, and theporous material 62 used to formporous housing 38 may be a harder material which retains its form. Examples of harder, porous material comprise a porous metallic material, porous ceramic material, or porous composite material. A specific example of a material comprises (Mite® Bearing material available from Beemer Precision, Inc. - In the example illustrated, the pores of
porous housing 38 may be pre-loaded withclean fluid 66. Theclean fluid 66 may be a suitable grease, oil, or other material. Considerable volumes ofclean fluid 66 may be held in the porous material ofhousing 38 for the purpose of pressure compensation. The large areas exposed to pressure allow thehousing 38 to transmit balancing fluid more quickly and to thus support quicker pressure compensation. A variety ofseals 68, e.g. conventional shaft seals, may be disposed between thefirst component 22 andsecond component 24, as illustrated. The structure illustrated inFIG. 3 facilitates operation of the system with considerable pressure gradients acting across thebearing 48. As with the previous embodiment, the bearing 48 may be electrically isolated so that electrical signals can pass betweenelectrical contacts - In another embodiment,
housing 38 is a solid housing and seals 68 are used betweenfirst component 22 andsecond component 24, as illustrated inFIG. 4 . However, aporous element 70 is located inhousing 38 and extends throughhousing 38 betweencavity 56 andexterior region 60. Theporous element 70 is formed with a suitableporous material 62 so as to facilitate pressure equalization. As with previous embodiments, the pores ofporous material 62 may be filled withclean fluid 66. Theporous element 70 is sized properly so as to act as a clean fluid reservoir while remaining sealed at the interface with the surrounding portions ofhousing 38. - In another embodiment illustrated in
FIG. 5 ,housing 38 is again a solid housing and seals 68 are used betweenfirst component 22 andsecond component 24. However, theporous element 70 is located insecond component 24 and extends through thesecond component 24 betweencavity 56 andexterior region 60. By way of example, thesecond component 24 may be in the form ofshaft 40 andporous element 70 may be routed alongshaft 40 for exposure to bothcavity 56 andexterior region 60. In some applications, theentire shaft 40 may be formed fromporous material 62 so as to facilitate a greater rate of pressure equalization. In this latter embodiment, the pores ofporous material 62 also may be filled withclean fluid 60. In some applications, bothfirst component 22 and second component 24 (or portions of each of thecomponents 22, 24) may be formed of a suitableporous material 62. - Depending on the application,
system 20 may have a variety of configurations comprising other and/or additional components. For example, the shape and structure of thecomponents electrical coupler 28. Thesystem 20 also may utilize many types ofelectrical devices 30 for various downhole applications or other types of applications. Thebearing 48 may comprise a variety of plain bearings having conductive sliding contact surfaces or a variety of roller-type bearings having conductive rolling members, e.g. cylinders, balls, pins, or other suitable, conductive rolling contact elements. - Although a few embodiments of the disclosure have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.
Claims (20)
1. A system for use in a well, comprising:
a well string having a first component, a second component, and an electrical coupler for conducting electric current between the first component and the second component, the first component being rotatable with respect to the second component, the electrical coupler comprising:
a first electrical contact positioned in the first component;
a second electrical contact positioned in the second component;
a bearing formed of conductive material and mounted between the first component and the second component, the bearing being formed of a ii conductive material and being located in a cavity between the first component and the second component; and
a substantially incompressible fluid disposed in the cavity.
2. The system as recited in claim 1 , wherein pressure equalizes between the cavity and an exterior region outside of the cavity.
3. The system as recited in claim 2 , wherein the substantially incompressible fluid comprises a grease.
4. The system as recited in claim 3 , wherein the first component comprises a shaft.
5. The system as recited in claim 4 , wherein the bearing comprises a first race mounted against the first component in contact with the first electrical contact, a second race mounted against the second component in contact with the second electrical contact; and a plurality of conductive contact elements rotatably trapped s between the first race and the second race.
6. The system as recited in claim 2 , wherein the pressure equalizes through a porous gland material placed between the first component and the second component.
7. The system as recited in claim 6 , wherein the porous gland material contains a fluid.
8. The system as recited in claim 2 , wherein the pressure equalizes through a porous material located in at least one of the first component or the second component.
9. The system as recited in claim 2 , wherein the second component is formed of a porous material and further wherein the pressure equalizes through the porous material.
10. The system as recited in claim 2 , wherein the first component is formed of a porous material and further wherein the pressure equalizes through the porous material.
11. A method, comprising:
rotatably mounting a first component with respect to a second component;
locating a first electrical contact at the first component and a second electrical contact at the second component;
conductively connecting the first electrical contact and the second electrical contact via a conductive bearing; and
filling a volume around at least a portion of the conductive bearing with a substantially incompressible fluid.
12. The method as recited in claim 11 , wherein rotatably mounting comprises rotatably mounting first and second well components.
13. The method as recited in claim 12 , wherein conductively connecting comprises connecting via the conductive bearing by engaging a first race of the conductive bearing with the first component, engaging a second race of the conductive bearing with the second component, and rotatably capturing a plurality of the conductive rotatable members between the first race and the second race such that electricity may be conducted through the first race, the plurality of conductive rotatable members, and the second race.
14. The method as recited in claim 13 , wherein filling the volume comprises filling the volume with a grease.
15. The method as recited in claim 13 , further comprising equalizing pressure between an exterior region and the volume via a porous material.
16. The method as recited in claim 15 , further comprising using the porous material to prevent movement of particulates into the volume.
17. The method as recited in claim 12 , further comprising moving the first component and the second component downhole into a wellbore and removing heat generated by the ball bearing via flow of a well fluid.
18. A system for communicating electrical signals, comprising:
a first component rotatably mounted with respect to a second component;
a first electrical contact located at the first component and a second electrical contact located at the second component, the first electrical contact being operatively coupled with the second electrical contact via a conductive bearing, the conductive bearing having a plurality of rotatable members which rotate during rotation of the first component with respect to the second component; and
a housing creating a volume around at least a portion of the conductive bearing, the volume being filled with a substantially incompressible fluid.
19. The system as recited in claim 18 , wherein the first component and the second component are downhole well components.
20. The method as recited in claim 18 , wherein the conductive bearing comprises a first race engaged with the first component, a second race engaged with the second component, wherein the plurality of rotatable members are rotatably trapped between the first race and the second race such that electricity may be conducted through the first race, the plurality of rotatable members, and the second race.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US14/709,396 US20150368984A1 (en) | 2014-06-18 | 2015-05-11 | Pressure Compensated Rotating Electrical Contact |
PCT/US2015/031291 WO2015195251A1 (en) | 2014-06-18 | 2015-05-18 | Pressure compensated rotating electrical contact |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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US201462014086P | 2014-06-18 | 2014-06-18 | |
US14/709,396 US20150368984A1 (en) | 2014-06-18 | 2015-05-11 | Pressure Compensated Rotating Electrical Contact |
Publications (1)
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US20150368984A1 true US20150368984A1 (en) | 2015-12-24 |
Family
ID=54869196
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US14/709,396 Abandoned US20150368984A1 (en) | 2014-06-18 | 2015-05-11 | Pressure Compensated Rotating Electrical Contact |
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US (1) | US20150368984A1 (en) |
WO (1) | WO2015195251A1 (en) |
Citations (3)
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US2275538A (en) * | 1938-01-28 | 1942-03-10 | Gen Motors Corp | Lubricating system |
US6082470A (en) * | 1997-06-10 | 2000-07-04 | Charles T. Webb | Directional drilling system and apparatus |
US20130056195A1 (en) * | 2011-09-07 | 2013-03-07 | Joachim Sihler | System and method for downhole electrical transmission |
Family Cites Families (5)
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JP2001200838A (en) * | 1999-11-09 | 2001-07-27 | Seiko Instruments Inc | Fluid dynamic pressure bearing, fluid dynamic pressure bearing device, manufacturing method of fluid dynamic pressure bearing, and bearing surface machining method |
KR100517086B1 (en) * | 2004-07-29 | 2005-09-26 | (주)지엔더블유테크놀러지 | A fluid dynamic bearing motor having a cone bearing |
US8336632B2 (en) * | 2009-09-02 | 2012-12-25 | Harrier Technologies, Inc. | System and method for direct drive pump |
US20120224985A1 (en) * | 2011-03-02 | 2012-09-06 | Baker Hughes Incorporated | Electric submersible pump floating ring bearing and method to assemble same |
US8851864B2 (en) * | 2011-09-02 | 2014-10-07 | Baker Hughes Incorporated | Attenuating vibration in a submersible pump |
-
2015
- 2015-05-11 US US14/709,396 patent/US20150368984A1/en not_active Abandoned
- 2015-05-18 WO PCT/US2015/031291 patent/WO2015195251A1/en active Application Filing
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2275538A (en) * | 1938-01-28 | 1942-03-10 | Gen Motors Corp | Lubricating system |
US6082470A (en) * | 1997-06-10 | 2000-07-04 | Charles T. Webb | Directional drilling system and apparatus |
US20130056195A1 (en) * | 2011-09-07 | 2013-03-07 | Joachim Sihler | System and method for downhole electrical transmission |
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WO2015195251A1 (en) | 2015-12-23 |
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