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Publication numberUS20080078965 A1
Publication typeApplication
Application numberUS 11/859,861
Publication dateApr 3, 2008
Filing dateSep 24, 2007
Priority dateSep 28, 2006
Publication number11859861, 859861, US 2008/0078965 A1, US 2008/078965 A1, US 20080078965 A1, US 20080078965A1, US 2008078965 A1, US 2008078965A1, US-A1-20080078965, US-A1-2008078965, US2008/0078965A1, US2008/078965A1, US20080078965 A1, US20080078965A1, US2008078965 A1, US2008078965A1
InventorsWilliam Lane, Andrew Hanson
Original AssigneeWeatherford/Lamb, Inc.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Blowout preventer and pump rod clamp
US 20080078965 A1
Abstract
Disclosed herein is a combined pump rod clamp/BOP for use in a wellbore. The pump rod clamp/BOP is capable of supporting the weight of the pump rod, preventing axial or rotational movement of the rod, and simultaneous preventing fluids from escaping from the well, while maintaining electrical conductivity between the BOP and the polish rod. The pump rod clamp/BOP features rams having an arcuate channel for clamping a pump rod. The rams include a gripping non-metallic material non-releasably disposed on the engaging face of the ram. The non-metallic material can coat the entire engaging face of the ram, the arcuate channel only, or part of the arcuate channel. The non-metallic gripping material prevents the rams from damaging the pump rod when they engage the rod.
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Claims(17)
1. A pump rod clamp/blowout preventer for use in a well, comprising:
a housing having a bore for receiving a pump rod;
rams situated in the housing and movable between an activated position wherein the rams grippingly engage the pump rod with adequate force to support the pump rod and to prevent axial or rotational movement of the pump rod and prevent fluids from escaping from the well through the bore; the rams comprising:
an engaging face having an arcuate channel situated to receive the pump rod when the ram is the activated position, and
a non-metallic material non-releasably disposed on at least a portion of the engaging face for contacting the pump rod.
2. The pump rod clamp/blowout preventer of claim 1, wherein the non-metallic material covers the entire engaging face.
3. The pump rod clamp/blowout preventer of claim 1, wherein the non-metallic material is disposed substantially only in the arcuate channel.
4. The pump rod clamp/blowout preventer of claim 1, wherein the non-metallic material is disposed as one or more bands in the arcuate channel.
5. The pump rod clamp/blowout preventer of claim 1, wherein the non-metallic material is selected from the group consisting of elastomers, rubbers, polymers, ceramics, carbides, nitrides, metal oxides, chrysotile materials, metal oxides, and composites containing metal oxides.
6. The pump rod clamp/blowout preventer of claim 5, wherein the non-metallic material is aluminum oxide.
7. The pump rod clamp/blowout preventer of claim 1, wherein the non-metallic material is non-releasably affixed to the engaging face by gluing, brazing, form fitting, press fitting, molding, interference fitting, spray coating, or direct chemical deposition.
8. The pump rod clamp/blowout preventer of claim 1, wherein the arcuate channel includes one or more pockets for non-releasably receiving a band of the non-metallic material.
9. A pump rod clamp/blowout preventer for use in a well, comprising:
a housing comprising:
a longitudinal bore for receiving a pump rod;
at least one of an upper or lower flange for securing the housing to wellhead equipment; and
a pair of opposed radial bores generally perpendicular to, and terminating at, the longitudinal bore;
rams and a actuators received in each of the opposed radial bores, the actuators configured to move the rams between an activated and a non-activated position wherein in the activated position the rams grippingly engage the pump rod with adequate force to support the pump rod and to prevent axial or rotational movement of the pump rod and simultaneously prevent fluids from escaping from the well through the longitudinal bore, the rams comprising:
an engaging face having an arcuate channel situated to receive the pump rod when the ram is the activated position, and
a non-metallic material non-releasably disposed on at least a portion of the engaging face for contacting the pump rod.
10. The pump rod clamp/blowout preventer of claim 9, wherein the actuators comprise stems threadably received within the actuators such that rotation of the stems moves the rams between the activated and non-activated positions.
11. The pump rod clamp/blowout preventer of claim 9, wherein the non-metallic material covers the entire engaging face.
12. The pump rod clamp/blowout preventer of claim 9, wherein the non-metallic material is disposed substantially only in the arcuate channel.
13. The pump rod clamp/blowout preventer of claim 9, wherein the non-metallic material is disposed as one or more bands in the arcuate channel.
14. The pump rod clamp/blowout preventer of claim 9, wherein the non-metallic material is selected from the group consisting of elastomers, rubbers, polymers, ceramics, carbides, nitrides, metal oxides, chrysotile materials, metal oxides, and composites containing metal oxides.
15. The pump rod clamp/blowout preventer of claim 14, wherein the non-metallic material is aluminum oxide.
16. The pump rod clamp/blowout preventer of claim 9, wherein the non-metallic material does not provide an electrically insulating barrier between the pump rod and the ram.
17. The pump rod clamp/blowout preventer of claim 16, further comprising an electrical contact for maintaining electrical equilibrium between the housing and the pump rod.
Description
    CROSS-REFERENCE TO RELATED APPLICATIONS
  • [0001]
    This application claims priority to Provisional Application Ser. No. 60/827,319, filed Sep. 28, 2006, the entire contents of which are incorporated herein by reference.
  • FIELD OF THE INVENTION
  • [0002]
    This invention relates generally to oil and/or gas production and more specifically to a combination pump rod clamp and blowout preventer (BOP) for oil, gas, or water wells, and in particular to a pump rod clamp/blowout preventer having a pump rod clamping or gripping capability sufficient to support a pump rod and providing enhanced safety from static charge buildup.
  • BACKGROUND
  • [0003]
    Blowout preventers (BOPs) and pump rod clamps (aka polished rod clamps) have been generally known in the art for some time. Pump rod clamps are used to suspend the rod within the well, and/or to prevent rotational movement of the pump rod. Many types of pump rod clamps are known. Some rod clamps use a pair of rams that are driven radially inward to contact the pump rod and hold it in place. Others use wedges inserted around the rod. Still others use a pair of rams that can be bolted around the exterior surface of the rod and hung from a mandrel or other support member.
  • [0004]
    BOPs are used to seal off the well and contain its contents under a variety of different situations. For example, during the servicing of a wellhead one or more blowout preventers are often used to seal against the pump or polished rod to contain the contents of the well when downstream equipment is removed or disassembled for servicing. In other instances blowout preventers may be used to seal off a well where the pump rod is removed, or in the event of a failure of the pump rod. Blowout preventers typically include a pair of rams that are received within cylinders extending through a BOP housing and situated generally perpendicular to the longitudinal axis of the well casing. Typically the end of each ram has a semi-circular channel on its face to allow it to seal against the exterior surface of the pump rod when the BOP is actuated by driving the rams inward. The faces of the rams may include an elastomer or other sealing mechanism to ensure that a fluid tight seal is created when the rams fully engage the pump rod.
  • [0005]
    Generally, BOPs and pump rod clamps are separate pieces of equipment. The BOP is typically capable of sealingly engaging the pump rod to prevent blow out, but does not engage the rod forcefully enough to suspend the rod or prevent the rod from rotating. Thus a rod clamp is required for this duty. Likewise, though rod clamps grip the rod forcefully enough to suspend the rod or prevent its rotation, the engagement between the rod clamp and the rod is not typically a sealing engagement and thus does not prevent the contents of the well from escaping. Thus, there is a need for a single piece of equipment that can serve double-duty as both a pump rod clamp and a BOP.
  • [0006]
    Recent disclosures have purported to describe particular embodiments of combination BOP/well rod clamp devices. One example is U.S. Pat. No. 7,000,888, by Wright et al., (“the '888 patent”) the entire contents of which are incorporated herein by reference. The '888 patent describes a pump rod clamp having rams featuring arcuate channels to sealingly engage a pump rod. The rams include one or more gripping inserts releasably secured to the rams, or a non-metallic coating applied to the rams, providing an electrically insulating barrier between the pump rod clamp and the pump rod.
  • [0007]
    U.S. Pat. No. 6,843,313, by Hult (“the '313 patent”) and related U.S. Patent Application Publication No. 2005/0045323 A1, describe a pump drive head for a progressing cavity pump that includes a pump rod lock-out clamp that is integral with or adjacent to a blow-out-preventer. One embodiment described in these references includes a BOP that serves as a lock out clamp for well servicing. The BOP/lock-out clamp includes metal pistons that are forced against the pump rod to grippingly engage in metal-to-metal contact. The inner end of the pistons includes an arcuate recess with curvature corresponding to the pump rod. The pistons also include a narrow elastomeric seal running across the vertical flat face of the piston, along the arcuate recess, along the mid height of the piston and then circumferentially around the piston. The elastomeric seals seal between the pistons, between the pistons and the pump rod, and between the pistons and the piston bores, thereby preventing fluid from escaping up the well bore when the pistons are engaged with the pump rod. The entire contents of the '313 patent and U.S. Patent Application Publication No. 2005/0045323 A1 are incorporated herein by reference.
  • SUMMARY
  • [0008]
    Disclosed herein is a combination pump rod clamp/BOP. The pump rod clamp/BOP has a housing having a lateral bore for receiving a pump rod. Rams are contained in the housing for engaging the pump rod with strength capable of supporting the weight of the pump rod and preventing axial or rotational movement of the rod. When the pump rod clamp/BOP is activated, i.e., when the rams are engaged with the pump rod, the rams also seal off the lateral bore, preventing fluids from escaping from the well through the bore.
  • [0009]
    The rams have an arcuate channel for clamping the pump rod and also include a gripping non-metallic material non-releasably disposed on the face of the ram. The non-metallic material can coat the entire leading face of the ram, the arcuate channel only, or part of the arcuate channel. These and other features will be apparent in view of the below description and the attached drawings.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0010]
    FIG. 1A illustrates a pump rod clamp/BOP in a deactivated position.
  • [0011]
    FIG. 1B illustrates a pump rod clamp/BOP in an engaged (activated) position.
  • [0012]
    FIG. 2 illustrates a ram for a pump rod clamp/BOP, the ram having a non-metallic gripping material non-releasably disposed thereon.
  • [0013]
    FIG. 3 illustrates a top-down view of rams engaging a pump rod, as when a pump rod clamp/BOP is in an activated position.
  • [0014]
    FIG. 4 illustrates a ram for pump rod clamp/BOP having a non-metallic non-releasable insert.
  • DESCRIPTION
  • [0015]
    In the FIGS. like numbers represent like elements. FIGS. 1A and 1B illustrate a BOP/pump rod clamp according to the present disclosure. Pump rod clamp/BOP 1 includes a central housing 2 having a longitudinal bore 3 extending through the central housing 2 for receiving a pump rod 4. Central housing 2 may contain upper and lower flanges or threaded connections, 5 and 6 respectively, for mounting the housing to wellhead equipment. As is common with most blowout preventers, central housing 2 further includes a pair of opposed radial bores 7 and 8 that are generally perpendicular to, and that terminate at, longitudinal bore 3. Rams 9 and 10 are slidably received within bores 7 and 8. One or more actuators 11 are used to move rams 9 and 10 between a deactivated position FIG. 1A wherein rams 9 and 10 do not engage the exterior surface of the pump rod and an activated position wherein rams 9 and 10 extend into longitudinal bore 7 and 8 and grippingly engage the exterior surface of the pump rod 4. Any of a variety of actuators may be used to move the rams between their activated and deactivated positions. Such mechanisms include manual, hydraulic, pneumatic, or electric actuators. In the embodiment shown, actuators 11 include stems 12 that can be threadably received within the actuators. The inner most ends of the stems 12 are attached to rams 9 and 10 and are free to rotate with respect to the rams. Stems 12 can be rotated manually, electrically, pneumatically, or the like to move rams 9 and 10 between engaged and disengaged positions.
  • [0016]
    FIG. 2 illustrates a ram 9, having a engaging face 21 directed generally toward longitudinal bore 3 (and hence toward the exterior surface of a pump rod received within the longitudinal bore). Leading face 21 includes an arcuate channel 22 in general alignment with longitudinal bore 3 and a pump rod received therein. Arcuate channel 22 is positioned in such a manner that, when the rams are moved inwardly to their activated position, arcuate channel 22 encompasses the pump rod and grippingly engages the exterior surface of the rod.
  • [0017]
    Engaging face 21 includes a non-releasable non-metallic material 23 for making contact with the pump rod to securely hold the rod in place when the rams are moved to their activated position. FIG. 3 illustrates a top-down cross sectional view of rams 9 and 10 engaging a pump rod 4. Non-metallic material 23 makes contact with pump rod 4 and holds the rod in place. Leading faces 21 sealingly engage each other, thereby preventing fluids from escaping up bore 3. The non-metallic gripping material can be disposed only (or substantially only) in the arcuate channel as shown in FIG. 2 or can partially or totally coat the entire leading face 21.
  • [0018]
    FIG. 4 illustrates an alternative embodiment of ram 9 including gripping inserts 41 disposed in arcuate channel 22. Gripping inserts 41 can be made of any suitable non-metallic material, as described above. Gripping inserts 41 are joined to ram 9 using any suitable non-releasable method. For example, gripping inserts 41 can be non-releasably press-fit into receiving cavities machined into arcuate channel 22.
  • [0019]
    The non-metallic material can be any non-metallic material suitable for grippingly engaging a pump rod. The non-metallic material presents a hard surface for engaging the exterior of the pump rod without scoring or galling the rod. Traditional rod clamps that permit metal-to-metal contact often gall the surface of the rod and create burs, ridges, and other marks that can rip or tear packing material when the rod is pulled from the well. The non-metallic material reduces the likelihood of damage to the exterior of the rod. The non-metallic material can have a slightly roughened texture. As used herein, non-metallic material refers to materials that are not metals or alloys.
  • [0020]
    Suitable non-metallic materials include elastomers such as rubbers, polymers, and the like, ceramics, carbides, nitrides, composites, metal oxides, etc. Composites commonly used for automobile break shoes are particularly suitable. Such materials include chrysotile materials, metal oxides, and composites containing metal oxides. Metal oxides, such as aluminum oxide are also particularly suitable.
  • [0021]
    The non-metallic material can be affixed to the rams by any suitable non-releasable method. For example, the material can be glued to the ram using a durable gluing material such as a resin, epoxy, or the like. If the non-metallic material is amenable to brazing, as in the case of carbides, for example, brazing can be used. Non-releasably form fitting, press fitting, molding, or interference fitting can also be used. The non-metallic material can be deposited directly on the ram, spray coated onto the ram, or deposited chemically onto the ram, etc. According to one embodiment, the arcuate channel includes pockets for receiving a band of the non-metallic material. The non-metallic material can be press fit, or otherwise non-releasably disposed within the pockets, as shown in FIG. 4. Generally the methods of applying the non-metallic material to the rams in a non-releasable manner provide a high degree of rigidity in the structure.
  • [0022]
    The non-metallic material may or may not provide an insulating barrier between the rams and the pump rod and/or between the pump rod and the pump rod clamp/BOP. According to one embodiment, the non-metallic material does not provide such electrical insulation. In such an embodiment, the pump rod and the pump rod clamp/BOP may be maintained in electrical equilibrium (i.e., electrical contact is provided between the pump rod clamp/BOP and the pump rod) to prevent static charge buildup between the pump rod and the pump rod clamp/BOP. Such electrical equilibrium may be provided by a shunt wire, Conductive coatins, conductive seals, one or more metallic tabs, non-grippingly engaging metallic round nose spring plunger, or the like to maintain electrical equilibrium between the pump rod and the housing of the pump rod clamp/BOP.
  • [0023]
    It should be understood that the inventive concepts disclosed herein are capable of many modifications. To the extent such modifications fall within the scope of the appended claims and their equivalents, they are intended to be covered by this patent.
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US8128332Oct 27, 2008Mar 6, 2012T & T Engineering Services, Inc.Header structure for a pipe handling apparatus
US8192128May 20, 2009Jun 5, 2012T&T Engineering Services, Inc.Alignment apparatus and method for a boom of a pipe handling system
US8192129May 27, 2010Jun 5, 2012T&T Engineering Services, Inc.Pipe handling boom pretensioning apparatus
US8371790Mar 12, 2009Feb 12, 2013T&T Engineering Services, Inc.Derrickless tubular servicing system and method
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US8469648Oct 27, 2008Jun 25, 2013T&T Engineering ServicesApparatus and method for pre-loading of a main rotating structural member
US8474806Jan 26, 2009Jul 2, 2013T&T Engineering Services, Inc.Pipe gripping apparatus
US8496238Feb 14, 2009Jul 30, 2013T&T Engineering Services, Inc.Tubular gripping apparatus with locking mechanism
US8646522Sep 6, 2011Feb 11, 2014T&T Engineering Services, Inc.Method of gripping a tubular with a tubular gripping mechanism
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US8905699Jun 5, 2012Dec 9, 2014T&T Engineering Services, Inc.Alignment apparatus and method for a boom of a pipe handling system
US9234400 *Mar 8, 2012Jan 12, 2016Subsea 7 LimitedSubsea pump system
US9500049Apr 2, 2013Nov 22, 2016Schlumberger Technology CorporationGrip and vertical stab apparatus and method
US9556689Dec 9, 2014Jan 31, 2017Schlumberger Technology CorporationAlignment apparatus and method for a boom of a pipe handling system
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US20100296899 *May 20, 2009Nov 25, 2010T&T Engineering ServicesAlignment apparatus and method for a boom of a pipe handling system
US20140124211 *Mar 8, 2012May 8, 2014Roger Warnock, JR.Pump system
US20160145955 *Feb 1, 2016May 26, 2016Netzsch Pumpen & Systeme GmbhClamping Device And Method For Fixing A Drive Shaft In A Stationary Manner
CN104625597A *Nov 15, 2013May 20, 2015中国石油天然气股份有限公司Oil pumping unit hair pigtail lead head machining and manufacturing method and device
WO2010085803A2 *Jan 26, 2010Jul 29, 2010T&T Engineering ServicesPipe gripping apparatus
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WO2017011297A1 *Jul 8, 2016Jan 19, 2017Ge Oil & Gas Pressure Control LpAdjustable lock-out ram for production bop applications
Classifications
U.S. Classification251/1.3
International ClassificationE21B7/00
Cooperative ClassificationE21B19/12, E21B33/062
European ClassificationE21B33/06B2, E21B19/12
Legal Events
DateCodeEventDescription
Sep 24, 2007ASAssignment
Owner name: WEATHERFORD/LAMB, INC., TEXAS
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LANE, WILLIAM C.;HANSON, ANDREW J.;REEL/FRAME:019866/0001
Effective date: 20070921