Inflatable Packer Patents (Class 277/331)
  • Patent number: 11906048
    Abstract: A sufficient sealing property of a through hole is ensured. A sealing structure includes a cylindrically-shaped body part inserted into the through hole, formed of a thin plate of a first thickness, one end of the body part being open and another end of the body part being closed, a tapered part connected to the opened one end of the body part and including a diameter gradually expanding outward as a distance from the body part increases, and a first bent part connected to the tapered part, formed of a thin plate thinner than the first thickness, and bent inward so that a protruding part protruding outward elastically abuts against an inner peripheral surface of the through hole.
    Type: Grant
    Filed: April 14, 2022
    Date of Patent: February 20, 2024
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, Newfrey LLC
    Inventors: Tomohiro Takenaga, Keisuke Uchida, Tatsuya Okamoto, Satoru Ando, Toshio Narita, Hiroshi Imaizumi, Naoki Yamaguchi
  • Patent number: 11851974
    Abstract: A resettable packer system for pumping operations includes an inflatable packer that expands between the resettable packer system and a tubing wall or a casing wall, thereby creating a seal in a well and a pump that inflates the inflatable packer at a desired depth within the well when activated. The resettable packer system further includes an inner sleeve that includes ports for a fluid to pass through, an outer sleeve that is connected to the pump and creates a sealed fluid chamber with the inflatable packer when ports of the outer sleeve and the ports of the inner sleeve are misaligned. In addition, the inner sleeve slides axially along an inner surface of the outer sleeve, thereby aligning or misaligning the ports of the outer sleeve with the ports of the inner sleeve. Further, the inflatable packer contracts when the pump is inactive.
    Type: Grant
    Filed: August 26, 2022
    Date of Patent: December 26, 2023
    Assignee: SAUDI ARABIAN OIL COMPANY
    Inventor: Chidirim Enoch Ejim
  • Patent number: 11674387
    Abstract: The disclosure relates to a method of evaluating characteristics of an earth formation, comprising deploying a packer assembly in a borehole penetrating an earth formation, the packer assembly comprising an instrumented inflatable packer element including fiber optic sensors; inflating the instrumented inflatable packer elements; detecting, using the fiber optic sensors, events occurring in the earth formation; and transmitting data corresponding to the detected events to a surface processing system. The disclosure also relates to a packer element and a instrumented packer assembly system. The disclosure may enable to derive formation characteristic in several configurations such as a stress test or a hydraulic fracturing configuration.
    Type: Grant
    Filed: February 22, 2021
    Date of Patent: June 13, 2023
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Hugues Dupont, Thomas Berard, Colin Allan Wilson, Pierre-Yves Corre
  • Patent number: 10961807
    Abstract: Methods and systems for isolating a loss circulation zone of a subterranean formation includes lowering a drill string having a tubular member from a surface into a subterranean well and securing a packer assembly to the tubular member, the packer assembly having an inflatable packer unit and a protective sleeve. The protective sleeve is in an extended position and circumscribes the inflatable packer unit and the inflatable packer unit is in a deflated condition. A stabilizer body is secured to the tubular member downhole of the packer assembly. The stabilizer body is shaped to centralize the packer assembly and direct debris traveling uphole in a direction radially outward of the packer assembly. The protective sleeve is moved from the extended position to a retracted position. The inflatable packer unit is inflated to an inflated condition, forming a seal with an inner diameter surface of the subterranean uphole of the loss circulation zone.
    Type: Grant
    Filed: February 12, 2018
    Date of Patent: March 30, 2021
    Assignee: SAUDI ARABIAN OIL COMPANY
    Inventors: Herschel Foster, Ossama R. Sehsah, Mahmoud Alqurashi
  • Patent number: 10844686
    Abstract: An annular barrier is expandable in an annulus between a well tubular structure and an inside wall of a borehole downhole for providing zone isolation between a first zone and a second zone of the borehole. The annular barrier has a tubular part for mounting as part of the well tubular structure, an expandable metal sleeve surrounding the tubular part and having an inner face facing the tubular part and an outer face facing towards the inside wall of the borehole, each end of the expandable metal sleeve being connected with a connection part which is connected with the tubular part, a space between the inner face of the expandable metal sleeve and the tubular part, and an expansion opening in the tubular part through which fluid may enter into the space in order to expand the expandable metal sleeve.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: November 24, 2020
    Assignee: Welltec Oilfield Solutions AG
    Inventors: Jørgen Hallundbæk, Ricardo Reves Vasques
  • Patent number: 10480290
    Abstract: A controller for operating a downhole tool includes a tubular body; a seat disposed in the body for receiving first and second pump-down plugs, at least a portion of one of the seat and the plugs being radially displaceable to pass through or allow passage of the other at a first threshold pressure differential; a catcher located below the seat for receiving the plugs after passing through the seat; a toggle linked to the seat to alternate between a locked position and an unlocked position in response to seating of the plugs; and a control mandrel for engaging a piston of the downhole tool and linked to the toggle: to be longitudinally movable between a first position and a second position when the toggle is unlocked, and to be prevented from movement from the first position to the second position when the toggle is locked.
    Type: Grant
    Filed: December 9, 2016
    Date of Patent: November 19, 2019
    Assignee: WEATHERFORD TECHNOLOGY HOLDINGS, LLC
    Inventors: Wei Jake Xu, Albert C. Odell, II
  • Patent number: 10337297
    Abstract: A method of injecting fluid into a formation, comprises exerting a mechanical force on a wall of a bore extending through a formation to modify the permeability of the formation; and injecting fluid into the modified formation. The mechanical force is exerted through inflation of at least one pressure deformable member mounted on a base member with a retaining ring.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: July 2, 2019
    Assignee: HALLIBURTON MANUFACTURING AND SERVICES LIMITED
    Inventors: Stephen Edmund Bruce, Stephen Kent, Dominic Patrick McCann, David Allan Noblett, David Grant
  • Patent number: 10281043
    Abstract: A carbon nanotube-based thermal gasket for space vehicle applications, and process for making the same, is disclosed. A thermal gasket is created that includes one or more free-standing carbon nanotube (CNT) sheets formed of a CNT composition comprising randomly-oriented CNTs and a thermally-conductive resin material. The thermally-conductive resin material is encased within the one or more free-standing CNT sheets and prevented by the one or more CNT sheets from physical contact with an outer side of the thermal gasket.
    Type: Grant
    Filed: July 8, 2016
    Date of Patent: May 7, 2019
    Assignee: Lockheed Martin Corporation
    Inventors: Edward Allen Pierson, Edward Nathan Harris, Slade Havelock Gardner
  • Patent number: 9759036
    Abstract: A sealing device for a tubing arrangement, preferably for use in an offshore facility, such as an offshore wind turbine or an oil rig. The tubing arrangement has a cable or an inner tube arranged in an interior part thereof. The sealing device comprises a substantially rigid housing and a flexible plug part arranged in an interior part of the housing. The housing is mountable on or forms part of the tubing arrangement in such a manner that the interior part of the housing communicates with the interior part of the tubing arrangement. The flexible plug part comprises an inlet opening connectable to a grout source. When grout material is supplied to the flexible plug part, the flexible plug part expands, thereby providing sealing between the housing and a cable or inner tube arranged in the interior of the tubing arrangement. The sealing device can be mounted on the tubing arrangement before the tubing arrangement is mounted on an offshore facility, and the grout material can be supplied at a later time.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: September 12, 2017
    Assignee: MHI Vestas Offshore Wind A/S
    Inventor: Anders Søe-Jensen
  • Patent number: 9353606
    Abstract: A method of injecting fluid into a formation, comprises exerting a mechanical force on a wall of a bore extending through a formation to modify the permeability of the formation; and injecting fluid into the modified formation. The mechanical force may be exerted through inflation of at least one pressure deformable member mounted on a base member. The base member may be a base pipe. The pressure deformable member may be a hollow or tubular member mounted externally of the base pipe. A plurality of pressure deformable members are provided.
    Type: Grant
    Filed: November 16, 2011
    Date of Patent: May 31, 2016
    Assignee: Darcy Technologies Limited
    Inventors: Stephen Edmund Bruce, Stephen Kent, Dominic Patrick Joseph McCann, David Allan Noblett, David Grant
  • Patent number: 9334707
    Abstract: An emergency well plug apparatus that includes a drill string mating unit connectable endwise to an extant drill string, a top ring releasably attachable to the drill string mating unit, at least one support member attachable to the top ring, and additional support members attachable thereto, wherein sequential inflation of respective inflatable members disposed upon each support member effectively plugs a blowout preventer, wellhead, or well shaft, from gushing fluids and the drill string mating unit may be subseqeuntly retracted with the remainder of the apparatus in place.
    Type: Grant
    Filed: March 19, 2013
    Date of Patent: May 10, 2016
    Inventor: Roy L. Adger, Jr.
  • Patent number: 8894069
    Abstract: Inflatable packers are provided with one or more components to improve longevity and/or functionality. One or more of the packer components utilizes reinforced materials incorporated in a manner that enables the improved longevity and/or functionality.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: November 25, 2014
    Assignee: Schlumberger Technology Corporation
    Inventors: Zheng Rong Xu, Frank Espinosa, John R. Lovell, Pierre-Yves Corre, David Milton Eslinger
  • Patent number: 8807209
    Abstract: A swellable material seal includes a quantity of swellable material disposed in a geometric configuration; and a plurality of openings in the material to enhance wettability thereof by a swelling fluid.
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: August 19, 2014
    Assignee: Baker Hughes Incorporated
    Inventor: James G. King
  • Publication number: 20140219825
    Abstract: A thermal compensator for a motor seal, includes: a guide tube for receiving a shaft of the motor seal; a metallic bag disposed around the guide tube and having an expansion profile formed in at least a portion thereof to accommodate radial and circumferential expansion of the metallic bag; a pair of flanges attached to opposite ends of the metallic bag; and a pair of adapters fastened to the respective flanges and receiving respective ends of the guide tube.
    Type: Application
    Filed: February 6, 2014
    Publication date: August 7, 2014
    Applicant: OILFIELD EQUIPMENT DEVELOPMENT CENTER LIMITED
    Inventors: Enrique C. SANTOS, Edison R. MADAMBA
  • Patent number: 8479810
    Abstract: Downhole apparatus comprises a base pipe and a plurality of non-concentric pressure deformable chambers mounted externally on the pipe. The chambers may be inflated to increase the diameter of the apparatus and engage and support a surrounding bore wall.
    Type: Grant
    Filed: June 25, 2008
    Date of Patent: July 9, 2013
    Inventor: Paul David Metcalfe
  • Publication number: 20130043049
    Abstract: The invention relates to an apparatus for sealing off a part of a wall (5) in a section (6) drilled into an earth formation and to be placed in such section (6), where said apparatus comprises elongate members (1) arranged along a closed curve, where adjacent elongate members (1) are connected via intermediate links (2), each link (2) being moveable from an unlocked position to a locked position. The invention further relates to a method for applying such an apparatus comprising the steps of:—positioning an apparatus in collapsed configuration in a section (6) drilled into an earth formation with a the wall (5) to be sealed off;—expanding a net or cage in the apparatus, which net or cage is formed by elongate members (1) connected by intermediate links (2);—expanding a flexible member (3) arranged at an outer diameter of the apparatus to seal against the wall (5).
    Type: Application
    Filed: December 2, 2010
    Publication date: February 21, 2013
    Inventor: Wilhelmus Hubertus Paulus Maria Heijnen
  • Patent number: 8246052
    Abstract: A downhole submersible pumping system includes a housing and a bag seal assembly. The bag seal assembly includes a seal bag and a fastening assembly. The fastening assembly is configured to exert a compressive force between inner and outer surfaces of a first end of the seal bag. The fastening assembly may include a first ring attached to the support tube, a second ring and a plurality of fastening members. The first ring may be configured for threaded engagement with the support tube. The second ring is configured for engagement with the first ring.
    Type: Grant
    Filed: October 30, 2007
    Date of Patent: August 21, 2012
    Assignee: GE Oil & Gas ESP, Inc.
    Inventor: Robert L. Marvel, III
  • Patent number: 8202059
    Abstract: A system for pressurizing fluids is provided. The system includes a container with an open end and a closed end. The container contains the fluids to be pressurized. The system further includes a dynamic seal capable of expanding to facilitate sealing of the open end of the container. The system also includes a tube arrangement passing through the dynamic seal into the container. The tube arrangement facilitates passage of a first pressurizing medium to pressurize the fluids.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: June 19, 2012
    Inventor: Shervin Javadi
  • Publication number: 20120138315
    Abstract: A downhole seal (10) comprises an inflatable structure (14) which receives a volume of swellable particles (18) at a downhole location. The seal (10) is adapted to permit the swellable particles (18) to become exposed to an activator to initiate selling of said particles (18) to inflate the inflatable structure (14).
    Type: Application
    Filed: September 8, 2009
    Publication date: June 7, 2012
    Applicant: SWELLFIX B.V.
    Inventors: John Dewar, Arie Vliegenthart
  • Patent number: 7828054
    Abstract: A packer for temporarily closing a well or a pipe including a support and an inflatable tubular element attached to the support, the element having a wall of elastic material that is deformable radially outwards under the action of internal pressure so as to press hermetically against the wall of the well or pipe and is reinforced with multistrand metal cables embedded in the wall of the material, wherein the spaces between the strands forming the metal cables contain a fluid impermeable material so that fluid is unable to flow through the spaces of the cables.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: November 9, 2010
    Assignee: Schlumberger Technology Corporation
    Inventor: Jean-Louis Saltel
  • Publication number: 20100230902
    Abstract: Disclosed herein is a downhole sealing device. The device includes, a swellable member, and a passageway having a perimetrically continuous wall. The swellable member is configured to cause sealing between a downhole structure and a plurality of tubulars when in a swelled condition, the plurality of tubulars are routed through a plurality of voids extending longitudinally through the swellable member, each of the plurality of voids has perimetrically continuous walls surrounding each of the plurality of tubulars.
    Type: Application
    Filed: March 12, 2009
    Publication date: September 16, 2010
    Applicant: BAKER HUGHES INCORPORATED
    Inventors: Robert O. Castillo, Darwin D. Arline, Gregory C. Badke
  • Publication number: 20100038860
    Abstract: An inflatable sleeve or packer includes a mandrel that extends along a longitudinal axis and a sealed inflatable jacket which is connected to the mandrel and selectively adopts a rest configuration or a maximum inflation configuration. The sleeve also includes a restraining sheath which covers the inflatable jacket and is at least partially formed by essentially inextensible fibres including peripheral fibres which each extend around the longitudinal axis, the peripheral fibres adopting a pleated configuration for the rest configuration of the jacket and a stretched configuration for the maximum inflation configuration thereof.
    Type: Application
    Filed: December 17, 2007
    Publication date: February 18, 2010
    Inventor: Francis Cour
  • Patent number: 7441596
    Abstract: A sealing element that swells on exposure to well fluids present or added to the wellbore is assembled to the mandrel in a manner to induce circumferential stresses proximately to the inside diameter of the element so as to resist the tendency of the inside diameter of the element to grow during the swelling process. A vacuum and a pressure method are described. Leak paths between the mandrel and the sealing element are minimized or eliminated as a result.
    Type: Grant
    Filed: June 23, 2006
    Date of Patent: October 28, 2008
    Assignee: Baker Hughes Incorporated
    Inventors: Edward T. Wood, Steven N. Bailey, Walter J. Laflin, Vel Berzin, James R. Korte, Edward J. O'Malley, Bennett M. Richard
  • Patent number: 7363970
    Abstract: An integral bodied composite packer is constructed entirely of a composite material. It can include an expandable middle portion with an elastomeric cover to engage an exterior surface of a well bore. The expandable portion can include continuous strands of polymeric fibers to reinforce the body and prevent extrusion. The packer body can have longitudinal cuts or slats to provide rigidity of the body after expansion. The slats can overlap. The packer can include an elastomeric cover or layer therein to engage the well bore. The expandable portion can include a reinforcement member in a laminar portion of the body made from high strength alloys, fiber-reinforced polymers and/or elastomers, nanofiber, nanoparticle, and nanotube reinforced polymers and/or elastomers.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: April 29, 2008
    Assignee: Schlumberger Technology Corporation
    Inventors: Pierre-Yves Corre, Gilles Carree
  • Publication number: 20080042362
    Abstract: A downhole packer or sealing device uses a swelling sealing element that is initially held in a compressed state. Exposure to well or other fluids occurs downhole as the initial restraint on the element is overcome. The element takes on well fluids as it resumes its relaxed position or swells. The element is preferably an open cell material such as foam and has another material in its passages. The material in the passages, when exposed to well fluids, itself grows in size and can get harder. It blocks or seals the passages in the foam so that the swollen foam becomes more like a closed cell material and can retain a seal against a greater range of operating conditions than had its passages remained open or unobstructed with another material.
    Type: Application
    Filed: July 14, 2006
    Publication date: February 21, 2008
    Inventor: Edward T. Wood
  • Patent number: 7331581
    Abstract: Improved inflatable packers are provided. A packer may be constructed from hybrid structures including slat structures and weave structures. A packer may include a bladder and a cover, with a plurality of slats disposed therebetween, and/or a weave structure or anti-extrusion layer disposed therebetween. The slats may vary in width and thickness, and be provided with a plurality of reinforcement members. The reinforcement members may be longitudinally and/or transversely disposed in the slats. One or more of the various components of the packer preferably include a fiber, a wire, a cable, a nanofiber, a nanotube, and/or a nanoparticle modified elastomer. Anchors may be attached to or embedded in the outer cover. The packer may include a carcass having an end coupling including a plurality of slats. Improved packer cups are also disclosed, and preferably include a body member reinforced with a nanotube or similar material.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: February 19, 2008
    Assignee: Schlumberger Technology Corporation
    Inventors: Zheng Rong Xu, Frank Espinosa
  • Patent number: 7306033
    Abstract: An apparatus and method, particularly useful for isolating zones in a hydrocarbon wellbore. The apparatus includes a tubular section, such as a length of casing or liner tubular, arranged to be run into and secured within the wellbore which may be open hole or already cased. At least one sleeve member is positioned on the exterior of the tubular section and is sealed thereto. A pressure control device, which typically consists of a pressurised hydraulic fluid delivery device, can be used to increase the pressure within the sleeve member to cause the sleeve member to move outwardly and bear against an inner wall of the wellbore.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: December 11, 2007
    Assignee: Read Well Services Limited
    Inventor: Andrew John Gorrara
  • Patent number: 6948715
    Abstract: A seal assembly with an accumulator ring for protecting a seal from explosive decompression is disclosed. The accumulator ring and the seal are contained within a seal gland. The seal is made of a material that is susceptible to damage from explosive decompression. When exposed to a high-pressure fluid environment, the accumulator ring fills with a quantity of high-pressure fluid, either by permeation if it is solid or by permeation and/or vents and/or channels leading to a void if it is hollow. During an explosive decompression event, the accumulator ring expands to fill the remaining volume of the seal gland. Then, the accumulator ring exerts an axial compressive or supporting force on the seal for a sufficient amount of time to allow the seal to expel fluid contained in it and minimize the effects of explosive decompression thereto.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: September 27, 2005
    Assignee: Cooper Cameron Corporation
    Inventors: William M. Taylor, Gerald S. Baker, Larry E. McDonald
  • Publication number: 20040216870
    Abstract: The borehole closure (1) includes a supply line (2), which is made of plastic and includes a longitudinal passage, and an inflating tube (28). The supply line (2) has a feed end (3) with an external thread (4) and a discharge end (5) with an external thread (6) as well as an integrated non-return valve (18). The inflating tube (28) surrounds the supply line (2) in a sealing manner with its end portions (29, 30) at formation of an elongate annular chamber (33). Transverse passages (37) are provided in the wall (36) of the supply line (2) at the end of the annular chamber (33). The ports of the transverse channels (37) into the annular chamber (33) are covered by elastic sealing rings (39), which are guided through fixing rings (40), arranged on both sides of the sealing rings (39). A rupture disk (25) is fixed to the end surface of the discharge end (5) of the supply line (2) by means of a thrust ring (24) with an internal shearing edge as well as a threaded sleeve (7) with an internal radial shoulder (9).
    Type: Application
    Filed: January 15, 2004
    Publication date: November 4, 2004
    Inventor: Joachim Zotta
  • Patent number: 6779601
    Abstract: An inflatable packing element for a bridge plug. The packing element has an anchor portion and a sealing cover portion, each of which is expanded in order to engage and seal a surrounding string of casing or borehole. The anchor portion has a minimum length defined by 2.63× the inner diameter of the surrounding pipe or other wellbore opening. At the same time, the anchor portion has a maximum length defined by approximately 49% of the length of the expanded portion of the packing element engaging the surrounding pipe or other wellbore opening.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: August 24, 2004
    Assignee: Weatherford/Lamb, Inc.
    Inventors: Paul J. Wilson, Corey E. Hoffman
  • Patent number: 6595283
    Abstract: Extrusion resistant inflatable tool having a biaxially oriented woven material disposed about at least one elastomeric element of the inflatable tool and radially inwardly of a rib structure of the inflatable tool. The woven material prevents extrusion of the elastomeric element between individual ribs of the ribs structure during the inflation of the tool.
    Type: Grant
    Filed: July 19, 2000
    Date of Patent: July 22, 2003
    Assignee: Baker Hughes Incorporated
    Inventors: Rocky A. Turley, Yusheng Yuan
  • Patent number: 6290231
    Abstract: A diverter body having an upper portion, a central portion and a lower portion is secured to the upper end of a riser and lands in a housing. The central portion has lateral flow openings that axially align with a lateral flowline outlet in the housing. A pair of identical gallery seals locate above and below the lateral flowline outlet. The upper gallery seal is located between the upper portion, the central portion and the housing. The upper gallery seal has upper and lower metal rings and a central elastomer sandwiched therebetween. An outer diameter of the elastomer seals against the housing bore. The rings are symmetric and are mated to the elastomer along interfaces which are S-shaped in cross-section to form shoulders. The shoulders face radially inward. An annular cavity and a pair of flexible annular lips are formed along the inner diameter portion of the elastomer. A passage extends through the diverter bodies and communicates with the cavity.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: September 18, 2001
    Assignee: Abb Vetco Gray, Inc.
    Inventors: Donald R. Petrash, Richard W. Slyker
  • Patent number: 6041858
    Abstract: An expandable apparatus for sealing a space downhole in a wellbore. The apparatus has an expandable body having a hollow interior for defining an open flow path. A deformable material within the hollow body interior partially obstructs the flow path when the body is run into the wellbore, and the deformable material is displaceable to expand the body into the downhole space and to open the body flow path. Such material can be displaced with a setting tool or with mechanical movement of the body components. A second body section can be moved relative to a first body section to displace the deformable material from the body interior. The second body section can initially be discontinuous with the first body section to permit installation through narrow wellbore spaces and can be connected downhole to create a unitary body structure.
    Type: Grant
    Filed: September 27, 1997
    Date of Patent: March 28, 2000
    Assignee: PES, Inc.
    Inventor: Napoleon Arizmendi
  • Patent number: 6009951
    Abstract: An inflatable packer having a sealing section, with noncontinuous ribs, is provided in combination with a ribbed element, which provides anchoring capabilities in tandem with the partially ribbed element which provides sealing capabilities in downhole applications.
    Type: Grant
    Filed: December 12, 1997
    Date of Patent: January 4, 2000
    Assignee: Baker Hughes Incorporated
    Inventors: Martin Paul Coronado, Rustom Khodadad Mody, Mark C. Solari
  • Patent number: 5924743
    Abstract: The invention concerns a device adapted to be fixed and sealed to at least one cylindrical member (1, 1'), characterized in that it includes:a first sleeve (2),a second sleeve (3) coaxial with the first sleeve (2) having a greater capacity for deformation than the first sleeve (2) and fixed and sealed to the first sleeve (2) at both ends,at least two cylindrical rings (4, 5) coaxial with the second sleeve (3), pressed against the latter and each fixed by one edge to one end of the second sleeve (3), andmeans (6, 6') for injecting a pressurized fluid between the first sleeve (2) and the second sleeve (3).
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: July 20, 1999
    Assignees: Gec Alsthom Stein Industrie, Central Nuclearie Europeene, Electricite De France
    Inventors: Michel Bonmartin, Bruno Veyrat, Yann Wolff, Christian Bonnand