US3485056A - Sealing system for underwater installation - Google Patents

Sealing system for underwater installation Download PDF

Info

Publication number
US3485056A
US3485056A US760807A US3485056DA US3485056A US 3485056 A US3485056 A US 3485056A US 760807 A US760807 A US 760807A US 3485056D A US3485056D A US 3485056DA US 3485056 A US3485056 A US 3485056A
Authority
US
United States
Prior art keywords
capsule
seal
cellar
compartment
metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US760807A
Other languages
English (en)
Inventor
Sydney S Helmus
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Canocean Resources Ltd
Original Assignee
Lockheed Aircraft Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lockheed Aircraft Corp filed Critical Lockheed Aircraft Corp
Application granted granted Critical
Publication of US3485056A publication Critical patent/US3485056A/en
Assigned to CANOCEAN RESOURCES LTD. reassignment CANOCEAN RESOURCES LTD. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE 3-5-80 Assignors: LOCKHEED PETROLEUM SERVICES LTD.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B41/00—Equipment or details not covered by groups E21B15/00 - E21B40/00
    • E21B41/06—Work chambers for underwater operations, e.g. temporarily connected to well heads
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/02—Sealings between relatively-stationary surfaces
    • F16J15/06—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces
    • F16J15/062—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces characterised by the geometry of the seat
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/02—Sealings between relatively-stationary surfaces
    • F16J15/06—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces
    • F16J15/10—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with non-metallic packing
    • F16J15/104—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with non-metallic packing characterised by structure
    • F16J15/106—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with non-metallic packing characterised by structure homogeneous
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B33/00—Sealing or packing boreholes or wells
    • E21B33/02—Surface sealing or packing
    • E21B33/03—Well heads; Setting-up thereof
    • E21B33/035—Well heads; Setting-up thereof specially adapted for underwater installations
    • E21B33/037—Protective housings therefor

Definitions

  • This invention relates to a method and apparatus for making a fluidtight connection between an underwater installation and a submersible capsule.
  • the underwater installation might be of any type used in mining or other deep sea exploration and production activities. However, for purposes of this description, the underwater installation will be referred to as a wellhead celler of the type considered for use in the petroleum industry.
  • the submersible capsule may likewise take a variety of forms but for purposes of the present description the capsule is of the type having means for providing an atmospheric environment so that personnel may perform operations at the wellhead cellar after the capsule has been moved into fiuidtight engagement therewith.
  • the invention is especially adapted to deep water installations situated at depths beyond which a diver can safely and readily work, for example, depths below approximately 300 feet.
  • the sealing system of the present invention should preferably be capable of operation in water depths extending to approximately 1,000 feet or greater.
  • sealing system to which the invention is directed should be capable of functioning even though the mating surfaces between the capsule and underwater installation are gouged or somewhat fouled with rust scale and marine growth, etc.
  • the sealing system is an extremely important facet of the subject deep water operations because failure of the seal could result in loss of life to the personnel performing the underwater operations.
  • An advantage of the present invention is the provision of a seal system which utilizes ambient water pressure to both establish and maintain a fluidtight seal between the submersible capsule and the underwater installation.
  • a further advantage of the invention is the provision of a double sealing arrangement comprised of a metal-tometal face type seal which is backed up by a resilient seal element which forms an O-ring type seal at the radially outer edge of the metal-to-metal seal.
  • FIG. 1 is a diagrammatic view illustrating an exemplary method by which a submersible capsule may be lowered down toward an underwater installation;
  • FIG. 2 is a longitudinal view, partially in section, illustrating certain details of the submersible capsule and the underwater installation;
  • FIG. 3 is a sectional view illustrating details of the seal assembly just prior to initial engagement of the submersible capsule with the underwater installation.
  • FIG. 4 is a sectional view illustrating details of the seal assembly after the submersible capsule and the underwater installation have been engaged in fluidtight relation.
  • FIG. 1 of the drawing there is illustrated an exemplary application of the invention in use in a body of water 21.
  • an opera-ting station taking the form of a floating barge 23 is shown floating on the surface of the water 21 in a position approximately above a preselected underwater installation such as a wellhead cellar 25.
  • a submersible capsule 27 is being moved downwardly toward the wellhead cellar 25.
  • the capsule 27 is divided into an upper compartment 29 and a lower compartment 31.
  • the compartment 29 provides an atmospheric environment for one or more human personnel who will perform various operations at the wellhead cellar 25.
  • a conduit package 33 is connected between the surface station 23 and the submersible capsule 27.
  • the conduit package 33 contains air lines, conduits for electrical conductors and conduits for hydraulic connetions.
  • a cable 35 extends between the wellhead cellar 25 and the submersible capsule 27.
  • the lower compartment 31 of the capsule 27 is provided with a winch or cable reeling mechanism 37.
  • the capsule is caused to descend downwardly into engagement with the wellhead cellar 25 by winding up the cable 35 on the winch mechanism 37.
  • the lowermost end of the capsule 27 is provided with a flared skirt 41 which facilitates in guiding the capsule down onto an upwardly projecting annular probe 43 formed on the top of the wellhead cellar 25.
  • annular protuberance or shoulder 45 is formed on the very top of the probe 43.
  • -angled wall member 47 extends downwardly from the shoulder 45 until it meets a cylindrical outer wall 49 formed on the outer surface of the probe 43.
  • annular inner wall 51 Just above the flared skirt or mouth 41 of the capsule 27 there is formed an annular inner wall 51.
  • annular wall 51 of the capsule 27 extends upwardly to a point where it intersects an internal shoulder 53.
  • a resilient annular seal element '55 is securely positioned such as by ce- 3 ment or mechanical fasteners such as the shouldered shear ledge 57 shown in FIG. 4.
  • FIG. 3 the capsule 27 is shown just after the flared mouth 41 thereof has been guidingly received on the probe 43 of the wellhead cellar 25.
  • the capsule 27 has been aligned upon the probe 43 but the lower compartment 31 of the capsule is still in communication with the ambient sea water which flows through the annular space X between the surfaces 49 and 51.
  • a lower corner portion 59 of the seal will contact the angled surface 47 formed on the cellar probe 43.
  • a fluidtight seal will be formed preventing sea water from flowing into or out of the lower compartment 31 of the capsule 27.
  • the capsule 27 is provided with a main conduit 61 which is preferably provided with a flexible lower end which terminates in the vicinity of the bottom portion of the flared mouth 41.
  • the conduit 61 is provided with a first branch conduit 62 which communicates through a valve 64 which when open will allow sea water to flow into or out of the conduit 62.
  • a second branch conduit 64 leads from the main conduit 61 into the atmospheric upper compartment 29 of the capsule 27.
  • the conduit 65 is also provided with a valve 67.
  • the valve 67 communicates fluid from the conduit 65 to a sump or drain 69 which may in turn be connected through a conduit not shown to the sea water outside the capsule 27 for purposes of overboard discharge.
  • a third branch conduit 71 leads from the conduit 61 to a motor driven pump 73.
  • a check valve 75 is situated in the conduit 71 between the pump and that end of conduit 71 which communicates with the sea water outside of the capsule 27.
  • valve 64 As the capsule descends toward the probe 43 formed on the wellhead cellar 25, the valve 64 is opened so that sea water may continually circulate through main conduit 61 and branch conduit 62.
  • the valve '64 might be termed an equalizing valve since it provides for equal water pressure inside the lower compartment 31 of the capsule 27 and the ambient sea water located Outside the capsule 27.
  • an operator in the compartment 29 opens the valve 67 which communicates the sump or drain 69 at atmospheric pressure in the compartment 29 with the sea water located in the lower compartment 31 (via conduits '65 and 61). Due to the great pressure differential between the atmospheric pressure in compartment 29 and the much higher water pressure in the compartment 31 water will be rapidly displaced via conduits 61 and 65 from the compartment 31 to the sump or drain 69. This water displacement from compartment 31 into compartment 29 will continue until the pressure in compartment 31 equals the pressure in compartment 29 which is the pressure of one atmosphere or atmospheric pressure.
  • FIG. 3 the resilient seal member 55 is shown just before contact with the angled wall 47 of the cellar probe 43. Even after the seal 55 has contacted the angled wall 47 the metal surfaces 53 of the capsule and 45 of the cellar probe will not be in sealing contact. It is only after the valve 67 is opened and the capsule 27 moves rapidly downwardly onto the probe 43 that a possible fluidtight metal-to-metal seal is formed by engagement of the surface 45 with the surface 53. However, it should be noted that an adequate seal will be formed between seal 55 and the surface of angled wall 47 of probe 43. In addition to a possible metal-to-metal seal, the surfaces 45 and '53 cooperate to form a supporting arrangement for preventing the seal 55 from being crushed owing to the extreme weight of the capsule '27.
  • FIG. 4 The completed seal between the capsule 27 and the probe 43 on the wellhead cellar 25 is clearly shown in FIG. 4.
  • a metal-to-metal contact has been formed between the cellar probe surface 45 and the internal shoulder surface 53 of the capsule 27.
  • the resilient seal 55 has been compressed into fluidtight engagement throughout the entire length of the angled wall 47 of the cellar probe 43.
  • the possible metalto-metal seal between the surfaces 45 and 53 is backed up by the resilient seal member 55 thereby forming a double seal arrangement whenever the metal-to-metal seal exists.
  • the sealing arrangement of the present invention also utilizes the high pressure of the ambient sea water to effectuate an even tighter seal since the sea water acts agfainst the resilient member to compress it into tight engagement with the outer edge of the metalto-metal contact arrangement or seal.
  • a still further advantage of the metal-to-metal contact arrangement or seal formed by the surface 45 of the cellar probe 43 and the surface 53 of the capsule 27 resides in the fact that a solid metal support base is established between the capsule 27 and the wellhead cellar 25.
  • the supporting surface between the wellhead cellar and the capsule also forms a possible metalto-metal seal between the capsule and the wellhead cellar.
  • the area 81 of the resilient seal member 55 forms an O-ring type seal which backs up the outer edge or face of the metalto-metal contact arrangement or seal formed between the surfaces 53 and 45.
  • the resilient seal of the present invention combines the properties of both a simple gasket and an O-ring type gasket. As a pressure differential is created between the interior and exterior of the capsule 27 the sea pressure acting on the capsule and throughout the annular area denoted at X compresses the elastomeric seal 55 as a simple gasket. When metal-to-metal contact is made between the surfaces 45 and 53 the elastomeric seal 55 is captive having a residual pressure caused by the squeezing action and now functions as an interference seal.
  • the rubber seal pressure is a summation of sea pressure (or differential) and the induced residual pressure in the seal itself. It is the residual pressure that provides intimate contact between the rubber and the joint surfaces, thereby closing the possible leakage path.
  • the angle or slope of the wall 47 is aproximately 45 with respect to horizontal.
  • This sloping surface of the wall 47 allows falling or settling debris and marine life to slide away from the sealing surface and in addition acts as a force multiplier or wedge which helps prevent sea water blow-in.
  • the resilient seal 55 is preferably constructed of styrene-butadiene rubber because of its Waterresistant and rubber-like properties.
  • the cross-section and durometer of the resilient member are such as to preferably cause a compression of approximately in the seal to allow conformance with surface irregularities such as gouges, marine life protuberances or other surface roughness.
  • the motor driven pump 73 (see FIG. 2) is actuated.
  • the pump 73 pumps any remaining water out of the lower compartment 31 and an inner cavity 83 of the wellhead cellar 25 so that a hatch 85 which seals off an inner portion of the cellar 'will be exposed.
  • an operator in the upper compartment 29 opens the hatch 39 and descends into the lower compartment 31.
  • the latching dogs 89 serve as a mechanical tie-down and are employed to resist any forces which might tend to override the sealing forces and allow leakage or lift-off.
  • the operator closes the hatch 85 thereby sealing off the interior of the cellar.
  • the cable may now be released from the wellhead cellar 25 and reeled in on the winch 37.
  • the ram mechanisms 87 are then retracted so that the dogs 89 are unlatched from the annular flange 91.
  • the operator ascends into the upper compartment 29 and closes the hatch 39 thereby sealing off the upper compartment 29 from the lower compartment 31.
  • the valve 64 is now opened and since the ambient sea water is at a much greater pressure than the lower compartment 31 of the capsule, the lower compartment is quickly filled with sea water by way of the branch conduit 62 and the main conduit 61. After the sea water has reentered the lower compartment 31 a neutral condition exists between the capsule 27 and the wellhead cellar 25. Thus the capsule 27 is no longer being forced downwardly upon the cellar probe 43 since the water pressure inside the capsule 27 is equal to the water pressure outside the capsule. The operator inside the upper compartment 29 now signals the surface station 23 and personnel at the surface station begin pulling the capsule 27 upwardly to the water surface Where it is retrieved.
  • a seal for establishing fluidtight engagement between a submersible capsule and an underwater installation comprising, a flat annular surface and an angled wall surface on an end portion of said underwater installation that faces the submersible capsule, said capsule having a fiat annular surface for face-to-face mating engagement with the flat annular surface of said underwater installation, said capsule further having surfaces providing a recessed cavity with respect to the angeled wall of the underwater installation, and a resilient deformable sealing element disposed in said recessed cavity, said resilient sealing element having an angled surface facing the angled wall of the underwater installation, whereby upon engagement of said capsule with said underwater installation the resilient sealing member initially engages the angled wall to form an annular, relatively small width, fluidtight seal and whereby continued axial movement of the capsule onto the installation establishes a larger and tighter sealed area between said resilient member and the angled wall until said flat annular surfaces engaged in annular, metal-to-metal contact.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Geology (AREA)
  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geometry (AREA)
  • Gasket Seals (AREA)
  • Excavating Of Shafts Or Tunnels (AREA)
  • Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
US760807A 1968-09-19 1968-09-19 Sealing system for underwater installation Expired - Lifetime US3485056A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US76080768A 1968-09-19 1968-09-19

Publications (1)

Publication Number Publication Date
US3485056A true US3485056A (en) 1969-12-23

Family

ID=25060252

Family Applications (1)

Application Number Title Priority Date Filing Date
US760807A Expired - Lifetime US3485056A (en) 1968-09-19 1968-09-19 Sealing system for underwater installation

Country Status (6)

Country Link
US (1) US3485056A (xx)
BE (1) BE739077A (xx)
DE (1) DE1947260C3 (xx)
FR (1) FR2018462A1 (xx)
GB (1) GB1234540A (xx)
NL (1) NL6914295A (xx)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3739589A (en) * 1971-06-01 1973-06-19 Dixie Mfg Co Inc Mating shear seal device for connecting vessels and the like together
US3863458A (en) * 1972-12-21 1975-02-04 Komatsu Mfg Co Ltd Device for sinking and retrieving underwater heavy article
US3945213A (en) * 1974-05-08 1976-03-23 Subsea Equipment Associates Ltd. Subsea wellhead shielding and shock mitigating system
US4181453A (en) * 1977-08-24 1980-01-01 Sea Tank Co. Apparatus for positioning an off-shore weight structure on a previously positioned sea bed unit
US4521133A (en) * 1981-11-20 1985-06-04 The Yokohama Rubber Co., Ltd. Caisson for underwater structures
WO1989007070A1 (en) * 1988-02-06 1989-08-10 Mobil Oil Corporation Subsea support arrangement
US20150137460A1 (en) * 2012-07-17 2015-05-21 Toyota Jidosha Kabushiki Kaisha Sealing structure

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1803526A (en) * 1928-05-02 1931-05-05 Finn Anna May Submergible apparatus
US1834798A (en) * 1930-11-17 1931-12-01 Archie F Nair Rescue bell for rescue work on sunken submarines
US3265130A (en) * 1962-05-23 1966-08-09 Shell Oil Co Method and apparatus for drilling underwater wells
US3353364A (en) * 1962-04-26 1967-11-21 Gen Dynamics Corp Underwater well enclosing capsule and service chamber

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1803526A (en) * 1928-05-02 1931-05-05 Finn Anna May Submergible apparatus
US1834798A (en) * 1930-11-17 1931-12-01 Archie F Nair Rescue bell for rescue work on sunken submarines
US3353364A (en) * 1962-04-26 1967-11-21 Gen Dynamics Corp Underwater well enclosing capsule and service chamber
US3265130A (en) * 1962-05-23 1966-08-09 Shell Oil Co Method and apparatus for drilling underwater wells

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3739589A (en) * 1971-06-01 1973-06-19 Dixie Mfg Co Inc Mating shear seal device for connecting vessels and the like together
US3863458A (en) * 1972-12-21 1975-02-04 Komatsu Mfg Co Ltd Device for sinking and retrieving underwater heavy article
US3945213A (en) * 1974-05-08 1976-03-23 Subsea Equipment Associates Ltd. Subsea wellhead shielding and shock mitigating system
US4181453A (en) * 1977-08-24 1980-01-01 Sea Tank Co. Apparatus for positioning an off-shore weight structure on a previously positioned sea bed unit
US4521133A (en) * 1981-11-20 1985-06-04 The Yokohama Rubber Co., Ltd. Caisson for underwater structures
WO1989007070A1 (en) * 1988-02-06 1989-08-10 Mobil Oil Corporation Subsea support arrangement
US20150137460A1 (en) * 2012-07-17 2015-05-21 Toyota Jidosha Kabushiki Kaisha Sealing structure
US9541025B2 (en) * 2012-07-17 2017-01-10 Nok Corporation Sealing structure

Also Published As

Publication number Publication date
DE1947260B2 (de) 1977-08-11
FR2018462A1 (xx) 1970-05-29
DE1947260C3 (de) 1978-03-30
GB1234540A (xx) 1971-06-03
BE739077A (xx) 1970-03-19
NL6914295A (xx) 1970-03-23
DE1947260A1 (de) 1970-07-09

Similar Documents

Publication Publication Date Title
US3222088A (en) Wellhead connector with diagonally directed latches
US3795115A (en) Method and apparatus for joining subsea pipelines
US3482410A (en) Underwater flowline installation
US7845412B2 (en) Pressure control with compliant guide
US2988144A (en) Method and apparatus for drilling and completing underwater well bores
US3032125A (en) Offshore apparatus
US2854215A (en) Offshore oil well installation
US3333870A (en) Marine conductor coupling with double seal construction
US5085277A (en) Sub-sea well injection system
US3064735A (en) Wellhead assembly lock-down apparatus
US3179179A (en) Off-shore drilling apparatus
US3163223A (en) Wellhead connector
US20120111572A1 (en) Emergency control system for subsea blowout preventer
US6173781B1 (en) Slip joint intervention riser with pressure seals and method of using the same
US3350103A (en) Seal ring holding device
US3703207A (en) Subsea bunker construction
US3967462A (en) Method and apparatus for joining a subsea pipeline to an offshore platform riser
US3568767A (en) Telescoping wireline lubricator
US3638720A (en) Method and apparatus for producing oil from underwater wells
US3766978A (en) Remote controlled oil well pipe shear and shut-off apparatus
US4391330A (en) Apparatus and method for installing and energizing submergible pump in underwater well
US3656549A (en) Underwater completion system
US3485056A (en) Sealing system for underwater installation
US3527294A (en) Underwater exploration and completion system
US4284142A (en) Method and apparatus for remote installation and servicing of underwater well apparatus

Legal Events

Date Code Title Description
AS Assignment

Owner name: CANOCEAN RESOURCES LTD.

Free format text: CHANGE OF NAME;ASSIGNOR:LOCKHEED PETROLEUM SERVICES LTD.;REEL/FRAME:003991/0453

Effective date: 19820504