EP0109541B1 - Verbindungsvorrichtung für Rohrstrang - Google Patents

Verbindungsvorrichtung für Rohrstrang Download PDF

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Publication number
EP0109541B1
EP0109541B1 EP83110271A EP83110271A EP0109541B1 EP 0109541 B1 EP0109541 B1 EP 0109541B1 EP 83110271 A EP83110271 A EP 83110271A EP 83110271 A EP83110271 A EP 83110271A EP 0109541 B1 EP0109541 B1 EP 0109541B1
Authority
EP
European Patent Office
Prior art keywords
wellhead
sleeve
connector
housing
landing body
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
Application number
EP83110271A
Other languages
English (en)
French (fr)
Other versions
EP0109541A1 (de
Inventor
Michael Leonard Smith
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.)
FMC Corp
Original Assignee
FMC 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 FMC Corp filed Critical FMC Corp
Priority to AT83110271T priority Critical patent/ATE24224T1/de
Publication of EP0109541A1 publication Critical patent/EP0109541A1/de
Application granted granted Critical
Publication of EP0109541B1 publication Critical patent/EP0109541B1/de
Expired legal-status Critical Current

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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
    • 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
    • E21B33/038—Connectors used on well heads, e.g. for connecting blow-out preventer and riser

Definitions

  • This invention relates to pipe connectors, and more particularly to tie-back connectors for joining a riser pipe string to a casing hanger or other element in a subsea wellhead.
  • One of the prior types of pipe connectors for this purpose comprises a union nut style of threaded components that requires rotation of a relatively large ring or sleeve element to make up the connection. Not only is it difficutt.to properly align the riser with the wellhead so that cross-threading will not occur, it also is troublesome to rotate the ring or sleeve without the aid of special equipment and skilled personnel.
  • Another problem with union nut connectors is that their single shoulder is highly loaded when the connection is completed, and this stress results in an undesirably short fatigue life.
  • riser connector employs a turnbuckle-style assembly with right and left hand threads between a rotatable sleeve and the two pipe elements that are to be connected.
  • this connector type is . sound, in practice it requires undesirably high torque in order to produce the pre-load required for proper functioning.
  • British Patent 2 094 430 shows a torquing bushing which is threaded to a connector. After the connector has been put into place this bushing is unscrewed and dropped into the wellhead where it is then screwed into another thread.
  • EP-A--0 060 549 describes a pipe connector employing a differential thread system.
  • the present invention overcomes the foregoing problems and disadvantages by providing a riser tie-back connector with a differential thread system that facilitates landing, locking and sealing the riser to the wellhead without rotation of the riser, and that results in a releasable connection with substantially less stress concentration for a given pre-load than that produced by a union nut- type connector.
  • the differential thread system in the connector of the present invention is employed to first lock the connectorto the wellhead, and then to draw the connector seal surface axially into fluid-tight metal-to-metal contact with a sealing surface in the wellhead, both events being accomplished without the possibility of galling or otherwise damaging the seal surface such as might occur when they are joined by relative rotation.
  • the tie-back connector of the present invention includes an annular housing which, in use, is attached to the lower end of the riser, an annular landing body below the housing with a shoulder that seats the connector on a complementary stop shoulder in the wellhead, a rotatable sleeve interconnecting the housing and the landing body by means of a differential thread system, and a lock- down ring that is expanded by the sleeve to lock the connector to the wellhead.
  • Operational steps involved in using this tie-back connector to interconnect a riser with a wellhead include lowering the riser until the shoulder of the landing body comes to rest on the wellhead stop shoulder, rotating the connector sleeve to expand the lockdown ring into a mating recess in the wellhead, thus locking the connector to the wellhead, and rotating the connector sleeve further to move the housing axially into metal-to-metal sealed contact with the wellhead.
  • Rotation of the connector sleeve is accomplished by means of a torque tool attached to a drill pipe string that is lowered inside the riser, releasably connected to the sleeve, and then rotated with respect to the connector housing, landing body and lockdown ring.
  • the tie-back connector is associated with a guide assembly that is attached to the riser to seat against the wellhead and serve as a centralizer for the connector housing. Trash seals between the guide assembly and the wellhead protect the tie-back connector and other components of the installation from corrosion, a valuable additional feature should it become necessary to disconnect and remove the riser from the wellhead, for example if reinstallation of a subsea blowout preventer is required.
  • Figure 1 illustrates a riser tie-back connector assembly 8 interconnecting a subsea wellhead assembly 10 and a riser 12.
  • the wellhead assembly comprises a template 14, a guide assembly 16, guide posts 18 secured to the template 14 and anchoring guide cables 20 that extend to the surface drilling platform (not shown), a conductor housing 22 mounted on top of a conductor pipe 24, a wellhead 26 within and supported on the conductor housing 22, a first or outer casing hanger 28 supported in the wellhead 26 near the lower end thereof, and a second or inner casing hanger 30 also supported in the wellhead 26.
  • the second casing hanger 30 is locked into the wellhead 26 by a lockdown assembly 34, which assembly 34 also is utilized to transfer riser loads through the hanger 30 to the wellhead 26, and packoff assemblies 36, 38 establish a fluid-tight seal between the wellhead 26 and the first casing hanger 28, and between the wellhead 26 and the second casing hanger 30, respectively all in a conventional manner.
  • the riser tie-back connector assembly 8 which will be described in more detail with reference to Figure 2, includes.an annular housing 40 that is attached at its upper end by bolts 42 to the lower end of the riser 12.
  • the housing 40 is surrounded by a guide assembly 44, and the lower portion 40a of the housing 40 functions as an element of a lockdown assembly 46 for the tie-back connector, whereby the housing 40, the guide assembly 44, and the lockdown assembly 46 together constitute the tie-back connector assembly 8.
  • Mounted on this connector assembly 8 is a guide frame 48 to which are fixed a plurality of guide sleeves 50 (only two shown) for guiding the assembly 8 on its descent from the surface platform to the wellhead assembly 10.
  • the tie-back connector lock-down assembly 46 comprises the lower portion 40a of the housing 40, an annular landing body 52, a rotatable sleeve 54 and a lock- down ring 56.
  • the upper end portion of the sleeve 54 is connected to the housing 40 by threads 58
  • the landing body 52 is connected by threads 60 to the lower portion of the sleeve 54.
  • the threads 58, 60 are so related that they constitute a differential thread system, for example by differing in their pitch, whereby rotation of the sleeve 54 with respect to the housing 40 and landing body 52 in one direction tends to pull the housing and landing body towards each other, and rotation in the opposite direction tends to push the housing and landing body apart.
  • the landing body 52 includes an annular shoulder 52a that cooperates with a complementary shoulder 30a on the second or inner casing hanger 30, and the landing body is keyed to the hanger 30 at 62 to prevent rotation of the landing body with respect to the hanger.
  • the lockdown ring 56 which has a single axial split and is of resilient construction, is carried on the sleeve 54 surrounding its reduced outside diameter area 54a.
  • the upper end of the area 54a is formed by an annular frusto-conical shoulder 54b which functions to cam the ring 56 outwardly from a retracted condition in groove 54a (not shown) into an expanded condition ( Figure 2) as the sleeve 54 is threaded downwardly with respect to the landing body 52.
  • the lower end of the housing 40 is tapered to cooperate with an annular sholder 30b on the inside surface of the hanger 30 to establish a metal-to-metal seal at 66 between the housing and hanger.
  • Annular resilient seals 68 just above the metal-to-metal seal 66 provide a fluid-tight barrier between the housing 40 and hanger 30 prior to establishing the metal-to-metal seal 66.
  • the sleeve 54 similarly carries annular resilient seals 70 at its lower end to effect sealing engagement with the hanger 30, and an annular resilient seal 72 at the upper end of the sleeve 54 provides the requisite trash seal between the sleeve and the housing 40.
  • the tie-back connector assembly 8 and the riser-12 to which it is attached are lowered to the subsea wellhead assembly 10.
  • the guide assembly 44 contacts and seats on the wellhead 26, thus serving as a centralizer for the housing 40.
  • a downward force is then applied to the housing 40 through the riser 12, pushing the housing and the tie-back connector lockdown assembly 46 further into the wellhead 26 until the landing body shoulder 52a lands and seats on the casing hanger shoulder 30a ( Figure 2).
  • a torquing tool (not shown) is then lowered through the riser 12 by means of a drill pipe string (not shown).
  • a drill pipe string (not shown).
  • elements on the tool expand into these grooves and releasably lock the tool to the sleeve.
  • the drill string is then rotated, thereby rotating the running tool and the sleeve 54.
  • the sleeve 54 rotates it moves downwardly within the landing body 52, thereby expanding the lockdown ring 56 into the mating grooves in the casing hanger 30 and securing the body 52 against upward movement.
  • the differential threads 58, 60 cause the connector housing 40 to move downward until its lower end comes to rest on the hanger shoulder 30b, thereby establishing a metal-to-metal seal at 66 between the sleeve and the hanger. Accordingly, at this final position three seals exist between the connector assembly and the hanger 30, i.e. the two resilient seals 68 and the metal-to-metal seal 66, thereby assuring the maintenance of pressure integrity between the riser annulus and the exterior of the wellhead installation.

Landscapes

  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Physics & Mathematics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Non-Disconnectible Joints And Screw-Threaded Joints (AREA)
  • Coupling Device And Connection With Printed Circuit (AREA)
  • Connector Housings Or Holding Contact Members (AREA)
  • Ladders (AREA)
  • Quick-Acting Or Multi-Walled Pipe Joints (AREA)

Claims (7)

  1. . 1. Rohrstrang-Verbindungseinrichtung (8) zum Verbinden eines Steigrohres (12) mit einem Unterwasser-Förderkopf (10) ohne Rotation dieses Steigrohres, wobei diese Verbindungseinrichtung (8) enthält:
    a) ein Gehäuse (40), welches mit diesem Steigrohr verbunden ist,
    b) eine Hülse zum Verbinden des Gehäuses und des Förderkopfes, dadurch gekennzeichnet, daß:
    c) ein Anschlagkörper (52) über ein erstes Gewinde (60) mit dieser Hülse (54) verbunden ist, wobei dieser Anschlagkörper Einrichtungen (52a) aufweist, um auf einer Schulter (30a) in einem Förderkopf-Element (30) aufzusitzen,
    d) in diese Hülse (54) über ein zweites Gewinde (58) mit diesem Gehäuse (40) verbunden ist,
    e) dieses erste und dieses zweite Gewinde als unterschiedliche Gewinde geformt sind,
    f) Befestigungseinrichtungen (62) vorgesehen sind, um diesen Anschlagkörper (52) mit diesem Förderkopf-Element (30) zu verbinden und um die Rotation dieses Anschlagkörpers in bezug auf dieses Förderkopf-Element (30) zu verhindern,
    g) ein geteilter Befestigungsring (56) in bezug zu dieser Hülse (54) in einer solchen Weise angeordnet ist, daß nach der Rotation dieser Hülse (54) relativ zu diesem Gehäuse (40) und diesem Anschlagkörper (52), dieser geteilte Ring (56) in eine Nut in diesem Förderkopf-Element (30) ausgedehnt wird, wobei die Verbindungseinrichtung mit diesem Förderkopf verbunden wird und eine Metall-zu-Metall-Dichtung (66) zwischen einer unteren Position (40a) dieses Gehäuses (40) und einer weiteren Schulter (30b) dieses Förderkopf-Elementes gebildet wird,
    h) Einrichtungen (80) zur Rotation diese Hülse (54) relativ zu diesem Gehäuse (40) vorgesehen sind.
  2. 2. Verbindungseinrichtung gemäß Anspruch 1, dadurch gekennzeichnet, daß:
    diese Rotation dieser Hülse (54) zuerst diesen Anschlagblock (52) mit diesem Förderkopf-Element (30) verbindet, indem dieser geteilte Ring (56) in diese Nut in dieses Förderkopf-Element (30) gesetzt wird und dann die Metall-zu-Metall-Dichtung (66) zwischen diesem Gehäuse und diesem Förderkopf-Element bewirkt, indem dieses Gehäuse zu diesem Anschlagkörper gezogen wird.
  3. 3. Verbindungseinrichtung gemäß Anspruch 1 oder Anspruch 2, dadurch gekennzeichnet, daß: eine Nut (54a) in dieser Hülse (54) vorgesehen ist, um den geteilten Ring im ungedehnten Zustand zu tragen und daß dieser geteilte Ring aus dieser Nut bewegt wird, durch ein Anstossen an diesen Anschlagkörper (52) und durch diese Hülse in einen verbindenden Eingriff mit dieser Nut in dieses Förderkopf-Element durch fortgesetzte Rotation und Einschrauben dieser Hülse in diesen Anschlagkörper gedehnt wird.
  4. 4. Verbindungseinrichtung gemäß mindestens einem der vorgehenden Ansprüche, dadurch gekennzeichnet, daß:
    eine elastische Dichtung (68) in diesem Gehäuse vorgesehen ist, und zwar vorzugsweise an dessen unteren Ende, um eine flüssigkeits- , dichte Dichtung zwischen diesem Förderkopf-Element (30) und diesem Gehäuse (40) zu bewirken.
  5. 5. Verbindungseinrichtung gemäß mindestens einem der vorgehenden Ansprüche, dadurch gekennzeichnet, daß eine elastische Dichtung (70) an dem unteren Ende der Hülse (54) vorgesehen ist, zur flüssigkeitsdichten Abdichtung zwischen dem unteren Ende dieser Hülse (54) und diesem Förderkopf-Element (30).
  6. 6. Verbindungseinrichtung gemäß mindestens einem der vorgehenden Ansprüche, dadurch gekennzeichnet, daß eine elastische Dichtung (72) an dem unteren Endteil dieser Hülse (54) zur Abdichtung zwischen dieser Hülse (54) und dem Gehäuse (40) vorgesehen ist.
  7. 7. Verfahren zum Verbinden eines Steigrohres mit einem Unterwasser-Förderkopf ohne Rotation dieses Steigrohrs, wobei eine Vorrichtung gemäß mindestens einem der vorgehenden Ansprüche verwendet wird und wobei dieses Verfahren folgende Schritte aufweist:
    a) das Befestigen des Rohrverbinders (8) mit einem Steigrohr (12);
    b) das Einführen des unteren Teils dieser Verbindungseinrichtung (8) in den Förderkopf und das Aufsetzen des Anschlagkörpers (52) auf der ersten Schulter (30a);
    c) das Rotieren der Hülse (54) und Ziehen des Gehäuses (40) und des Anschlagkörpers (52) zueinander und das Ausdehnen dieses geteilten Rings (56) und das Befestigen dieser Verbindungseinrichtung (8) an diesen Förderkopf (10); und
    d) das fortgesetzte Rotieren dieser Hülse (54) und das Aufbauen einer Metall-zu-Metall-Dichtung (66) zwischen diesem Gehäuse (40) und dieser zweiten Schulter (30b) auf diesem Förderkopf-Element (30).
EP83110271A 1982-10-14 1983-10-14 Verbindungsvorrichtung für Rohrstrang Expired EP0109541B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83110271T ATE24224T1 (de) 1982-10-14 1983-10-14 Verbindungsvorrichtung fuer rohrstrang.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
PCT/US1982/001474 WO1984001610A1 (en) 1982-10-14 1982-10-14 Pipe string tie-back connector
WOPCT/US82/01474 1982-10-14

Publications (2)

Publication Number Publication Date
EP0109541A1 EP0109541A1 (de) 1984-05-30
EP0109541B1 true EP0109541B1 (de) 1986-12-10

Family

ID=22168293

Family Applications (2)

Application Number Title Priority Date Filing Date
EP82903541A Withdrawn EP0122259A1 (de) 1982-10-14 1982-10-14 Verbindungsvorrichtung für rohrstrang
EP83110271A Expired EP0109541B1 (de) 1982-10-14 1983-10-14 Verbindungsvorrichtung für Rohrstrang

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP82903541A Withdrawn EP0122259A1 (de) 1982-10-14 1982-10-14 Verbindungsvorrichtung für rohrstrang

Country Status (9)

Country Link
EP (2) EP0122259A1 (de)
JP (1) JPS59501676A (de)
AT (1) ATE24224T1 (de)
AU (1) AU555841B2 (de)
BR (1) BR8305690A (de)
CA (1) CA1205741A (de)
DE (1) DE3368306D1 (de)
NO (1) NO842363L (de)
WO (1) WO1984001610A1 (de)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BR8503800A (pt) * 1985-08-12 1987-03-17 Cbv Ind Mecanica Equipamento para instalacao de modulos em bases submersas fixas,especialmente para pocos de petroleo submarinos
GB2193773A (en) * 1986-08-08 1988-02-17 Howden James & Co Ltd Pipeline safety joint
US4962952A (en) * 1989-03-29 1990-10-16 Vetco Gray Inc. Pressure tube with deflecting section
US4976458A (en) * 1989-10-16 1990-12-11 Vetco Gray Inc. Internal tieback connector
GB9123928D0 (en) * 1991-11-11 1992-01-02 Alpha Thames Eng Two-part connector for fluid carrying container
US5924491A (en) * 1997-07-03 1999-07-20 Baker Hughes Incorporated Thru-tubing anchor seal assembly and/or packer release devices
US7467663B2 (en) * 2004-09-07 2008-12-23 Dril-Quip, Inc. High pressure wellhead assembly interface
US7861789B2 (en) * 2005-02-09 2011-01-04 Vetco Gray Inc. Metal-to-metal seal for bridging hanger or tieback connection
US9303480B2 (en) * 2013-12-20 2016-04-05 Dril-Quip, Inc. Inner drilling riser tie-back connector for subsea wellheads

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3521909A (en) * 1965-05-19 1970-07-28 Richfield Oil Corp Remote underwater wellhead connector
US3489213A (en) * 1968-04-18 1970-01-13 Fmc Corp Underwater well completion system
US4046405A (en) * 1972-05-15 1977-09-06 Mcevoy Oilfield Equipment Co. Run-in and tie back apparatus
US3809158A (en) * 1972-07-27 1974-05-07 Rockwell International Corp Well completion apparatus and method
US3986729A (en) * 1975-08-11 1976-10-19 Cameron Iron Works, Inc. Connecting apparatus
US4085951A (en) * 1976-10-28 1978-04-25 Wonder Products Company Hydril-type connector
US4408784A (en) * 1981-03-06 1983-10-11 Vetco, Inc. Production casing tieback connector assembly
CA1173076A (en) * 1981-03-16 1984-08-21 Michael R. Williams Thread-type pipe connector

Also Published As

Publication number Publication date
NO842363L (no) 1984-06-13
EP0109541A1 (de) 1984-05-30
AU555841B2 (en) 1986-10-09
ATE24224T1 (de) 1986-12-15
DE3368306D1 (en) 1987-01-22
BR8305690A (pt) 1984-07-10
AU9126282A (en) 1984-05-04
WO1984001610A1 (en) 1984-04-26
EP0122259A1 (de) 1984-10-24
JPS59501676A (ja) 1984-10-04
CA1205741A (en) 1986-06-10

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