Equally tensioned coupling apparatus

• US 4,222,590 A
• Filed: 02/02/1978
• Issued: 09/16/1980
• Est. Priority Date: 02/02/1978
• Status: Expired due to Term

• Current Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Original Assignee: Regan Offshore International Incorporated
• Inventors: Regan, John
• Primary Examiner(s): Arola, Dave W.
• Application Number:
  US05/874,622
• Time in Patent Office: 957 Days
• Field of Search: 285/18, 285/14, 285/24, 285/321, 285/27, 285/39, 285/96, 285/DIG. 21, 285/363, 285/405, 403/15, 403/34, 29/252, 29/452, 254/29 A, 85/1 T, 85/32 T
• US Class Current: 285/14
• CPC Class Codes: E21B 17/085 Riser connections connectors for wellhead E21B33/038
• CPC Class Codes: F16L 23/036 characterised by the tensioning members, e.g. specially adapted bolts or C-clamps
• CPC Class Codes: Y10S 285/92 Remotely controlled
• CPC Class Codes: Y10T 403/1633 Utilizing fluid pressure

Abstract

The present invention discloses method and apparatus for connecting together two members having mating surfaces by means of a plurality of fasteners such that equal compression forces are exerted on the members along force lines normal to a common plane. To accomplish the foregoing objectives, a plurality of pins are carried by one member and pass through bores in the opposite member. The pins are longitudinally extended simultaneously with a common internal extending force and stops are affixed to the ends extending through the second member snugly against the surface thereof. Upon release of the common extending force, all the pins attempt to restore to their original positions with equal restorative forces being equal and opposite to the common extending force applied thereto.

Claims

1. Coupling apparatus for releasably coupling a pair of conduits comprising:

(a) a first connector member adapted to connect to one of the conduits on one end and having a flange on the other end, said flange having a plurality of radially spaced holes therethrough;

(b) a second connector member adapted to connect to the other end of the conduits on one end and having a flange on the other end, said flange of said second connector member being adapted to mate with said flange of said first connector member when the two conduits are disposed in end-to-end relationship;

(c) a plurality of connector pins carried by said flange of said second connector member on one end and means connecting said one end to said flange of said second connector member, said pins having threads on the opposite end, said pins being disposed to pass through said holes with said threads projecting therefrom, said pins further being hollow cylinders filled with a first fluid and having sidewalls sufficiently thick to resist lateral deformation and only extend the pin when said first fluid is pressurized;

(d) a plurality of nuts adapted for threaded engagement with said threaded ends; and

,

(e) means for internally exerting an identical longitudinal extending force on said pins whereby said nuts can be threaded onto said threads of each of said pins to snug engagement with said flange of said first connector member with said pins under said longitudinal extending force whereby with said longitudinal extending force removed therefrom all said pins are under identical tension, said extending force exerting means comprising a passageway filled with a second fluid disposed in pressure transmitting communication with said first fluid in each of said plurality of pins at respective interfaces thereof, said passageway being adapted for connection to a source of hydraulic pressure whereby upon connection of said passageway to a source of hydraulic pressure equal forces are transmitted through said second fluid to said first fluid and all said pins simultaneously so that said pins are subjected to an equal internal expanding force only by said first fluid under pressure.

2. The coupling apparatus claimed in claim 1 and additionally comprising:

sealing means disposed at said respective interfaces between said first fluid and said second fluid.

3. The coupling apparatus claimed in claim 1 wherein:

(a) said passageway is an annular passageway disposed in said flange of said second connector member;

(b) said pins include a pressure deformable portion communicating with said first fluid; and

,

(c) said flange of said second connector member includes a plurality of connecting passageways disposed between said annular passageway and said pressure deformable portion of respective ones of said pins.

4. The coupling apparatus claimed in claim 3 wherein:

(a) said pins are releasably carried by said flange of said second connector member by said means connecting said pins to said flange of said second connector member; and

,

(b) said apparatus additionally comprises a plurality of deformable seals disposed in respective ones of said connecting passageways between said second fluid and said pressure deformable portion of said pins and in contact with said latter named portion whereby said pins can be removed and replaced without loss of said second fluid.

5. In apparatus for connecting together two members having mating surfaces by means of a plurality of fasteners, the improvement for causing equal compression forces to be exerted on the members along force lines normal to a common plane by all the fasteners comprising:

(a) one of the members including an integral manifold adapted for connection to a source of fluid under pressure, the member also including a plurality of bores extending into the member from the side thereof having the mating surface along lines normal to the common plane to connect into said integral manifold, and further including means for releasably and sealably engaging pins inserted into said bores;

(b) the other of the members including a plurality of bores concentrically aligned with said bores in the one member;

(c) a plurality of hollow, cylindrical, fluid-filled pins inserted into respective ones of said bores of the one member, each of said pins having a deformable diaphragm on the end thereof inserted into said bores of the one member and means for engaging said engaging means of the one member whereby said pins are held in said bores of the one member with said deformable diaphragms in sealed communication with said integral manifold, said pins each also being non-deformable on the end not inserted into said bores of the one member and having means adjacent said last named end for releasably and adjustably engaging a stop, the portion of said pins not inserted into the bores of the one member being adapted to pass through said bores in the other member, said pins having sidewalls between said two ends of a thickness so as to resist lateral deformation while allowing maximum longitudinal extensibility in response to pressurization of said internal fluid; and

,

(d) a plurality of stops adapted for mounting adjacent said non-deformable end of respective ones of said pins, said stops being unable to pass through said bores in the other member and including means for engaging said stop engaging means on said pins whereby said stops can be releasably positioned longitudinally on said pins close adjacent the other member opposite the mating surface thereof with said pins longitudinally extended through the application of fluid pressure through said internal manifold and said deformable diaphragm to said internal fluid so that said pins will subject the two members to identical compression forces through said stops by the restorative force of said pins when said fluid pressure is released from said manifold.

6. The improved connecting apparatus claimed in claim 5 and additionally comprising:

(a) a plurality of deformable sealing members disposed in respective ones of said bores of the one member between said deformable diaphragm and said internal manifold and in contact with said deformable diaphragm whereby if one of said pins is removed the associated one of said bores remains sealed with respect to said internal manifold; and

,

(b) a fluid filling said integral manifold in contact with said deformable sealing members whereby when said integral manifold is connected to a source of fluid under pressure the pressure will be transmitted from the last named fluid into said fluid filling said integral manifold to deform said sealing members against said deformable diaphragms to thereby deform said diaphragms against said fluid filling said pins to create a pressure within said pins to cause the longitudinal extension thereof and whereby said pins can be removed from said bores in the one member without loss of said fluid filling said integral manifold.

7. The improved connecting apparatus claimed in claim 5 wherein:

(a) the ends of said pins having said deformable diaphragms therein are threaded;

(b) said bores of the one member are threaded; and

,

(c) said pin engaging means comprises internally and externally threaded sleeves threaded into said threaded bores of the one member, said pins being threaded therein, said sleeves being of reduced wall thickness in the area thereof disposed adjacent the bottom of said last named bores whereby an internal clearance area is created circumferentially between said pins and said sleeves and an external clearance area is created circumferentially between said sleeves and said bores, said reduced thickness area having a passageway therein between said internal and external areas, the one member having a passageway communicating between the atmosphere and said external clearance area whereby a relief path is created for the escape of air and fluid trapped within said bores of the one member.

8. The improved connecting apparatus claimed in claim 5 wherein:

(a) said other member has a biased gripping means in sliding engagement with said pins when said pins are disposed through said bores of said other member;

(b) said pins have means for releasably engaging said gripping means disposed to hold said pins in a position disengaged from said bores in the one member and preventing said pins from falling out of said bores in the other member.

9. The improved connecting apparatus claimed in claim 8 wherein:

(a) said bores of the other member each have a retaining groove concentrically disposed therein and said biased gripping means comprises a plurality of snap rings disposed within respective ones of said retaining grooves; and

,

(b) said means for engaging said gripping means comprise at least a pair of ridges on the external sidewalls of each of said pins.

10. The improved connecting apparatus claimed in claim 9 wherein:

at least one of said ridges is disposed circumferentially about each of said pins at a point substatially at the longitudinal midpoint of said longitudinally extensible sidewalls and is in sliding contact with the sidewalls of said bore of the other member whereby lateral deformation of the sidewalls of said pins when said pins are internally pressurized is prevented.