US3163223A

US3163223A - Wellhead connector

Info

Publication number: US3163223A
Application number: US127054A
Authority: US
Inventors: Richard J Baner; John A Haeber; Lloyd G Otteman; Raymond F Perner
Original assignee: Shell Oil Co
Current assignee: Shell USA Inc
Priority date: 1961-07-26
Filing date: 1961-07-26
Publication date: 1964-12-29
Anticipated expiration: 1981-12-29
Also published as: GB956640A

Description

Dec. 2 9, 1964 R. J. BAUER ETAL WELLHEAD CONNECTOR Filed July 26, 1961 3 Sheets-Sheet 1 INVENTORS= R. J. BAUER .1. A. HAEBER L.G. OTTEMAN FIG-l R.F. PERNER THEIR AGENT Dec. 29, 1964 R. J. BAUER ETAL 3,163,223

WELLHEAD CONNECTOR Filed July 26, 1961 3 Sheets-Sheet 2 FIG. 3

INVENTORS:

R. J. BAUER J.A. HAEBER L.G. OTTEMAN R.F. PERNER BY; H .16 EIR AGENT Dec. 29, 1964 R. J. BAUER ETAL 3,153,223

WELLHEAD CONNECTOR Filed July 26, 1961 3 Sheets-Sheet 3 THEIR AGENT United rates Patented Dec. 29, 1964 3,163,223 WELLHEAD CONNECTOR Richard J. Bauer, Westport, Conn, John A. Haeher and Lloyd G. Utteman, Houston, Ten, and Raymond F. Perner, Metairie, Ln, assignors to Shell Gil Company,

New York, N.Y., a corporation of Delaware Filed July 26, E63, Ser. No. 127,954

4 Claims. Zl. 166-665) This invention relates to apparatus for use on offshore wells and pertains more particularly to a wellhead apparatus adapted to be securely locked on a well casinghead positioned underwater. The present invention is especially concerned with apparatus for connecting a wellhead component, such for example as a blowout preventer, to a vertically-extending wellhead component in a securely locked and fluidtight manner so that the wellhead component could not he accidentally separated from the vertically-extending well member.

*In an attempt to locate new oil fields, an increasing amount of well drilling has been conducted at offshore locations, such for example, as off the coast of Louisiana, Texas and California. As a general rule, the strings of casing in a well together with the tubing string or strings extend .to a point well above the surface of the water where they are closed in the conventional manner that is used on land wells, with a conventional wellhead assembly eing attached to the top of the casing. Attempts have been recently made to provide methods and apparatus for drilling and completing a well wherein both the well casinghead and subsequently .the wellhead assembly and casinghead closure device are located underwater at a depth sufiicient to allow ships to pass over them. Preferably, the casinghead and wellhead closure assemblies are located close to the ocean floor. In order to install equipment of this type underwater in depths greater than the shallow depth at'which a diver can easily operate, it has been necessary to design entirely new equipment for this purpose. Thus, when drilling and completing an oil or gas well at an offshore location in a manner described in copending patent application, Serial No. 830,538, filed July 30, 1959, and entitled Underwater Well Completion Method, the well casinghead may have attached thereto various pieces of equipment by means of the apparatus of the present invention.

It is therefore a primary object of the present invention to provide apparatus for connecting a wellhead component to an underwater wellhead assembly while operating the apparatus from a remote location.

It is another object of the present invention to provide a wellhead such as a blowout preventer with a connector device so that the blowout preventer may be lowered on guide lines and seated on an underwater well casinghead and securely locked thereto in a fluidtight manner with the sea-ling and locking operations being carried out from a remote location.

-A further object of the present invention is to provide,

a remotely operable connector apparatus adapted to lock on to an underwater wellhead and pack oh the annulus between the connector device and the wellhead.

Another object of the present invention is to provide a remotely-controlled hydraulically-operated connector device and sealing apparatus for holding a wellhead component on a wellhead against pressures which might be encountered therein at any time, even in the event that the hydraulic pressure lines to said apparatus should break, or otherwise become inoperative. V

A still further object of the present invention is to provide a wellhead connector device and sealing apparatus which may readily be unlocked from an underwater .wellhead and withdrawn to an operational base at the surface, such for example to a drilling barge or platform.

' in FIGURE 1 as comprising a base member 21 which is Another object of the present invention is to provide a wellhead connector device adapted to seat on an underwater wellhead and be connected to the inside thereof,-

rather than the outside thereof, so that the seating and latching surfaces of a well casinghead are isolated in a manner such that they are protected from corrosion, from sea water and from marine growth that would prevent a tool being telescoped over a well casinghead and latched thereon. 7

These and other objects of this invention will be understood from the following description taken with reference to the drawing, wherein:

FIGURE l is a diagrammatic view illustrating a floatable drilling barge positioned on the surface of the ocean from which a blowout preventer together with the connector device of the present invention is being lowered to the top of a well casinghead positioned on the ocean floor; and

FEGURES 2, 3 and 4 are views taken in longitudinal cross-section of several forms of a wellhead connector illustrated as being positioned in a vertically-extending well member in its sealed and latched position.

Referring to FIGURE 1 of the drawing, a drilling barge 1-1, of any suitable floatable type is illustrated as floating on the surface of the water 12 and fixedly positioned over a preselected drilling location by being anchored to the ocean fioor 13 by suitable anchors (not shown); Equipment of this type may be used when carrying on Well drilling operations in water depths varying from about to 1500 feet or more. The drilling barge is equipped with a suitable derrick 16 and a rotary table 17 as well as other auxiliary equipment needed during the drilling of a well.- The derrick '16 is positioned over a drilling slot or well 18 which extends vertically through the barge in a conventional manner. When using the equipment of the present invention the slot '18 and the barge l l maybe either centrally located or extend in from one edge. However, drilling operations may be carried out over the side of the barge without the use: of 'a slot. Additionally, it is to be understood that the equipment of the present invention may also be used while drilling a well from any suitable operational base positioned above the surface of a body of water, such for example as from a drilling barge having feet extending to the ocean floor, or :from a platform permanently positioned on the ocean floor.

A typical underwater wellhead structure is illustrated positioned on the ocean floor 113 and is fixedly secured to a conductor pipe or large-diameter well casing 22 which extends down into a well, which has been previously drilled, and is cemented therein. Thus, the base structure Ed is rigidly secured to the ocean floor in order to support two or more vertically-extending guide columns 23 and 24 adapted to receive and guide therein arms 25 and 26 which are arranged to slide along vertically-extending guide cables 27 and 28. The lower ends of the guide cables 27 and 23 are anchored to the base structure 21 within the guide columns v2?; and 24 while extending upwardly through the water to the drilling barge 11 where they are preferably secured to constant tension hoists 31 and 32.

Centrally positioned above the base plate 21 and fixedly secured thereto, or to the conductor pipe 22, is a well more grooves, and extend around the inner wall of the casinghead. The wellhead is also shown as being provided with a cement circulation or kill line 36 which is connected preferably by means of a quick-disconnect coupling 37'to a flow-control valve 38.

FIGURE 1 the wellhead connector'41 is shown as it is being lowered into the top of the casinghead 33. The combined blowout preventer and wellhead connectorl) and 41, respectively, are run into positionon the top'of the well by being lowered through the water from the barge 11 by means of a pipe string 42, commonly known as a running string, the blowout preventer 40 being connected to the lower end of the running string 42 by means of a suitable coupling or connector 43 which may take the form of the wellhead connector 41. The valve 38, connector 41, blowout preventer 40 and connector .3 are all hydraulically operated and are provided with

hydraulic flowlines

44 and 45, 46 and 47, 48 and 4?, and 50 and 51, respectively. 'These fiowlines, 44 through 51, extend up- .wardly from the wellhead equipment to the barge 11 where they areconnected to a suitable source of pressure fluid.

Referring to FIGURE 2 of the drawing, the wellhead connector 41 is illustrated as being seated'in the casinghead 33. A seal 54 may be provided at the top of the casinghead 33 to seal the space between the top, of the casinghead 33 and the flange 55by which the wellhead conventer4 (FIGURE 1). the sea water out of the apparatus.

The sealing element 54keeps Thebody of the wellhead connector, preferably near the lower end thereof, is provided with a shoulder .seating'surface d adapted to itself may seat directly on the top of the casinghead 33'."

An annular seal 58 is preferably carried on the outersurface of the wellhead'connector 41 and is expandable .nector 41 is secured to the bottom 'of the blowout pre-,

throughconduits

47 and 62 to force the piston upwardly to the top of the chamber 61. The wellhead connector is provided with a vertical bore 72 through which drilling'oper-ations may be carried out, or equipment run into the well.

Another form of the present wellhead connector is illustrated in FIGURE 3. This arrangement ditfers from that described with regard to FIGURE 2 in that the dogs 64- are positioned above the annular seal 58, and the piston 59 has a single camming face 66 which is adapted to actuate sequentially both the locking dogs 64v and the annular seal 58.

A third modification of the wellhead connector of the present invention is illustrated in FIGURE 4. In this embodiment, an annular seal 75 is provided which is expanded against the inner wall of the casinghead 33 when the lower end of the wellhead connector 41a, which is slidably mounted on a reduced diameter portion 41b of the wellhead connector 41, is forced upwardly. A suitable stop member 76 or anchoring ring 'is provided on the outer surface of the lower end portion 41b of the wellhead connector 41 for preventing the slidable portion 41a from dropping off as the apparatus is inserted into a casinghead. If desired,

additional seals

77 and 78 may be provided in thevertical wallin the seating shoulder of slidable element 41a. 7

While the blowout preventer 46 (FIGURE 1) of the present invention'has been described with regard to having a wellhead connector 41 secured to the lower end thereof for locking the blowout preventer into the top of a well 7 casinghead, it is to be understood that the blowout p're: venter could have a similar wellhead connector 41a (FIG- URE 5) extendingupwardly therefrom to receive and against. the inner surface of the casinghead 33 by means I of a tubular-shaped piston element 5 9; The piston 59 is slidably mounted within an annular chamber 61. A 'pair of conduits 62 and '63 extend through the .W8llh63d C0I1 nectorl and are in communication with the upper and lower ends of the. chamber 61.

The wellhead connector 41 is also provided with a series of outwardly-extendible locking dogs 64 which are adapted to be forced outwardly into one or more annular grooves 65, cut in the inner face of the casinghead 33, upon downwardly movement of the piston 59. The piston element 59 is provided with a downwardly and inwardly sloping face 66 which forcesthe dogs 64 into their locking 5 position. The outer upper edge of the locking dogs 64 are preferably bevelled, as at 67, so that the dogs 64 are readily retracted into the wellhead connector 41 upon an upward pull of the wellhead connector 41 with respect to the casinghead 33, after the piston element 59 has been raised'to its uppermost position. .Although the carnming surface 66 of the piston 59 can .be utilized to actuate sequentially first the annular seal 58 and then the locking 7 dogs 64, the piston 59 is preferably provided with a second downwardly and inwardly sloping'face 68 spaced above face'ti a'suitable distance so that the seal'58 and the lock- 1 ing dogs'fi lare simultaneously actuated. By using two camming surfaces 6 6 and 68, the stroke of the piston.59 can be materially shortened. Y

j In order tooperate the locking dogs 64 of the present apparatus, it is necessary that a pressure fluid be supplied 1 from the barge 11 (FIGURE 1) down through conduit 46 whichis in communication with conduit 63 (FIGURE'Z) of thewellhead connector 41. The pressure fluid'forces piston 5% downwardly, which in turn actuates the seal 58 and the lockingdogs 64. The locking dogs 64 are premitted to extend outwardly a distance equal'to the width 1 of a vertical slot 70 in each dog, minus thediam ete'r of a retaining pin 71; which prevents the dog64 from falling oittjof the apparatus. To unlock the dogs and unsealthe wellhead connector, pressure fluid would be supplied lock thereon the lower end of a large diameter pipestring or marine conductor 89 which would extend from the wellhead to a point above the surface of the water, as to abarge. Use of a second wellhead connector at the top of :a blowout preventer which was already positioned in a well, would greatly simplify running additional pipe member, a blowout preventer lock-down apparatus se' cured to at least one end of said blowout preventer coaxial therewith, said lock-down apparatus comprising a cylindrical body member having an axial bore therethrough and being of a size-to fitinto the open upper. end of, said vertically projecting tubular well member, outwardly extending shoulder means formed on the outside of said body member, said shoulder means having a diameter greater than that of at least a portion of the bore of said tubular well member in which itfits, locking means movablytcarried by said body member and being bodily movable outwardly thereofiso that a: portion of said lock-- ing means projects beyond the surface of saidbody meme berrtoward; and into contact with seating. groove. means in the inner surface of said well member, annular seal means carried outwardly on said body member adapted" to form a fluidtight seal with asurrounding well member,

and actuating means carried by .said body member for operatively'engaging said locking means, said actuating means being movable'with respect to saidbody member in response to fluid pressure application thereto to move,

said locking means outwardly of saidbody member into 'locklng'position with a surrounding well member thereby preventing separation of said body member and said well 7 member; said apparatus containing pressure fluid port 1 to the bottom of the piston 59 means in fluid communication on one end with the actuating means in said body member with the other end extending through the wall of said body member and adapted to communicate with a source of pressure fluid.

2. An apparatus for facilitating underwater wellhead operations which in assembly comprises a vertically projecting tubular well member, a blowout preventer adapted to be mounted on the upper end'of said tubular well member, a blowout preventer lock-down apparatus secured to at least one end of said blowout preventer coaxial therewith, said lock-down apparatus comprising a cylindrical two-piece body member having upper and lower portions with an axial bore therethroughand being of a size to fit into the open upper end of said vertically projecting tubular well member, the upper portion of said body member having a downwardly extending tubular element, the .lower portion of said body member being mounted on said downwardly extending tubular element for limited axial slidable movement relative to said upper portion, an annular resilient seal carriedby said body member between the upper and lower portions thereof, said seal being of a diameter to project beyond the outer surface of said body member when compressed between said upper and lower portions thereof, outwardly extending shoulder means formed on the outside of the lower portion of said body member, said shoulder means having a diameter greater than that of at least a portion of the bore of said tubular well member in which it fits, locking means carried by said body member and being bodily movable outwardly thereof so that a portion of said locking means projects beyond the surface of said body member toward and into. contact with seating groove means in inner surface of said well member, and actuating means carried by said body member for operatively engaging said locking means, said actuating means being movable with respect to said body member in response to fluid pressure application thereto to move said locking means outwardly of said body member into locking position with a surrounding well member thereby preventing separation of said body member and said well member, said apparatus containing pressure fluid port means'in fluid communication on one end with the actuating means in said body member with the otherend extending through the wall of said body member and adapted to communicate with a source of pressure fluid.

3. An apparatus for facilitating underwater wellhead operations which in assembly comprises a verticallyprojecting tubular well fitting, a blowout preventer adapted to be mounted on the upper end of said tubular well fitting, a blowout preventer lockdown apparatus secured to each of the upper and lower ends of said blowout preventer coaxial with the bore therethrough, each said lockdown apparatus comprising a cylindrical body member having an axial bore therethrough and being of a size to fit into the open end of said vertically-arranged tubular well fitting, outwardly extending shoulder means formed on the outside of said body member, said shoulder means having a diameter greater than that of at least a portion of the bore of said tubular well fitting in which it fits, locking means carried by said body member and being bodily movable outwardly thereof so that a portion of said locking means projects beyond the surface of said body member toward and into contact with seatingtgroove means in inner surface of said well fitting, and actuating means carried by said body member for operatively engaging said locking means, said actuating means being movable with respect to said body member in response to fluid pressure application thereto, apparatus containing pressure fluid port means in fluid communication on one end with the actuating means in said body member with the other end extending through the wall of said body member and adapted to communicate with a source of pressure fluid.

4. An apparatus for facilitating underwater Wellhead operations which in assembly comprises a vertically projecting tubular well member, a blowout preventer adapted to be mounted on the upper end of said tubular well member, lockdown apparatuses secured to the'top and axial bore therethrough and being of a size to fit into the open lower end of a vertically-disposed well member, outwardly extending shoulder means formed on the. out side of each of said body members,"said shouldermeans having a diameter greater than that of at least aseating portion of the bore of said tubular well member, locking means carried by each of said body members and being bodily movable outwardly thereof so that a portion of said locking means projects beyond the surface of said body member toward and into contact with seating groove means in inner surface of said well member, and actuating means carried by each of said body members for operatively engaging said locking means, said actuating means being movable with respect to said body member in response to fluid pressure application thereto to move said locking means outwardly of said body into locking position with a surrounding well member thereby preventing separation of said body member and said well member, said apparatus f containing pressure fluid port means in fluid communication on one end with the actuating means in said body member with the other end extending through the; wall of said body member and adapted to communicate with a source of pressure fluid.

References Cited by the Examiner UNITED STATES PATENTS 2,862,560v 12/58 Bostock et al 166-217 X 2,906,500; 9/59 Knapp et a1; '166-66.5 2,976,931 3/61 Dafiin Q. 166217 X 2,988,144 6/61 Conrad 16666.5 X 3,002,565 10/61 Moore 166-217 3,032,125 5/62 Hiser et a1 l6666.'5 X

E. QCONNELL, Primary Examiner,

Claims

1. AN APPARATUS FOR FACILITATING UNDERWATER WELLHEAD OPERATIONS WHICH IN ASSEMBLY COMPRISES A VERTICALLY PROJECTING TUBULAR WELL MEMBER, A BLOWOUT PREVENTER ADAPTED TO BE MOUNTED ON THE UPPER END OF SAID TUBULAR WELL MEMBER, A BLOWOUT PREVENTER LOCK-DOWN APPARATUS SECURED TO AT LEAST ONE END OF SAID BLOWOUT PREVENTER COAXIAL THEREWITH, SAID LOCK-DOWN APPARATUS COMPRISING A CYLINDRICAL BODY MEMBER HAVING AN AXIAL BORE THERETHROUGH AND BEING OF A SIZE TO FIT INTO THE OPEN UPPER END OF SAID VERTICALLY PROJECTING TUBULAR WELL MEMBER, OUTWARDLY EXTENDING SHOULDER MEANS FORMED ON THE OUTSIDE OF SAID BODY MEMBER, SAID SHOULDER MEANS HAVING A DIAMETER GREATER THAN THAT OF AT LEAST A PORTION OF THE BORE OF SAID TUBULAR WELL MEMBER IN WHICH IT FITS, LOCKING MEANS MOVABLY CARRIED BY SAID BODY MEMBER AND BEING BODILY MOVABLE OUTWARDLY THEREOF SO THAT A PORTION OF SAID LOCKING MEANS PROJECTS BEYOND THE SURFACE OF SAID BODY MEMBER TOWARD AND INTO CONTACT WITH SEATING GROOVE MEANS IN THE INNER SURFACE OF SAID WELL MEMBER, ANNULAR SEAL MEANS CARRIED OUTWARDLY ON SAID BODY MEMBER ADAPTED TO FORM A FLUIDTIGHT SEAL WITH A SURROUNDING WELL MEMBER, AND ACTUATING MEANS CARRIED BY SAID BODY MEMBER ADAPTED OPERATIVELY ENGAGING SAID LOCKING MEANS, SAID ACTUATING MEANS BEING MOVABLE WITH RESPECT TO SAID BODY MEMBER IN RESPONSE TO FLUID PRESSURE APPLICATION THERETO TO MOVE SAID LOCKING MEAN OUTWARDLY OF SAID BODY MEMBER INTO LOCKING POSITION WITH A SURROUNDING WELL MEMBER THEREBY PREVENTING SEPARATION OF SAID BODY MEMBER AND SAID WELL MEMBER, SAID APPARATUS CONTAINING PRESSURE FLUID PORT MEANS IN FLUID COMMUNICATION ON ONE END WITH THE ACTUATING MEANS IN SAID BODY MEMBER WITH THE OTHER END EXTENDING THROUGH THE WALL OF SAID BODY MEMBER AND ADAPTED TO COMMUNICATE WITH A SOURCE OF PRESSURE FLUID.