(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2014/0332222 A1
`Donald et al.
`(43) Pub. Date:
`Nov. 13, 2014
`
`US 2014-0332222Al
`
`(54) CONNECTION SYSTEM FOR SUBSEA FLOW
`INTERFACE EQUIPMENT
`
`2007, now Pat. No. 8,066,076, filed as application No.
`PC'l‘t'GB2005.’0001r'25 on Feb. 25, 2005.
`
`(71) Applicant: CAMERON SYSTEMS (IRELAND)
`LIMITED, Longford (IE)
`
`(60)
`
`2
`
`-
`
`application No. 60!548,'?27, filed on Feb.
`
`(72)
`
`Inventors: Ian Donald, Aberdeenshjre (GB); John
`Reid, Perthshire (GB); Alan Crawford,
`Aberd
`GB;Pa lW.Whi
`,
`Banchf; EGB;
`“
`“’
`
`(73) Assignee: CANIERON SYSTEMS (IRELAND)
`
`Publication Classification
`
`(51)
`
`Int Cl
`'
`'
`E213 41/00
`(52) U.S. Cl.
`CPC .................................. E213 4170007 (2013.01)
`..........................................................
`
`(2006.01)
`
`(21) App]. No.: 14/232,937
`
`(22) Filed:
`
`May 20, 2014
`
`Related U's' Application Data
`(60) Continuation of application No. 13/267,039, filed on
`Oct. 6, 201 1, now Pat. No. 8,776,891, which is a diVi-
`sion of application No. l0t‘590,563, filed on Dec. 13,
`
`ABSTRACT
`(57)
`A system forconnecting flow interface equipment to a subsea
`manifold is disclosed. The system relates particularly to an
`a
`ratus adapted to inject fluids into a well havin a flow
`big: The system includes a connection apparatus adgapted to
`land a conduit means on a subsea manifold and to connect a
`conduit means ofthe connection apparatus to a choke body of
`the manifold.
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`US 2014/0332222 Al
`
`Nov. 13, 2014
`
`CONNECTION SYSTEM FOR SUBSEA FLOW
`INTERFACE EQUIPMENT
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`[0001] This application is a continuation of U.S. applica-
`tion Ser. No. 131261039 filed Oct. 6, 2011, which is a divi-
`sional ofU.S. application Ser. No. 10r'59D,563 (now U.S. Pat.
`No. 8,066,076) filed Dec. 13, 2007', which is a U.S. National
`Phase Application of PCUGB2005/000725 filed Feb. 25,
`2005, which claims the benefit of U.S. Provisional Applica-
`tion No. 60!548,72'r' filed Feb. 26, 2004, all of which are
`incorporated herein by reference in their entireties for all
`purposes.
`
`BACKGROUND
`
`[0002] This invention relates in general to subsea well pro-
`duction, and in particular to a connection system for connect-
`ing flow interface equipment, such as a pump to a subsea
`Christmas tree assembly.
`
`DESCRIPTION OF RELATED ART
`
`[0003] A subsea production facility typically comprises a
`subs Christmas tree with associated equipment. The subsea
`Christmas tree typically comprises a choke located in a choke
`body in a production wing branch. There may also be a further
`choke located in an annulus wing branch. Typically, well
`fluids leave the tree via the production choke and the produc-
`tion wing branch into an outlet flowline ofthe well. However,
`in such typical trees, the fluids leave the well unboosted and
`unprocessed.
`
`BRIEF SUMMARY
`
`[0004] According to a first aspect of the present invention
`there is provided an apparatus for connecting to a subsea
`wellbore, the wellbore having a manifold and a choke body,
`the apparatus comprising: a frame adapted to land on the
`manifold; a conduit system having a first end for connection
`to the interior of the choke body and a second end for con-
`nection to a processing apparatus; wherein the conduit system
`comprises a conduit means supported by the frame; wherein
`the frame comprises at least one frame member that is adapted
`to land on the manifold in a first stage of the connection and
`wherein the conduit means is adapted to be brought into fluid
`communication with the interior of the choke body in a sec-
`ond stage of the connection.
`[0005] The two-stage connection provides the advantage
`that damage to the mating surfaces between the conduit
`means and the flow line of the tree assembly can be avoided
`whilst the frame is being landed, since at least a part of the
`frame is landed before the connection between the conduit
`means and the interior of the choke body is made up. Hence,
`the two-stage connection acts to bulfer and protect the mating
`surfaces. The two-stage connection also protects the choke
`itself from damage whilst the frame is being landed; in par-
`ticular, the mating surface of the choke is protected.
`[0006]
`In some embodiments, processing apparatus e.g.
`multi-phase flow meters and pumps can be mounted on the
`frame and can be landed on the tree with the frame. Alterna-
`
`tively, the processing apparatus may be located remote from
`the tree, e.g. on a further subsea installation such as a mam-
`
`fold or a pile, and the frame may comprise connections for
`jumper conduits which canlead fluids to and from the remote
`processing apparatus.
`[0007] The processing apparatus allows well fluids to be
`processed (e.g. pressure boostedtirljected with chemicals) at
`the wellhead before being delivered to the outlet flowline of
`the well. The invention may alternatively be used to inject
`fluids into the well using the outlet flowline as an inlet.
`[0008] Often the processing apparatus, e.g. subsea pump, is
`flow meter, etc. is quite heavy and bulky. In embodiments
`where heavy/bulky apparatus is carried by the frame, the risk
`of damage to the mating surfaces between the conduit means
`and the flow line of the tree assembly is particularly great.
`[0009] Optionally, the apparatus further comprises an actu-
`ating means mounted on the frame, the actuating means being
`adapted to bring the conduit means into fluid communication
`with the interior of the choke body. Typically, the actuating
`means comprises at least one hydraulic cylinder. Altema-
`tively, the actuating means may comprise a cable or a screw
`jack which connects the conduit means to the frame, to con-
`trol the movement ofthe conduit means relative to the frame.
`
`[0010] The conduit means is not necessarily brought into
`direct communication with the choke body. In some embodi-
`ments (the first embodiment and the third embodiment
`below), the conduit means is connected with the interior ofthe
`choke body via a fitrther, secondary conduit.
`[0011]
`In a first embodiment, a mounting apparatus is pro-
`vided for landing a flow interface device, particularly a subsea
`pump or compressor (referred to collectively at times as
`“pressure intensifier”) on a subsea production assembly.
`[0012] Optionally, the at least one frame memberofthe first
`connection stage comprises a lower frame member, and the
`apparatus further compri ses an upper frame member, the
`upper frame member and the lower frame member having
`co-operating engagement means for landing the upper frame
`member on the lower frame member.
`
`In the first embodiment, a secondary conduit in the
`[0013]
`form ofa mandrel with a flow passage is mounted to the lower
`frame member. The operator lowers the lower frame member
`into the sea and onto the production assembly. The production
`assembly has an upward facing receptacle that is sealingly
`engaged by the mandrel.
`[0014]
`In this embodiment, the conduit means comprises a
`mamfold, which is mounted to the upper frame member. The
`mamfold is connected to a flow interface device such as a
`
`pressure intensifier, which is also mounted to the upper frame
`member. The operator lowers the upper frame member along
`with the manifold and pressure intensifier into the sea and
`onto the lower frame member, landing the manifold on the
`mandrel. During operation, fluid flows from the pressure
`intensifier through the manifold, the mandrel, and into the
`flow line.
`
`Preferably, the subsea production assembly com-
`[0015]
`prises a Christmas tree with a frame having guide posts. The
`operator installs extensions to the guide posts, if necessary,
`and attaches guidelines that extend to a surface platfonn. The
`lower and upper frame members have sockets with passages
`for the guidelines. The engagement of the sockets with the
`guide posts provides gross alignment as the upper and lower
`frame members are lowered onto the tree frame.
`
`[0016] Also, preferably the Christmas tree frame has
`upward facing guide members that mate with downward fac-
`ing guide members on the lower frame member for providing
`finer alignment. Further, the lower frame member preferably
`
`14
`
`14
`
`

`
`US 2014/0332222 Al
`
`Nov. 13, 2014
`
`has upward facing guide members that mate with downward
`facing guide members on the upper frame member for pro-
`viding finer alignment. One or more locking members on the
`lower frame member lock the lower frame member to the tree
`
`returning from the processing apparatus. Typically, each of
`the two conduits of the conduit means is fixed relative to the
`
`frame at a respective point. Typically, the flexible portion of
`each of the two conduits ofthe conduit means is connected to
`
`frame. Additionally, one or more locking members on the
`upper frame member lock the upper frame member to the
`lower frame member.
`
`[0017] Optionally, the apparatus further comprises buffer-
`ing means provided on the frame, the buffering means pro-
`viding a minimum distance between the frame and the tree.
`[0018] The buffering means may comprise stops or adjust-
`able mechanisms, which may be incorporated with the lock-
`ing members, or which may be separate from the locking
`members.
`
`[0019] The adjustable stops define minimum distances
`between the lower frame member and the upper plate of the
`tree frame and between the lower frame member and the
`upper frame member.
`[0020] The buffering means typically comprise threaded
`bolts, which engage in corresponding apertures in the frame,
`and which can be rotated to increase the length they project
`from the frame. The ends of the threaded bolts typically
`contact the upper frame member of the tree, defining a mini-
`mum distance between the frame and the tree.
`
`[0021] Optionally, a further buffering means is provided
`between the lower and upper frame members to define a
`minimum distance between the lower and upper frame mem-
`bers. The further buffering means also typically comprises
`threaded bolts which extend between the lower and upper
`frame members. The extent ofproj ection ofthe threaded bolts
`can be adjusted to provide a required separation of the upper
`and lower frame members.
`
`[0022] The buffering means (e.g. the adjustable stops) pro-
`vides structural load paths from the upper frame member
`through the lower frame member and tree frame to the tree
`and the wellhead on which the tree is mounted. These load
`
`paths avoid structural loads passing through the mandrel to
`the upward facing receptacle (i .e. the choke body).
`[0023]
`In a second embodiment, the frame is lowered as a
`unit, but typically has an upper portion (an upper frame mem-
`ber) that is vertically movable relative to the lower portion (a
`lower frame member).A processing apparatus (in the form of
`a pressure intensifier) and a conduit means (a mandrel) are
`mounted to the upper portion. An actuating means compri sing
`one or more jack mechanisms is provided between the lower
`and upper portions of the frame. When the lower portion of
`the frame lands on the tree frame, the lower end of the man-
`drel will be spaced above the flow line receptacle. The jack
`mechanisms then lower the upper portion of the frame, caus-
`ing the mandrel to stab sealingly into the receptacle (the
`choke body). Thus, in this embodiment, the conduit means
`comprises a single mandrel having a single flowpath there-
`through.
`In a third embodiment, the conduit means has a
`[0024]
`flexible portion. Preferably, the flexible portion is moveable
`relative to the frame. Typically, the flexible portion of the
`conduit means is fixed relative to the frame at a single point.
`Typically, the flexible portion of the conduit means is con-
`nected to the processing apparatus and supported at the pro-
`cessing apparatus connection, in embodiments where the pro-
`cessing apparatus is supported on the frame.
`[0025] Optionally, the conduit means comprises two con-
`duits, one of which is adapted to carry fluids going towards
`the processing apparatus, the other adapted to carry fluids
`
`the processing apparatus and is supported at the processing
`apparatus connection (where a processing apparatus is pro-
`vided on the frame).
`[0026] Typically, the flexible portion of the conduit means
`is resilient. Typically, the direction of movement of the flex-
`ible portion of the conduit means in the second stage of the
`connection defines an axis of connection and the flexible
`
`portion ofthe conduit means is curved in a plane perpendicu-
`lar to the axis of connection to provide resilience in the
`connection direction. In such embodiments, the flexible por-
`tion of the conduit means is in the form of a coil, or part of a
`coil. This allows the lower end of the conduit means (the
`connection end) to be moved resiliently in the connection
`direction.
`[0027] Typically, the flexible portion of the conduit means
`supports a connector adapted to attach to the choke body
`(either directly or via a further conduit extending from the
`choke body), the flexible portion of the conduit means allow-
`ing relative movement of the connector and the frame to
`buffer the connection.
`
`[0028] Typically, an actuating means is provided which is
`adapted to move the flexible portion relative to the frame to
`bring an end of the flexible portion into fluid communication
`with the interior of the choke body. The actuating means
`typically comprises a swivel eye mounting hydraulic cylin-
`der.
`
`[0029] Considering now all embodiments of the invention,
`the conduit system may optionally provide a single fiowpath
`between the choke body and the processing apparatus.
`[0030] Alternatively, the conduit system provides a two-
`flowpath system: a first flowpath from the choke body to the
`processing apparatus and a second flowpath from the process-
`ing apparatus to the choke body. In such embodiments, the
`conduit system can comprise a housing and an inner hollow
`cylindrical member,
`the inner cylindrical member being
`adapted to seal within the interior of the choke body to define
`a first flow region through the bore of the cylindrical member
`and a second separate flow region in the annulus between the
`cylindrical member and the housing.
`[0031] Typically,
`the first and second flow regions are
`adapted to connect to a respective inlet and an outlet of the
`processing apparatus.
`[0032]
`Such embodiments can be used to recover fluids
`from the well via a first flowpath, process these using the
`processing apparatus (e.g. pressure boosting) and then to
`return the fluids to the choke body via a second fiowpath for
`recovery through the production wing branch. The division of
`the inside ofthe choke body into first and second flow regions
`by the inner cylindrical member allows separation of the first
`and second flowpaths within the choke body.
`[0033]
`Ifused, the housing and the inner hollow cylindrical
`member typically are provided as the part of the conduit
`system that directly connects to the choke body, i.e. in the first
`embodiment, this is the secondary conduit; in the second
`embodiment, the conduit means, and in the third embodi-
`ment, the secondary conduit.
`[0034] Optionally, the processing apparatus is provided on
`the frame. In this case, the processing apparatus is typically
`connected to the conduit means before the frame is landed on
`the tree.
`
`15
`
`15
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`

`
`US 2014/0332222 A1
`
`Nov. 13, 2014
`
`[0035] Alternatively, the processing apparatus is provided
`on a further subsea manifold, such as a suction pile. Jumper
`cables can be connected between the frame on the manifold
`
`lower the mandrel (the conduit means) into connection with
`the choke body in a controlled manner, only after the frame
`has been landed.
`
`and the further subsea manifold to connect the processing
`apparatus to the conduit system. In this case, the processing
`apparatus is typically connected to the conduit means as a
`final step.
`[0036]
`In all embodiments, the frame typically includes
`guide means that co-operate with guide means provided on
`the manifold, to align the frame with the manifold. The frame
`may also or instead comprise a guide pipe that surrounds at
`least a part of the conduit system, to protect it from impact
`damage.
`[0037] All embodiments use the space inside the choke
`body after the choke bonnet has been removed and the choke
`withdrawn. However, it may still be desirable to be able to use
`a choke to control the fluid flow. Optionally, a replacement
`choke is provided on the frame, the replacement choke being
`connectable to the conduit system.
`[0038] Embodiments of the invention can be used for both
`recovery of production fluids and injection of fluids.
`[0039] According to a second aspect of the present inven-
`tion there is provided a method of connecting a processing
`apparatus to a subsea wellbore, the wellbore having a mani-
`fold and a choke body, the method comprising: landing a
`frame on the manifold and connecting a conduit system
`between the choke body and the processing apparatus, the
`frame supporting a conduit means of the conduit system;
`wherein the frame comprises at least one frame member that
`is landed on the manifold in a first connection stage, and
`wherein the conduit means is brought into fluid communica-
`tion with the interior ofthe choke body in a second connection
`stage.
`
`[0040] The method typically includes the initial steps of
`removing the choke bonnet and connecting the secondary
`conduit to interior of the choke body.
`[0041] The choke bonnet is removed and the secondary
`conduit may be installed by choke bonnet changing equip-
`ment (e.g. the third embodiment). Alternatively, the second-
`ary conduit may be supported on the lower frame member and
`may be installed when the lower frame member is landed on
`the manifold (eg. the first embodiment).
`
`[0042] According to a third aspect of the present irtvention
`there is provided an apparatus for connecting to a subsea
`wellbore, the wellbore having a manifold and a choke body,
`the apparatus comprising: a frame having a conduit system,
`the frame being adapted to land on the tree, the conduit system
`including a first end which is adapted to connect to the choke
`body such that the conduit is in fluid communication with the
`interior of the choke body, and a second end connectable to a
`processing apparatus; wherein the frame comprises buffering
`means adapted to buffer the connection between the first end
`of the conduit system and the choke body.
`[0043]
`In the first embodiment, the buffering means may be
`provided by the adjustable stop means, which provide struc-
`tural load paths from the upper frame member through the
`lower frame member and tree frame to the tree and the well-
`head on which the tree is mounted which avoid structural
`
`loads passing through the mandrel to the choke body.
`[0044]
`In the second embodiment, the buffering means is
`typically provided by the arrangement ofthe upper and lower
`frame members, the upper frame member being moveable to
`
`In the third embodiment, the buffering means may
`[0045]
`be provided by the flexible portion of the conduit means,
`which allows movement of the conduit end that connects to
`
`the secondary conduit. Therefore, the connection end of the
`conduit means will not heavily impact into the secondary
`conduit as it is able to deflect as necessary, using the flexibility
`of the conduit means, and can optionally be manoeuvred for
`even greater control (e.g. by an actuating mechanism).
`[0046] According to a fourth aspect ofthe present invention
`there is provided an apparatus for connecting to a subsea
`wellbore, the wellbore having a manifold and a choke body,
`the apparatus comprising: a frame adapted to land on the
`manifold; a conduit system having a first end for connection
`to the choke body and a second end for connection to a
`processing apparatus; wherein at least a part of the conduit
`system is supported by the frame; wherein the conduit system
`comprises at least one flexible conduit having an end that is
`moveable relative to the frame to make up a communication
`between the processing apparatus and the choke body. In such
`embodiments, the end of the flexible conduit can deflect if it
`impacts with the choke body (or any secondary conduit
`extending from the choke body). Thus in such embodiments,
`the flexible conduit ensures that the load carried by the frame
`is not transferred to the choke body.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`invention will now be
`[0047] Embodiments of the
`described, by way of example only, and with reference to the
`following drawings, in which:
`[0048]
`FIG. 1 is an elevational view of a subsea tree assem-
`bly, partially in section, and showing an apparatus for con-
`necting a flow interface to a subsea wellbore;
`[0049]
`FIG. 2 is an enlarged view, partially in section, of a
`choke body of the tree assembly and a lower portion of a
`mandrel of the apparatus of FIG. 1;
`[0050] FIG. 3 is a top view ofthe tree frame of FIG. 1, with
`the connecting apparatus for
`the flow interface device
`removed;
`[0051] FIG. 4 is a top view of a lower frame member of the
`connecting apparatus of FIG. 1;
`[0052] FIG. 5 is a sectional view of the lower frame mem-
`ber of FIG. 4, taken along the line 5-5 of FIG. 4;
`[0053] FIG. 6 is a top view ofan upper frame memberofthe
`connecting apparatus of FIG. 1;
`[0054] FIG. 7 is a partially sectioned view of the upper
`frame member of FIG. 6, taken along the line 7-7 of FIG. 6;
`[0055]
`FIG. 8 is a schematic view of an alternate embodi-
`ment of a connecting system, shown prior to landing on the
`subsea tree assembly;
`[0056] FIG. 9 is a schematic View of the mounting system
`of FIG. 8, with a lower flame member of the connecting
`system landed on the subs tree assembly and the upper
`frame member in an upper position;
`[0057]
`FIG. 10 is a schematic view of the subsea tree
`assembly and the connecting system of FIG. 8, with the upper
`frame member in a lower position;
`[0058]
`FIG. 11 is a side View with interior details of a third
`embodiment of the invention;
`[0059]
`FIG. 12 is an enlarged view in cross-section of a
`portion A of the FIG. 11 embodiment;
`[0060] FIG. 13 is a plan view of the FIG. 11 embodiment;
`
`16
`
`16
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`US 2014/0332222 A1
`
`Nov. 13, 2014
`
`FIGS. 14A, B, C, and D show a series ofviews with
`[0061]
`cross-sectional details showing the FIG. 11 apparatus being
`installed on a manifold;
`[0062]
`FIG. 15 shows an enlarged View of FIG. 14D;
`[0063]
`FIG. 1 6 shows a side view of an embodiment similar
`to that of FIG. 11, the frame also supporting a replacement
`choke; and
`[0064]
`FIG. 17 shows an alternative embodiment similar to
`that of FIG. 16, wherein an actuating means is provided to
`control the movement of a conduit means.
`
`DETAILED DESCRIPTION
`
`[0065] Referring to FIG. 1, production assembly 11 in this
`example includes a subsea Christmas tree 13. Christmas tree
`13 is a tubular member with a tree connector 15 on its lower
`
`end that connects to a wellhead housing (not shown) located
`on the sea floor. Tree 13 may be conventional, having a
`vertical bore with a master valve 17 and a swab valve 19. A
`
`production passage in tree 13 leads laterally to a production
`wing valve 21. Tree 13 may be either a type having a tubing
`hanger landed within, or it may be a type in which the tubing
`hanger lands in the wellhead housing below the tree.
`[0066] A production choke body or receptacle 23 mounts to
`production wing valve 21. Choke body 23 comprises a hous-
`ing for a choke insert (not shown) that is adjustable to create
`a back pressure and a desired flow rate. Choke body 23
`connects to a production flow line 25 that leads to sea floor
`processing equipment or directly to a production facility at
`sea level. After being installed with a pressure intensifier, as
`will be subsequently explained, a choke insert may not be
`required. One use for the connecting apparatus of this inven-
`tion is to retrofit existing trees that have previously operated
`without a pressure intensifier.
`[0067] Tree 13 may also have an annulus valve 2'? that
`communicates with a tubing annulus passage (not shown) in
`the well. An annulus choke 29 connects to annulus valve 27
`
`for controlling a flow rate either into or out of the tubing
`armulus. Armulus choke 29 is normally located on a side of
`production assembly 11 opposite production choke body 23.
`Armulus choke 29 has a body with a choke insert similar to
`production choke body 23.
`[0068] A tree cap 31 releasably mounts to the upper end of
`tree 13. A tree frame 33 extends around tree 13 for mounting
`various associated equipment and providing protection to tree
`13 if snagged by fishing nets. Tree frame 33 is structurally
`connected to the body of tree 13, such that weight imposed on
`tree frame 33 transfers to tree 13 and from thereto the well-
`head housing (not shown) on which tree 13 is mounted. Tree
`frame 33 has an upper frame member portion or plate 35 that
`in this instance is located above swab valve 19 and below tree
`cap 31. Upper plate 35 surrounds tree 13, as shown in FIG. 3,
`and is generally rectangular in configuration. Tree frame
`upper plate 35 has a cutout 36 that provides vertical access to
`choke body 23 and a cutout 38 that provides vertical access to
`annulus choke 29.
`
`[0069] As shown in FIG. 3, preferably tree frame upper
`plate 35 has a plurality of guide members 37. Guide members
`37 may vary in type, and prior to retrofitting with a pressure
`intensifier, were used to land equipment for retrieving and
`replacing the choke insert (not shown) in choke body 23 and
`in annulus choke 29. Although some subsea trees do not have
`any type of guide members, many do, particularly trees
`installed during the past 10-15 years. In this example, each
`guide member 37 comprises an upward facing cylinder with
`
`an open top. Guide members 37 are mounted in pairs in this
`example with a locking member 39 located between them.
`Locking member 39 has a latch that latches onto a locking
`member inserted from above. Four separate sets of guide
`members 37 are shown in FIG. 3, with one set located on
`opposite sides ofcutout 36 and the other sets on opposite sides
`of cutout 38.
`
`[0070] FIG. 3 also shows a control pod receptacle 40 that
`may be conventional. Control pod receptacle 40 has guide
`members 37 and locking members 39 for landing an electrical
`and hydraulic control pod (not shown) lowered from sea level.
`A plurality ofguide posts 41 are located adjacent sides oftree
`frame 33. Typically, each guide post 41 is located at a comer
`of tree frame 33, which is generally rectangular in configu-
`ration. Only one guide post 41 is shown in FIG. 1, but the
`other three are the same in appearance. The existing guide
`posts 41 likely may not be long enough for the retrofit of a
`pressure intensifier in accordance with this invention. If so, a
`guide post extension 42 is installed over each guide post 41,
`and becomes a part of each guide post 41. Guide post exten-
`sions 42 protrude upward past tree cap 31 . A guideline 43 with
`a socket on its lower end slides over and connects to each
`
`guide post 41 or guide post extension 42, if such are used.
`Guidelines 43 extend upward to a platform or workover ves-
`sel at sea level.
`
`[0071] Still referring to FIG. 1, a flow interface device
`lower frame member 45 lands on and is supported by tree
`frame upper plate 35. In this embodiment, lower frame mem-
`ber 45 is a flat generally rectangular member, as shown in
`FIG. 4, but it need not be a flat plate. A mandrel 47 is secured
`to one side of lower frame member 45. Mandrel 47 has a
`
`tubular lower portion with a flange 49 that abuts and seals to
`a mating flange on choke body 23. Alternatively, mandrel 47
`could be positioned on an opposite edge of lower frame
`member 45 and mate with the body of annulus choke 29,
`rather than choke body 23.
`[0072] A clamp 51 locks flange 49 to the flange of choke
`body 23. Clamp 51 is preferably the same apparatus that
`previously clamped the choke insert (not shown) into choke
`body 23 when production assembly 11 was being operated
`without apressure intensifier. Clamp 51 is preferably actuated
`with an ROV (remote operated vehicle) to release and actuate
`clamp 51.
`[0073] Referring to FIG. 2, mandrel 47 has a lower bore 52
`that aligns with choke body vertical bore 53. A retrievable
`plug 55 is shown installed within a lower portion of choke
`vertical bore 53. A lateral passage 57 leads from choke body
`vertical bore 53 above plug 55 to production wing valve 21
`(FIG. 1). Plug 55 prevents fluid flowing down through man-
`drel 47 from entering flow line 25. Some installations have a
`valve in flow line 25 downstream ofchoke body 23. If so, plug
`55 is not required.
`[0074] Referring to FIG. 5, lower frame member 45 has a
`plurality ofguide members 67 on its lower side that mate with
`guide members 37 of tree frame upper plate 35 as show in
`FIG. 3. Only one of the sets of guide members 67 is shown,
`and they are shown in a schematic form. Furthermore, a
`locking member 69 protrudes downward from lower trame
`member 45 for locking engagement with one of the locking
`members 39 (FIG. 3) of tree flame upper plate 35. Lock
`member 69 is also shown schematically. Other types oflocks
`are feasible.
`
`[0075] Lower frame member 45 also has guide post sockets
`71, each preferably being a hollow tube with a downward
`
`17
`
`17
`
`

`
`US 2014/0332222 Al
`
`Nov. 13, 2014
`
`facing funnel on its lower end. Guide post sockets 71 slide
`over guide lines 43 (FIG. 1) and guide posts 41 or extensions
`42. Guide posts 41 or their extensions 42 provide a gross
`alignment ofmandrel 47 with choke body 23 (FIG. 1). Guides
`67 and 37 (FIG. 1 ) provide finer alignment ofmandrel 47 with
`choke body 23 (FIG. 1).
`[0076] Referring still to FIG. 5, lower frame member 45
`also preferably has a plurality of upward facing guide mem-
`bers 75. In this example, guide members 75 are the same type
`as guide members 37 (FIG. 3), being upward facing cylinders
`with open tops. Othertypes ofguide members may be utilized
`as well. In this instance, preferably there are four sets of guide
`members 75, with each set comprising two guide members 75
`with a locking member 77 located between as shown in FIG.
`4. Guide members 75 are located in vertical alignment with
`guide members 37 (FIG. 3), but could be positioned else-
`where. Lower fiame member 45 also has a cutout 79 on one
`
`side for providing vertical access to annulus choke 29 (FIG.
`3).
`[0077] An adjustment mechanism or mechanisms (not
`shown) may extend between lower frame member 45 and tree
`frame upper plate 37 to assure that the weight on lower frame
`member 45 transfers to tree frame upper plate 37 and not
`through mandrel 47 to choke body 23. While the lower end of
`mandrel 47 does abut the upper end of choke body 23, pref-
`erably, very little if any downward load due to any weight on
`lower frame member 45 passes down mandrel 47 to choke
`body 23. Applying a heavy load to choke body 23 could create
`excessive bending moments on the connection of production
`wing valve 21 to the body of tree 13. The adjustment mecha-
`nisms may comprise adjustable stops on the lower side of
`lower frame member 45 that contact the upper side of tree
`frame upper plate 37 to provide a desired minimum distance
`between lower frame member 45 and upper plate 37. The
`minimum distance would assure that the weight on lower
`frame member 45 transfe