US3347311A

US3347311A - Underwater well completion

Info

Publication number: US3347311A
Application number: US302993A
Authority: US
Inventors: Jr William W Word
Original assignee: Armco Inc
Current assignee: Armco Inc
Priority date: 1963-08-19
Filing date: 1963-08-19
Publication date: 1967-10-17
Anticipated expiration: 1984-10-17
Also published as: DE1288536B; GB1076761A

Description

Oct. 17, 1967 UNDERWATER WELL COMPLETION Filed Aug. 19, 1963 4 39 I 33 55 42 5 MN 5r :{g J 48 32 40 %j 49 I 4| I 28 2 x53 4? j 5 1 ss 6 I2 30 I I? I4 INVENTOR ATTORNEY w. w. WORD, JR v 3,347,311 I s Sheets-Sheet; I

i William W.Word,Jr. I

Oct. 17, 1967 w. w. WORD. JR 3,347,311:

' UNDERWATER WELL COMPLETION Filed Aug. 19, 1963 s Sheets-Sheet 2 \i J r 2 92 FIG.2.

I INVENTOR ATTORNEYS William W. Word,Jr.

Oct. 17, 1967 w. w. WORD, JR

UNDERWATER WELL COMPLETION I a Sheets-Sheet 5 Filed Aug. 19, 1963 m V m m .m

ATTORNEYS Oct 17, w w WORD, JR UNDERWATER WELL COMPLETION Filed Aug. 19, 1965 8 Sheets-Sheet 5 FIG.5.

INVENTOR William w. Word,Jr.-

ATTORNEYS Oct. 17, 1967 w. w. WORD, JR 3,347,311

UNDERWATER WELL COMPLETION Filed Aug. 19, 1963 8 Sheets-Sheet 6 FIG 7 I ATTORNEYS Oct. 17, 1967 Filed Aug. 19, 1963 W. W. WORD, JR

UNDERWATER WELL COMPLETION ZIO 8 Sheets-Sheet 7 I, Zl5 I6 I i '4 v 2|9 I 2n- 2l4 i "2 g 220 22:

F I G INVENTOR William W.Word.Jr.

ATTORNEYS 8 Sheets-Sheet 8 Oct. 17, 1967 w. w. WORD, JR

UNDERWATER WELL COMPLETION Filed Aug. 19, 1963 R m. m m Mm m o w W in United States Patent 3,347,311 UNDERWATER WELL COMPLETION William W. Word, In, Houston, Tex., assignor to Armco Steel Corporation, Middletown, Ohio, a corporation of Ohio Filed Aug. 19, 1963, Ser. No. 302,993 7 Claims. (Cl. 166-.6)

This invention relates to underwater well completion and more particularly to underwater wellhead constructions embodying an improved production unit assembly.

Wellhead installations require, for completion of the well, means for attaching the Christmas tree to the subadjacent wellhead body and completing the production flow lines, usually with provision for reentry into the well. In dry land installations, many such arrangements have been developed and found satisfactory in use. In wellhead constructions assembled under water, at points remote from the drilling vessel or platform, problems are encountered which make the usual dry land apparatus impractical. Thus, for example, a completed underwater well normally involves a flow line or lines connected at one end to the production unitof the wellhead, the lines running under water for considerable distances and frequently being buried in silt, etc. Because of this condition, .the flow lines cannot necessarily be recovered in the event of failure of the flow lines or a failure in the production unit of the wellhead.

Further, while wellhead connections in a dry land installation are relatively simple, since most parts of the wellhead can be observed and handled directly by the operators, underwater wellheads are vastly more complicated, particularly because various devicm in the wellhead must be of the remotely actuated type, involving hydraulic pressure fluid lines, for example, which must extend from the wellhead to a control point. Thus, in underwater installations, it is necessary to provide not only for remotely making and breaking the flow line or lines but also for remotely making and breaking the hydraulic pressure fluid lines.

A general object of this invention is to provide an underwater wellhead construction having a production unit assembly which provides for simpler and more dependable underwater operation.

Another object is to devise, in such a wellhead construe tion, improved means for accommodating and orienting the flow line or lines and the hydraulic control lines.

.A further object is to provide such a wellhead construction which allows the Christmas tree to be recovered in one operation without disturbing the flow line or lines, save for disconnection thereof from the Christmas tree.

Yet another object is to provide such a wellhead construction which allows installation of a new flow line or flow lines, in event of failure of the line or lines already installed, without requiring handling of the original flow line or lines.

A still further object is to provide, in a wellhead construction of the type describe-d, means whereby one or more reserve fluid pressure control lines, present at the time of original installation of the wellhead, can be employed in event of failure of the fluid pressure control .line or lines first employed.

Stated generally, the objects of the invention are achieved by incorporating in the wellhead assembly an additional body member, termed a production body, which member is seated and locked, the production body having an internal passage through which the flow lines or ducts extend to the Christmas tree, the external flow line or 3,347,311 Patented Oct. 17, 1967 lines and the fluid pressure control lines extending upwardly through the production body in locations outside of the internal passage and being connected to; the Christmas tree via connector means carried by the lowermost Christmas tree member. The arrangement is such that all of the flow line and control line connections are made and broken automatically simply by attachment of the lowermost Christmas tree member to the top of the production body, an operation which is accomplished simply by landing the lowermost Christmas tree body and operating a hydraulic control drive.

Since all lines leading from the wellhead, including the flow line or lines and the control lines, but excluding reentry lines, terminate at the production body, the entire Christmas tree can be recovered simply by breaking the joint at the top of the production body and raising the Christmas tree. In event of flow line failure, the Christmas tree can be recovered, a second production body with new flow and control lines installed on top of the original production body, and the Christmas tree reinstalled on top of the second production body.

In order that the manner in which the aforementioned objects are achieved in accordance with. the invention can be understood in detail, reference is had to the accompanying drawings, which form a part of this specification, and wherein:

FIGS. '1-3 combine to provide a view, partly in vertical section and partly in elevation, of a wellhead construction in accordance with one embodiment of the invention;

FIG. 4 is a transverse sectional view taken on line 44, FIG. 1;

FIG. 5 is a fragmentary, enlarged vertical sectional view taken on line 5-5, FIG. 4;

FIG. 6 is :a top plan view of the wellhead construction shown in FIGS. 1-3

FIG. 7 is a vertical sectional view of a portion of the wellhead construction of FIGS. 1-3, modified for installation of a second set of flow lines;

'FIGS. 8 and 9 combine to provide a view, partly in vertical section and partly in elevation, of a wellhead construction in accordance with another embodiment of the invention; and

FIG. 10 is a transverse sectional view taken on line 1010, FIG. 9, FIG. 6 being on smaller scale than FIGS. I3 and the

conduits

103 and 105 being distorted in elevation in FIGS. 2 and 3 for simplicity of illustration.

Referring now to the drawings in detail and first to FIGS. 1-3 thereof, the wellhead installation here illustrated includes a lower, unitary body member 1 seated on a stub body 2 and clamped thereto, as by a conventional ring clamp 3. Body 2 is supported by a landing plate 4 which in turn is supported by the upper end of the outer casing 5. Body member 1 can take any suitable form and, for example, may be constructed in accordance with copending application Serial No. 302,974, filed concurrently herewith by William W. Word, Jr., and now US. Patent 3,268,243. Body member 1 is a unitary tubular structure having at its upper end a flat transverse face 6 and an outwardly opening transverse annular locking groove 7. It will be understood that the body member 1 encloses and supports the various casing hangers (not shown) in usual fashion.

Seated directly on body member 1, and clamped thereto by a connector indicated generally at 8, is a production body 9. Body 9 has a transverse annular lower end face 10 engaged directly with upper end face 6 of body 1. Inwardly of

faces

6 and 10, body members 1 and 9 have cooperating downwardly and inwardly slanting frustoconical surfaces between which is wedged, under axial pressure, a conventional metal sealing ring 11. Hydraulically actuated by pressure fluid supplied via control line 12, coupling 8 includes lock elements 13 adapted for engagement in groove 7 when the actuator ring 14 is forced downwardly by pressure fluid supplied to annular space 12a. Though the coupling 8 can take various forms, it is advantageously of the type fully described and claimed in copending application Serial No. 264,195, filed March 11, 1963, by Claude R. Neilon, Michael A. Walker and William W. Word, Jr., now Patent 3,228,715, issued January 11, 1966. It will be understood that the effect of coupling 8 is to apply axial clamping pressure to body members 1 and 9 so that the lower end of body member 9 is rigidly connected to the upper end of body member 1 and a good fluid-tight seal is established at 11.

Body member 1 has a vertical through passage 15. Body member 9 has a vertical through passage 16 aligned coaxially with passage 15. At the lower end of body memher 9, an upwardly directed downwardly and inwardly slanting frusto-conical shoulder 17 is provided to support the dual string tubing hanger 18. Hanger 18 is provided with a pair of vertical through bores 19 and 20. Bore 19 accommodates mandrel 21 which is rigidly supported by a transverse annular shoulder 22 in bore 19, the lower end of mandrel 21 being internally threaded for attachment to tubing string 23. Bore accommodates a mandrel 24 seated on shoulder 25 and internally threaded at its lower end for attachment to tubing string 26.

Commencing a short distance above shoulder 17, passage 16 includes a portion of slightly enlarged diameter accommodating a guide sleeve 27 which is rigidly affixed, as by welding, to body member 9. Constructed and employed generally in accordance with Patent 3,097,695, issued July 16, 1963, to Robert K. LeRouax et al., guide sleeve 27 has a downwardly slanting guide surface '28 leading to a vertical locator notch or slot 29 which extends to the bottom of the sleeve. The upper portion 30 of hanger 18 is of such outer diameter as to fill the surrounding passage 16 and is provided with a rigidly fixed locator lug 31 which is dimensioned to be received in slot 29 and projects radially outwardly from portion 30 so that, as the hanger descends into passage 16, lug 31 first engages guide surface 28 and travels therealong until it comes to rest within notch 29. Accordingly, lug 31 and sleeve 27 coact to locate hanger 18 in a predetermined rotational position within body member 9 as the hanger is landed, and this position determines the rotational positions of mandrels 21 and 24.

At its upper end, body'member 9 has an outwardly projecting transverse annular flange 32 which, though of substantial axial dimension, occupies only a small portion of the total length of body member 9. Flange 32 presents a flat transverse annular upwardly directed end face 33 and is formed with an outwardly opening transverse annular locking groove 34. Commencing at the inner edge of end face 33 is a downwardly and inwardly :slanting frusto-conical surface 35 adapted to support a "sealing ring as later described.

As will be clear from a comparison of FIGS. 1 and 4, the flange 32 is provided with two larger vertical bores 36 and 37. Bore 36 accommodates a rigid cylindrical conduit member 38 having-an upper end portion 39 projecting upwardly above end face 33. Conduit member 38 also includes a lower end portion 40 which projects below flange 32 and is welded to flow line 41. Member 38 is rigidly secured to flange 32, as by welding, at the bottom of the flange. Bore 37 accommodates a rigid conduit member 42 identical with conduit member 38, the lower end portion of member 42 being welded to the second flow line 43.

Extending beside each of

flow lines

41 and 43 are primary hydraulic control lines 44 which are connected to operate the master valves and wing valves of the Christmas tree assembly later described. Advantageously, the control lines 44 include at least one reserve control line, that is, a control line in excess of the number actually required for operation of the wellhead devices. Advantageously, a complete duplicate set of the control lines *44 is included. Flange 32 is provided with a plurality of vertical bores 45 adequate in number to accommodate all of the hydraulic control lines which must be passed through the flange. Each bore 45 has an enlarged upper cylindrical portion 46 which opens through the upper end face 33.

The upper end of body member 9 is closed by a closure body indicated generally at 47 which is locked to body member 9 by hydraulically actuated coupling 48, coupling 48 again being constructed as disclosed and claimed in copending application Serial No. 264,195, filed March 11, 1963, by Claude R. Neilon, Michael A. Walker and William W. Word, I r. Closure body 47 includes a dependent cylindrical portion 49 and a transverse annular outwardly projecting upper flange 50. Flange 50 has a downwardly directed transverse annular flat face 51 adapted to seat directly on the upwardly directed end face 33 of flange 32. Portion 49 has a diameter adequate to substantially fill the space defined in passage 16 by sleeve 27 and is provided with a pair of vertical parallel bores 52 and 53 which extend entirely through the closure body and are disposed for coaxial alignment with tubing hangers 21 and 24, respectively. Dependent portion 49 has an outwardly projecting rigidly fixed lug 54 dimensioned to be received in locator slot 29. Hence, as the closure body is landed, lug 54 rides down guide surface 28 and enters slot 29 orienting the closure body in a predetermined rotational position, relative to production body member 9, such that bores 52 and 53 are aligned coaxially with mandrels 21 and 24, respectively. At the inner edge of surface 51, body 47 has a downwardly and inwardly slanting frusto-conical surface 55, and a metal sealing ring 56 is wedged between surfaces 35 and 55, with axial sealing pressure being maintained by the coupling 48.

The lower end of bore 52 is interiorly threaded to receive a connector 57, the lower end portion of connector 57 engaging within the upper end of mandrel 21 as the closure body is landed. Similarly, the lower end of bore '53, interiorly threaded for attachment of connector 58, engages in the upper end portion of mandrel 24. Hence, though the tubing strings 23 and 26 are suspended from the production body 9 via hanger .18 and mandrels 21 and 24, respectively, bores 52 and 53 communicate with the respective tubing strings once the closure body has been installed.

Flange 50 is provided with two vertical bores '59 and 60 which accommodate rigid cylindrical connector tubes 61 and "62, respectively, the connector tubes being rigidly aflixed to flange 50 by welding, as shown. .At its lower end, connector tube 61 has an enlarged internal diameter and is provided with sealing rings to receive in sealed relation the projecting upper end portion 39 of member 38. Connector tube 62 is similarly constructed to receive the projecting upper end portion of member 42. In this regard, it will be understood that the cooperation between lug 54 and the guide surface 28 and slot 29 serves to assure that

tubes

61 and 62 will be properly positioned rotationally to receive

members

38 and 42, respectively, as flange 50 comes into engagement with flange '32.

Flange 58 is also provided with a plurality of vertical bores 63 equal in number to the bores 45 in flange 32. Bores 63 are so located that, when body 47 has been fully landed, with lug 54 engaged in slot 29, each bore 63 will be coaxially-aligned with a different one -of the bores 45.

The enlarged upper portion 46 of each bore 45 accommodates the lower end of an upright check valve body 64. The lower end of body 64 is tubular and interiorly threaded, being engaged with the exteriorly threaded upper end of the corresponding conduit 44. Body 64 projects upwardly above surface 33 and is generally tubular, defining an upwardly and inwardly tapering valve seat 65, an intermediate chamber 66, and a threaded bore 67. A movable valve member 68, with an outer frusto-con'ical surface matching surface '65, .is urged upwardly toward surface 65 by a spring 69 engaged between the movable valve element and an exteriorly threaded stop member 70 provided with a plurality of axially extending bores 71. It will be apparent that spring 69 normally urges valve element 68 into its closed position, engaging surface 65. When valve element 68 is in its lower, open position, however, pressure fluid supplied via conduit 44 can pass through bores 71 and around valve element 68, discharging upwardly from member 64.

Each bore 63 accommodates a tubular body 72 having at its lower end a cylindrical downwardly opening recess 73 dimensioned to receive and snugly embrace the projecting upper end portion of the corresponding body 64. The side wall of recess 73 is grooved to accommodate sealing rings 74 to provide a fluid-tight seal between members 63 and 64. Immediately above recess 73, body 72 defines a downwardly and inwardly slanting frustoconical valve seat 75, an inter-mediate chamber 76 and a threaded bore 77 being located thereabove. A movable valve element 78, having a downwardly and inwardly slanting frusto-conical surface matching seat 75, is disposed above the valve seat, being urged downwardly by a spring 79 engaged between the movable valve element and a stop member 80 secured in bore 77. Movable valve element 78 includes a dependent pin portion 81 adapted to engage the upper end of movable valve element 68. The length of pin 81 is so chosen that, when faces 50 and 33 are engaged, upon landing of the closure body 47, engagement of pin 81 with valve element 68 will cause both valve elements 68 and 78 to be moved away from their corresponding valve seats, so that hydraulic pressure fluid supplied from conduit 44 may pass upwardly through body 72.

One end of a conduit 82 is disposed within the upper end of body 72, and stop member 80 is provided with a plurality of axially extending. bores 83 to pass fluid to or from the conduit 82.

It will be understood that body 72 is rigidly secured to flange 50, as by welding at 84, and that the conduit 82 is similarly secured to body 72, as by welding at 85.

Whenever flange 50 is separated from flange 32, so that pin 81 no longer engages valve element 68, valve elements 68 and 78 are forced into engagement with seats 65 and 75, respectively, sealing ofl both

conduits

44 and 82.

Flange 50 presents a flat transverse upper face 86 through which bores 59, 60 and 63 open. At the upper ends of each bore 52 and 53, the closure member is recessed to receive sealed

connector devices

87 and 88, respectively,

devices

87 and 88 being constructed in accordance with US. Patent 3,062,565, issued Nov. 6, 1962, to William W. Word, Jr. Surrounding the location of

devices

87 and 88 is an upwardly opening groove which accommodates a conventional sealing ring 89.

Closure member 47 supports a multiple port hydraulically operated fail-safe closed master valve of conventional type, indicated generally at 90. The bottom flange 91 of the master valve is recessed to seat on sealing ring 89 and is clamped in place by bolts 92, in the usual fashion. Bolted to the upper flange 93 of master valve 90 is the base flange 94 of a multiple port flow line fitting 95.

The lower portion of fitting 95 is provided with two

parallel bores

96 and 97 which extend coaxially with

bores

52 and 53, respectively, and communicate respectively with the outlet of the master valve 90.

Bores

96 and 97 open through the upper end of fitting 95 and, in the upper portion of the fitting, accommodate combination plug and flow

line diverter devices

98 and 99, respectively. Fitting 95 has a laterally enlarged intermediate body portion 100 in which are formed upwardly and outwardly slanting side ports -1 and 102. The lower end of port 101 opens into bore 96 below the plug and di- 'verter 98, and the upper end of port 101 receives one end of a conduit 103 which is fixed to portion 100 of the fitting, as by welding at 104. The lower end of port 102 opens into bore 97 below device 99, the upper end of 'port 102 receiving one end of a conduit 105 which is rigidly secured to body portion 100, as by welding, at 106. The portion of conduit 103 adjacent fitting is supported and stabilized by a brace 107 secured to the upper flange of the fitting. In identical but complementary fashion, the corresponding portion of conduit 105 is supported by brace 108.

The other end portion of conduit 103 passes downwardly through the vertical bore of a bracket 107 which is secured to and projects laterally from the bottom flange 94 of fitting 95, the bore of bracket 107 being aligned vertically above connector element 62.. Disposed between bracket 107' and connector element 62 is a hydraulically operated fail-safe wing valve 108' having one of its ports connected to the end of conduit 103 and the other of its ports connected to element 62 by a short conduit 109. The remaining end portion of conduit 105 extends downwardly through the vertical bore of a bracket 110 which is fixed rigidly to flange 94 at a point diametrically opposite bracket 107. Bracket 110 is disposed with its vertical bore in'alignment with connector element 61. A bydraulically operated fail-safe wing valve 111 is connected between conduit 105 and a short length of pipe 112, the latter being received in and rigidly attached to the upper end of element 61. Accordingly, with the wellhead assembled as shown, flow line 41 is connected, via wing valve 111, conduit 105, side port 102, bore 97 of fitting 95, the corresponding portion of master valve 90, bore 53 and mandrel 24, to tubing string 26. Similarly, flow line 43 is connected via wing valve 108, conduit 103, side port 101, bore 96, the corresponding portion of master valve 90, bore 52, and mandrel 21, to tubing string 23.

Flow lines

41 and 43 are attached to the flange 32 of production body 9 before that body is installed. The Christmas tree, including closure body 47, master valve 90, fitting 95,

conduits

103 and 105, and wing valves 108 and 111, is, of course, preassembled and installed as a unit. A primary advantage of the invention is the fact that the Christmas tree assembly can be installed and retrieved, with appropriate operation of coupling 48, without requiring any special manipulation to accomplish connection of the

flow lines

41 and 43 to the Christmas tree assembly.

Referring to FIGS. 1-3 and 6', it will be observed that the

conduits

103 and 105 are disposed generally in the form of loops which involve only relatively large radii of curvature. Thus, conduit 103 passes first upwardly beside the body of fitting 95, then gradually outwardly away from the vertical axis of the Christmas tree still in the same general plane of curvature. Conduit 103 then curves toward the viewer, as FIGS. 1-3 are seen, and then passes to the opposite side of the Christmas tree assembly, curving gradually back into the original plane of curvature and downwardly toward side port 101. Commencing from a point diametrically opposite to that from which conduit 103 started, conduit 105 follows a similar but complementary gradually curving path. Arranged in this fashion, and taking into consideration the normal height of the wellhead assembly,

conduits

103 and 105 can be installed without requiring them to have a radius of curvature less than five feet for example. This allows the use of relatively long well service tools which otherwise would tend to jam during their passage through

conduits

103 and 105.

Secured to the upper flange of fitting 95 is a conventional hydraulically operated port fail-safe swab valve .115 which, in turn, supports the Christmas tree top adapter fitting 116. Fitting 116 is closed by a top closure member 117 locked down to fitting 116 by a hydraulically 120 has a downwardly facing guide surface 121 which slants upwardly to a vertical locator slot 122. The body of adapter 116 is provided with a laterally projecting locator pin 123 dimensioned to be received in slot 122, Upon installation of the reentry connector 118, pin 123 and surface 121 and slot 122 coact to rotationally orient connector 118 and body 117 to assure proper alignment of the

tubing risers

124 and 125 with the tubing hanger mandrels. The body of adapter 116 is provided with a plurality of bones, one of which is indicated at 126, which are each connected to a different hydraulic flow riser 127 via a double acting check valve connector indicated diagrammatically at 128 and constructed in the same general fashion illustrated in FIG. 5. The bores 126 communicate with hydraulic control lines, such as line 129, for operation of the

coupling

8 and 48, as well as the master valve 90, the wing valves 108 and 109 and the swab valve 115. Bore 126 and communicating hydraulic line 129 also combine with a suitable conventional hydraulic relay device (not shown) to provide a secondary, overriding means for hydraulic operation of the master valve 90, swab valve 115 and wing valves 108 and 111.

Just as the locator means comprising sleeve 120 and pin 123 in the reentry connector assure proper connection for the hydraulic control lines on reentry, the locator means comprising sleeve 27 and lug 54 assures proper connection through coupling 48 of the hydraulic control lines 12 required to operate elements of the wellhead below coupling 48. With the wellhead constructed as illustrated, the minimum requirement for control line connections through flange 32 and flange 50 is one primary control line for each tubing string and two control lines necessary for operating the lower coupling 8. As seen in FIG. 4, however, provision is made for six of the double check valve connector units of FIG. 5, two of the bores 63 being closed by suitable plugs so that only four connections are completed in the fashion seen in FIG. when the closure body 47 is landed, even though a total of four primary control lines 44 are installed with production body 9. Those of the bores 63 in flange 50 of closure member 47 which are not to be used at the time of initial installation of the closure body are closed by suitable plugs. Then, in the event of failure of one or more of the primary hydraulic control lines, and after having suitably plugged the bores of

tubings

23 and 26 at some distance below mandrels 21 and 24, coupling 48 is disconnected, the Christmas tree recovered, the plugs removed from appropriate ones of the bores 63 and replaced by upper valve assemblies of the type seen in FIG. 5, the bores 63 corresponding to the faulty hydraulic lines then being closed, and the Christmas tree then reinstalled.

In the event of flow line failure under circumstances where recovery of the

flow lines

41 and 43 is impractical, a second production body, comprised of upper body portion 9a and lower body portion 9b, is installed on top of the body 9, as seen in FIG. 7, this second production body 9a and 912 being equipped with new flow lines 41a and 43a as well as new primary hydraulic control lines 44a. This

second production body

9a and 9b is, of course, equipped with a hydraulically actuated coupling 48a, constructed in the same fashion as coupling 48. Closure member 47, FIG. 1, is removed and the depending portion of

body

9a and 9b is landed in the same fashion as the closure member it replaces by means of the locator sleeve 27 and slot 291). Body 9a is positioned so that groove a in its lower face accommodates the upper portion of

flow lines

41 and 43, as well as the upper portions of hydraulic control lines 64, which have failed. A new closure 47a is then installed in the Christmas tree assembly, being positioned into place internally to body 911 in the same fashion as body portion 9b, using slanting guide surface 28a, sleeve 27a, slot 29a, and lug 54a, as shown. The Christmas tree is then again lowered into place and coupling 48a employed to lock the upper end 8 of production body 9a in the same fashion as coupling 48 has been employed to lock body 9.

FIGS. 8-10 illustrate a wellhead assembly in accordance with another embodiment of the invention wherein the tubing hanger is supported in the lower wellhead body member, rather than in the production body, and a simplified flow line arrangement is employed in the Christmas tree assembly.

Here, the lower wellhead body member 200, in addition to supporting the usual casing hangers and like internal wellhead elements, supports the dual string tubing hanger 201 and includes a guide sleeve 202, the hanger 201 having a locator lug 203 cooperating with the sleeve to assure that the hanger will be disposed in a predetermined rotational position with respect to body 200. Production body 204 is supported by the upper end of lower body member 200 and is locked thereto by a hydraulically actuated coupling 205 of the type disclosed in the aforementioned copending application Serial No. 264,195. Production body 204 includes a dependent portion 206 disposed in the upper end of the passage of body member 200 and therefore within the guide sleeve 202. Portion 206 of production body 204 is provided with a radially projecting locator lug 207 which cooperates with the locator slot in guide sleeve 202 to assure that the

bores

208 and 209 of the production body are properly oriented rotationally with respect to the tubing hanger mandrels supported by hanger 201.

The upper end of production body 204 is closed by a closure member 210 which is seated on body 204 and locked thereto by a hydraulic actuated coupling 211. The passage of body 204 is provided with a guide sleeve 212 having a locator slot which receives the laterally projecting locator lug 213 carried by the dependent portion 214 of closure body 210. Accordingly, the

bores

215 and 216 of closure body 210 are automatically brought into alignment with the

bores

208 and 209, respectively, of production body 204.

Flow lines

217 and 218 are attached to the closure body 210 in the same fashion hereinbefore described with reference to FIGS. 1-3. Thus, flow line 217 is connected to an upright tubular connector 219 which extends vertically through and is rigidly attached to the flange 220 of the closure body. Flow line 218 is similarly connected to element 221. The primary hydraulic control lines 222 also terminate in connectors (not shown) carried by flange 220, these connectors being constructed in accordance with FIG. 5. Closure body 210 has an upper flange 223 provided with suitable bores which, because of the coaction between locator lug 213 and guide sleeve 212, register automatically with the respective ones of

elements

219 and 221. Flange 223 of course also carries the appropriate number of hydraulic control line connectors (not shown) as will be understood from FIG. 5.

Closure body 210 forms the lower element of a Christmas tree assembly including a hydraulically operated fail- :safe master valve 224, a multiport flow line fitting 225, a hydraulically operated fail-safe swab valve 226, a top adapter fitting 227, and a closure body 228 which is locked to fitting 227 by a hydraulically actuated reentry cou- .pling 22 9.

Fitting 225 is provided not only with through bores but also with two side ports each communicating with a different one of the through bores, it being understood .that the through bores of fitting 225 are aligned respectively with the two tubing strings. Connected respectively to the side ports of fitting 225 are conduits .230 and 231 which extend in semicircular fashion and are disposed in a common horizontal line. At their ends opposite fitting 225,

conduits

230 and 231 are interconnected via a hydraulically operated fail-safe flow line valve 232. Adjacent valve 232, conduit 230 is provided with a T-connection from which a short length of pipe 233 depends, being connected to a hydraulically operated fail-safe wing valve 234. The remaining port of valve 234 is connected to a short length of pipe 235 which is welded to flange 223 of the closure body and is aligned with and in communication with the connector tube 219 of flow line 217. Conduit 231 is similarly provided with a T-connection adjacent valve 232 from which depends a short length of pipe 236 connected to one port of a hydraulically operated fail-safe wing valve 237. The remaining port of valve 237 is connected to a short length of pipe 238 welded to flange 223 and in communication with connector tube 221 of flow line 218. A ball diverter, indicated at 240, is disposed in conduit 230 adjacent the T-connection for pipe 233 and is-oriented to prevent balls or like cleaning devices from entering conduit 230. Similarly, a ball diverter, indicated at 241, is disposed in conduit 231 adjacent the T-connection for pipe 236 and is oriented to prevent balls and the like from entering conduit 231.

If flow line 217 should be plugged, master valve 224 is closed, valve 232 is opened, and a cleaning ball or the like is inserted in flow line 218 and pumped through that line, pipe 238, valve 237 and pipe 236, then being deflected by deflector 241 to travel through valve 232. Deflector 240 then directs the ball down pipe 233, so that the ball is forced through valve 234 and pipe 235 into flow line 217. With master valve 224 closed and valve 232 open, a ball or other cleaning device can follow the same course just described, but in the opposite direction, when pumped through flow line 217 toward the wellhead.

While advantageous embodiments of the invention have been chosen to illustrate the same, various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims.

What is claimed is: t

1. In an underwater wellhead construction, the combination of upright wellhead body means having a vertical through passage accommodating at least one production string, and

upwardly facing shoulder means disposed at the upper end of said body means;

a Christmas tree assembly comprising a base member seated on said upwardly facing shoulder means and having a vertical through passage,

flow passage means placed in communication with said production string when said base member is seated on said upwardly facing shoulder means,

a plurality of vertical upper flow devices secured to said base member outwardly of said through passage therein, and

production conduit means interconnecting said production string and one of said upper flow devices via said flow passage means;

at least one production flow line for conveying product away from the wellhead,

said production flow line having an end portion secured to said wellhead body means outwardly of said through passage therein and in a location below said upwardly facing shoulder means, said flow line extending downwardly and thence away from said wellhead body means; and

a plurality of vertically disposed lower flow devices secured to said wellhead body means,

one of said lower flow devices communicating with and extending upwardly from said production flow line,

said lower flow devices communicating respectively with said upper flow devices, whereby said production flow line communicates with said production conduit means, and thus with said production string, via said one upper flow device and the corresponding one of said lower flow devices.

2. An underwater Wellhead construction according to claim 1, wherein at least one of said wellhead body means and said base member has an outwardly projecting transverse flange located above said end portion of said production flow line and in the area occupied by like ones of said flow devices, such flow devices extending through said flange.

3. In an underwater wellhead construction, the combination of an upright wellhead body member having a vertical through passage accommodating at least one production string, and an upper transverse outwardly projecting flange;

at least one production flow line and at least one fluid pressure control line,

each of said lines being attached to said wellhead body member outwardly of said passage,

said wellhead body member having a plurality of vertically disposed lower flow devices each communicating with and extending upwardly from a different one of said lines, said flow devices being spaced in an annularseries about said passage and extending through said flange;

a Christmas tree assembly comprising a base member adapted to seat on said wellhead body member and having a vertical through passage,

flow passage means placed in communication with said production string when said base member is seated on said wellhead body member,

a plurality of vertical upper flow devices carried by i said base member outwardly of said through passage therein and arranged in a spaced annular series corresponding to said first-mentioned series,

fluid pressure-operated valve means connected to control production fiow through said flow passage means,

production conduit means interconnecting said flow passage means and one of said upper flow devices and valve control conduit means connected to another of said upper flow devices;

cooperating locator means carried by said wellhead body member and said base member and operative to rotationally position said base member with corresponding ones of said upper and lower flow devices vertically aligned; and

remotely actuated connector means operative to lock said base member to said wellhead body member.

4. A wellhead construction in accordance with claim 3 and wherein said base member is a closure body having a transverse outwardly projecting flange, and said upper flow devices extend through said last-mentioned flange.

5. A wellhead construction in accordance with claim 3 and wherein said fluid pressure control lines number at least one more than the total of control lines necessary to control the fluid pressure-operated devices of said Christmas tree assembly.

6. In an underwater wellhead construction, the combination of an upright wellhead body member having a vertical through passage accommodating at least one production string;

at least one production flow line and at least one fluid pressure control line,

said wellhead body member having a plurality of vertically disposed lower flow devices each communicating with and extending upwardly from a diflerent one of said lines, said flow devices being spaced in an annular series about said passage;

a plurality of vertical upper flow devices carried by 1 1 said base member outwardly of said through passage therein and arranged in a spaced annular series corresponding to said first-mentioned series,

fluid pressure-operated valve means connected to control production flow through said flow passage means, production conduit means interconnecting said flow passage means and one of said upper flow devices and valve control conduit means connected to another of said upper flow devices;

said Christmas tree assembly including a flow line fitting having a side port, said one of said upper flow devices to which said production conduit means is connected being disposed on the other side of the central axis of the Christmas tree assembly from said side port,

said production conduit means extending upwardly in a loop and terminating at said side port;

7. In an underwater wellhead construction, the combination of an upright wellhead body member having a vertical through passage accommodating two production strings;

two production flow lines and at least one fluid pressure control line,

said wellhead body member having a plurality of vertically disposed lower flow devices, two of said flow devices each communicating with and extending upwardly from a difierent one of said production flow lines, another of said flow devices communicating with and extending upwardly from said control line, said flow devices being spaced in an annular series about said passage, with said two flow devices spaced diametrically across said through passage;

a Christmas tree assembly comprising a base member adapted to seat on said wellhead body member and having two through passages each communicating with a different one of said production strings,

fluid pressure-operated valve means connected to con? trol production through said two through passages,

a flow line fitting having two diametrically opposed side ports each communicating with a different one of said two through passages,

a plurality of vertical upper flow devices carried by said base member outwardly of said two through passages and arranged in a spaced annular series corresponding to said first-mentioned series,

production conduit means connecting said two side ports each to a different one of said upper flow devices, the two of said upper flow devices to which said side ports are connected being spaced apart diametrically across the vertical axis of said Christmas tree assembly, each of said two upper flow devices being located on the opposite side of said Christmas tree assembly from the side port to which it is connected, and

valve control conduit means connected to another of said upper flow devices;

cooperating locator means carried by said wellhead body member and said base member and operative to rotationally position said base member with cor.- responding ones of said upper and lower flow devices vertically aligned; and

References Cited UNITED STATES PATENTS 3,052,299 9/1962 Geer et a1. l66 .6 3,064,735 11/ 1962 Bauer et a1. 1.66.6 3,097,695 7/1963 Johnson 166-.6 3,155,175 11/1964 Johnson l66.5 X 3,217,805 11/1965 Howard 166--. 6 3,219,117 11/ 1965 Johnstone et al. 16.6-..5 3,222,089 12/1965 Otteman 166+.6 X 3,233,667 2/1966

VanWinkle

16,6-.6

CHARLES E. OCONNELL, Primary Examiner.

R. E. FAVR EAU, Assistant Examiner.

Claims

1. IN AN UNDERWATER WELLHEAD CONSTRUCTION, THE COMBINATION OF UPRIGHT WELLHEAD BODY MEANS HAVING A VERTICAL THROUGH PASSAGE ACCOMMODATING AT LEAST ONE PRODUCTION STRING, AND UPWARDLY FACING SHOULDER MEANS DISPOSED AT THE UPPER END OF SAID BODY MEANS; A CHRISTMAS TREE ASSEMBLY COMPRISING A BASE MEMBER SEATED ON SAID UPWARDLY FACING SHOULDER MEANS AND HAVING A VERTICAL THROUGH PASSAGE, FLOW PASSAGE MEANS PLACED IN COMMUNICATION WITH SAID PRODUCTION STRING WHEN SAID BASE MEMBER IS SEATED ON SAID UPWARDLY FACING SHOULDER MEANS, A PLURALITY OF VERTICAL UPPER FLOW DEVICES SECURED TO SAID BASE MEMBER OUTWARDLY OF SAID THROUGH PASSAGE THEREIN, AND PRODUCTION CONDUIT MEANS INTERCONNECTING SAID PRODUCTION STRING AND ONE OF SAID UPPER FLOW DEVICES VIA SAID FLOW PASSAGE MEANS;