US3545541A - Wellhead assembly including diverter means - Google Patents

Description

Un1ted States Patent 1111 ,5

[72] Inventor Douwe DeVrles [56] References Cited Mm, lmishm UNITED STATES PATENTS 1 PP 3,136,363 6/1964 Yetman e161. 166/9sx 1 PM 3,139,932 7/1964 Johnson l66/95X 1 9 3,307,631 3/1967 Coberly eta]. 166/.sx W CWPW k 3,414,056 12/1968 Brown 6130.. 166/.sx 3,454,084 7/1969 Sizer 166/.6 a corporation of Delaware Primary Examiner-Marvin A. Champlon Assistant Examiner-Richard E. Favreau [54] WELLHEAD ASSEMBLY INCLUDING DIVERTER Attorneys-J. H. McCarthy and Thomas R. Lampe MEANS 7 Claims, 5 Drawing Figs.

[52] U.S.C|. 166/95,

l66/.5 ABSTRACT: A wellhead assembly for use with oil or gas [51] Int. Cl EZlb 33/03. wells, said assembly including diverter means lectiv ly 1.

E21!) 33/035 tionable to (1) provide access to the well for through-the- [50] Field Of staid] 166/5, .6, flowline" operations or (2) permit vertical entry into the well 95 for maintenance or other operations.

40- J? A 39 3s 34 '1 4| 3 l 1 l I 54 so a 1 r 1 5| 55 428 se t ---37 29 PATENTEDDEE 819m '5 I $545,541

sum 1 or 3 INVENTOR:

D. de VRIES H IS ATTORNEY PATENTEDBEB emu 3545;541

SHEET 2 [IF 3 INVENTOR D. de VRI ES HIS ATTORNEY PATENTED DEC 81970 SHEET 3 OF 3 INVENTORI FIG. 5 0. deVRIES 1 ms ATTORNEY BYI/ WELLHEAD'ASSEMBLYNCLUDING DIVERTER MEANS This invention relates to equipment used at the top of an oil i or gas well and pertains moreparticularly to a wellhead assembly adapted to be secured to the top of a well casinghead and gas wells has been thedrilling and completion of un- I,

derwater. wells wherein both the wellhead assembly and casinghead may be positioned hundreds of feet below the surface of water at an offshorelocation. In order to carry out maintenance or other operationson wells wherein the wellhead assemblyis'positioned. a ,considerable'distance below the surface of the water, new methods have been developed. One of these methodshas been classified as a through-the-flowline well maintenance techniqueIWith this techniqueivarious well activities,xsuch as routine work-over and maintenance operations, are carried out-by tools which are pumped through a flowline from a remote location, such as an onshore storage facility, into the well bore 'After'the completion of the desired operation, such as the cleaning of paraffin from a tubing 1 string,,,the removal or insertion of a choke or valve, etc., the tool is pumped out of the well and back through the flowline to the remote location. i

While'simple well maintenance operations can be carried out by circulating tools through the flowline down into the well,'the more importantwork-over operations require thatthe underwater wellhead assembly be entered from the top with tools passing vertically downthroughthe assembly into thewell UQS. PaLNo. 3,101,118, issued Aug. 20, 1963, to. Culver et al. illustrates a form of wellhead assembly which will permit both vertical entry for-major maintenance work and side entry for through-the-flowline operations. The ,apparatus disclosed in that patent utilizes diverter means including diverting plugs and a plurality of valves to condition the assembly for. either vertical entry work or through-the-flowline work. Placement and/or removal of'the plugs as well as actuation of certainvalves mu'st'be accomplished through the --use of wire line or similar. tools, often a time-consuming matter. Then too, there is the possibility that the plugs or valves will be incorrectlypositioned or oriented in the wellhead assembly or even stuck therein, I

j SUMMARY oF'THE INVENTION It is therefore an object of the present invention to provide a wellhead assembly incorporating diverter means not requiring the use of wire lines or similar tools to effect the positioning thereof. I l o Another object of the present invention is to provide a wellhead assembly incorporating diverter means comprising valve means selectively movable between a first position wherein well bore through-the-flowl ine. v operations may be carried out and a second position wherein well bore vertical entry work may be performed. i I l i The above objects have been attained in the present invention by providing a wellhead assembly which includes both side conduit means which permit the passage of through-theflowline tools therethrough and additional conduit means which provide vertical access to the interior of the assembly 1 and well for maintenance and other operations. Both of the position, the-valve means establishes fluid communication between the side conduit means and tubing extending into the well, while in a second position the valve establishes fluid communication between the additional conduit means and the tubing. I

, 2 DESCRIPTION QF TI-IE DRAWING Other objects, purposes, and characteristic features of the present invention will be obvious from the accompanying drawings and from the following description of the invention. In describing the invention in detail, reference will be made to the accompanying drawings in which like reference characters designate correspondingparts throughout several views, and in which:

FIG. 1 is a diagrammatic view, taken in partial longitudinal cross section, of a wellheadassembly of the present invention seated on the top of well casinghead;

FIG. 2 is a' longitudinal view taken in cross section of the diverter means employed in the wellhead assembly of FIG. 1;

FIG. 3-is a cross-sectional view taken along the line 3-3 of FIG. 2; FIG. 4 is a plan view taken inpartial cross section of an alternative form of diverter nieans;and 1 FIG. 5 is a partial cross-sectional view taken along the line S-SofFlGA.

While thejwellhead assembly of the present invention is described hereinbelow with regard .to a well having two strings of production tubing suspended therein, itwill be readily apparent that the present wellhead assembly can be modified so as to be employed on wells having a single string of tubing therein or wells having three or more parallel strings of tubing suspended within a well casing. 1

Referring to FIG. 1 of the drawing, a casinghead closure member 11 isshown as positionedon the inner sloping seating surface 12 at the top of a casinghead 13, thus closing the casinghead 13 in a fluid-tight; manner. Seal means (not shown) may be provided between the casinghead closure member 1 and the casinghead 13 to. insure the fluid-tight fit therebetween. The casinghead closure member 11 is provided with a pair of vertical conduits 14'and 15 centrally disposed in side-by-side arrangement "and extending vertically down through thecasingheadclosure member in register with a pair of strings ofproduction tubing (not shown) suspended within the well in the usual manner. For purposes of illustration it may be assumed that the well casinghead l3 and the wellhead assembly of the present invention are mounted on an olfshore well and are positioned under water.

Fixedly secured to the top of the casinghead closure member 111 by any suitable expedient such as bolts (not shown) is a master valvel6by which the well may be shut in upon closingof the valve 16. The valve 16 is preferably of the remotely-controlled full opening type, that is, the gate or plug controlling flow within the valve is of a type that, when open, furnishesa straight passageway through the valve of a diameter substantially equal to'that of the vertical conduits 14 and At their respective uppermost ends, vertical conduits 22 and 23 of the Y spool piece 21 communicate with cylindrical housing members 24 and 25 also formed in Y spoolpiece 21, which house diverter means comprising rotary valves 26 and 27 as showmf Smoothly curving upwardly from cylindrical housing members 24 and 25 are a pair of side conduits 28 and 29 which branch outwardlythrough the side wall of the spool piece 21. The curvature of the side conduits 28 and 29 depends, to'some extent, upon the length and flexibility of the tools, instruments, or other devices, to be circulated down into the well through the side conduits. Thus, with the presently developed tools, the radius of curvature of the side conduits 28 and 29 maybe on the order of 5 to 10 feet.

The side conduits 28 and 29 are provided with flanges 30 and 31, respectively, or other coupling means, for connecting control valves 32 and 33 to the side conduits 28 and 29,

respectively. A pair of production flowlines 34 and 35 are connected to the other side of the control valves 32 and 33. The flowlines 34 and 35 which lead to the top of the wellhead assembly eventually curve outwardly and downwardly to the ocean floor and then run along the ocean floor to shore or to some tank positioned offshore for collection or separation purposes. In the event that the sections of the production flowlines 34 and 35 are metal, they should be smoothly curved in an arc of a radius no less than that which would permit objects to be circulated therethrough into the well. It is quite apparent that whether the flowlines 34 and 35 are of a rigid or flexible material that all curves therein must have a minimum radius of not less than that required for circulation of objects therethrough.

Spool piece 21 is also provided with a pair of spaced vertical bores 36 and 37 which overlie and are in communication with cylindrical housing members 24 and 25 respectively. The vertical bores 36 and 37 are positioned in axial alinement with vertical conduits 14 and and are of substantially the same inner diameter as vertical conduits 14 and 15. Fixedly secured to the top of Y spool piece 21 is a control or swab valve 38 which is preferably of the identical design as the master valve 16, having dual passageways therethrough with full-opening plugs or gates therein. Control valve 38 has seated thereon and affixed thereto in any known manner a vertical reentry conduit 39 having vertical conduits 40 and 41 therein which are in register'through valve 38, with vertical bores 36 and 37. The vertical reentry conduit may be closed in a suitablefluid-tight manner, such, for example, as described in application Ser. No. 830,587, filed Jul. 30, 1959, or may be provided with a flexible joint whereby the major length of the reentry conduit can be folded over to rest on the ocean floor, as described in U.S. PatNo. 3,064,735, issued Nov. 20, 1962, to Bauer et al.

. The entire wellhead assembly of the present invention is preferably covered by a fluid-tight housing 42 to protect the known in the art, and since they do not form part of the trically driven pumps 58 and 59. The pressure fluid is con- I tained in reservoirs 60 and 61.

Referring now to FIGS. 2 and 3, it may be seen that rotary valves 26 and 27 are each provided with passage means comprising a pair of throughbores; valve 26 having a curved throughbore 62 and'a straight throughbore 63 while valve 27 incorporates a curved throughbore 64 and a straight throughbore 65. As stated above, rotary valves 26 and 27 are mounted for relative rotatable movement within spool piece 21. To this end, valve 26 includes a pair of axially spaced projections 66 and' 67 which are disposed within cooperating recesses 68 and 69 respectively of housing member 24. Likewise, valve 27 incorporates projections. 70 and 71 which cooperate with recesses 72 and 73 respectively of housing member 25. The projections and recesses are of such relative dimensions that valves 26 and 27 are allowed to rotate in s rotary fashion about a fixed axis. Seal means, such as O-ring seals, are preferably utilized to maintain a fluid-tight fit between the projections and the recesses.

Curved hollowed out portions 74 and 75 are provided in spool piece 21 to communicate with housing members 24 and 25 respectively as shown. Hydraulic actuator units 76 and 77 are mounted on spool piece 21 and include actuator arms 78 and 79 whichextend through cooperating passageways in the spool piece into hollowed out portions 74 and 75 respectively. Itshould be understood that hydraulic actuator units 76 and may be of any known type and that arms 78 and 79 are selectively movable from a retracted position (the position ilpresent invention, they will not be further described here.

Rotary valves 26 and 27 have formed therein indent portions 80 and 81 which lie in the same plane as the spool piece curved hollowed out portions 74 and 75. Pin members 82 and 83 are fixedly connected to rotary' valves 26 and 27 and are vertically disposed within indent portions 80 and 81 respectively. Actuator arms 78 and 79 branch out at their respective ends to form slotted U-shaped members 84 and 85 with the slots thereof surrounding pin members 82 and 83 thus creating a connection therebetween in an obvious manner.

The operation of the wellhead assembly according to the present invention will now be described. With regard to such description, for the purposes of simplicity, the operation of the diverter means will be described with particular reference to that half of the assembly in which rotary valve 26 is housed. As stated above, the disclosed assembly is of the general type used for producing two separate zones of oil or gas and it should be readily apparent that the operation of valve 26 associated with one zone is the same as that of valve 27 as sociated with the second zone. In other words, the desired operations can be carried out independently for each of the two zones. Returning briefly to FIG. 1, both rotary valves are shown in the position assumed thereby when either production fluid is flowing from the well to the storage facility (not shown) or through-the-flowline operations are to be carried out. Arms 78 and 79 (FIGS. 2 and 3) are in their extended position and valves 26 .and 27 are positioned so .that the curved throughbores 62 and 64 thereof provide communication respectively between side conduit 28 and vertical conduit 22 and side conduit 29 and vertical conduit 23. Assuming master valve 16 is in an open condition, production fluid will then be free to flow from both well tubing strings (not shown), through the wellhead assembly and thence through flowlines 34 and 35. Likewise, through-the-flowline tools, instruments, etc., may be pumped down intothe tubing strings from the flowlines. v

To permit vertical entry for major workover or maintenance operations actuator units 76 and 7 7 are energized to retract their arms to rotate the rotary valves. The thus rotated valves will then be in the position illustrated with respect to valve 26 in FIGS. 2 and 3. In this position, straight throughbore 63 of rotary valve 26 provides communication between vertical bore 36 and conduit 22 of the Y spool piece 21. Assuming control valve 28 is open,vertical entry access may then be had to the interior of the well and flowline 28is cut off from its associated string of tubing in the well. To ensure proper positioning of the rotary valves for the desired operations, they may be provided with integral projections 86 and 87 which cooperate with curved recesses 88 and 89, respectively, thehousing 94 and 95, respectiyely,.'as desired. Valve has passage means comprising throughbores 96 and 97 passing through the body thereof while valve 91 incorporates passage means comprising throughbores 98 and 99 of similar configuration. When valve 91 is in the position illustrated, fluid communication is provided through throughbore 99 between side conduit 29' and conduit 14' for through-the-ilowline operations. As with the form of divertergineans illustrated in FIGS.

1-3, seals are provided at strategic locations to ensure a liquid-tight seal between valves 90 and 91 and the surrounding housings in the Y spool piece. 1

While this invention has been described with particular reference to preferred embodiments thereof, it should be understood that the particular forms disclosed have been selected to facilitate explanation of the invention rather than to limit the number of forms which it may assume. Further, it should be understood that various modifications, alterations, and adaptations may be applied to the specific forms described to meet the requirements of practice without in any manner departing from the spirit of the invention or the scope of the subjoined claims.

I claim: t l

1. A wellhead assembly adapted to be secured to the top of a well casinghead for controlling the fluid flow from said well while providing dual conduit means selectively permitting the vertical entry of devices into the well as well as the circulation of devices into said well, said wellhead assembly comprising:

a casinghead closure connected to. said well casinghead and having vertical conduit means therethrough;

a spool piece having vertical conduit means therethrough in register with the vertical conduit means in said casinghead closure;

side conduit means branching upwardly and outwardly through the side wall of said spool piece;

valve housing means in said spool piece, said housing means being in communication with said side conduit means and said vertical conduit means;

vertical reentry conduit means. disposed above said spool piece; and

fluid diverter means including valve means having passage means and closure means therein, said valve means being disposed in said housing means, said valve means being laterally movable with respect to said side conduit means tion between said spool piece vertical conduit means and said vertical reentry conduit means when in said first position.

3. The wellhead assembly according to claim 2 wherein said valve means includes structure interrupting fluid communication between said spool piece vertical conduit means and said side conduit means when in said second position.

4. The wellhead assembly according to claim 1 wherein said passage means comprises a first throughbore and a second throughbore, said that throughbore being disposed between said spool piece vertical conduit means and said side conduit means when said valve means is in said first position and said second throughbore being disposed between said spool piece vertical conduit means and said vertical reentry conduit means when said valve means is in said second position.

5. The wellhead assemblyaccording to claim 4 wherein said I valve means is reciprocatably,'axially movable between said first position and said second position.

6. The wellhead assembly according'to claim 4 wherein said valve means comprises rotary valve means which is moved between said first position and said second position by a remotely controlled actuator unit.

7. The wellhead assembly according to claim 6 wherein said rotary valve means is provided with projection means cooperating with recess means in said spool piece to define the limits of movement of said rotary valve means.

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