US3509910A

US3509910A - Submergible wellhead valve and control system

Info

Publication number: US3509910A
Application number: US768018A
Authority: US
Inventors: Norman A Nelson; Jerry B Tomlin
Original assignee: ACF Industries Inc
Current assignee: ACF Industries Inc; Cooper Industries LLC
Priority date: 1968-10-16
Filing date: 1968-10-16
Publication date: 1970-05-05
Anticipated expiration: 1987-05-05
Also published as: AT296918B; ES371596A1; NL6915593A; GB1274692A; DE1950776A1; BR6913163D0; FR2020796A1

Description

y 1970 N. A. NELSON ET AL 3,509,910

SUBMERGIBLE WELLHEAD VALVE AND CONTRQL SYSTEM Filed Oct. 16, 1968 3 Sheets-Sheet 1 I N VE N TORS.

NORMAN A.NELSON 18 JERRY B. TOMLIYN B v ,a ATTOR May 5, 1970 3,509,910

SUBMERGIBLE WELLHEAD VALVE AND CONTROL SYSTEM N. A. NELSON ETAL.

Sheets-Sheet 2 Filed Oct. 16, 1968 m we INVENTORS.

NORMAN A.NELSON JERRY B- TOMLIN 'yrm' ATTORNEY v o: w: ww N: 3" N u LI? 2 i m l NM May 5, 1970 N. A. NELSON- ET AL 1 SUBMERGIBLE WELLHEAD VALVE AND CONTROL SYSTEM Filed 061;. 16, 1968 3 Sheets-Sheet 5 14 sf 1 A 7 I N VE N TORS. NORMAN A. NELSON JERRY B. TOMLIN I B FIG. 4 A T TORNE Y United States Patent 3,509,910 SUBMERGIBLE WELLHEAD VALVE AND CONTROL SYSTEM Norman A. Nelson and Jerry B. Tomlin, Houston, Tex.,

assignors to ACF Industries, Incorporated, New York,

N.Y., a corporation of New Jersey Filed Oct. 16, 1968, Ser. No. 768,018 Int. Cl. F16k 31/42 US. Cl. 137594 15 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION The petroleum industry, in its search for petroleum reserves, has developed and is continuing to develop procedures for drilling wells in the ocean floor and is capable of completing drilled producing wells in the hostile subsea environment. The petroleum industry is now capable of drilling in water depths which are far in excess of economical platform construction and at costs that make systems for subsea completion economically feasible. To assure complete exploitation of deep water petroleum reserves techniques are being developed to permit the drilling, producing and servicing of wells having completion equipment located at or adjacent to the ocean floor.

Submerged wellhead assemblies adapted for hydraulic control may be actuated through control conduits which extend to platforms located above the surface of the ocean or a hydraulic power source may be located on or adjacent to the wellhead assembly to provide operating fluid under pressure for control of the wellhead valves. Platform control of the submerged power operated equipment is generally preferred when platform completion is commercially feasible. When completion on the ocean floor is mandatory, however, it is generally necessary to provide a self-contained power supply system at or adjacent to the submerged valve. For submerged completions generally the power supply system is connected to the wellhead and a plurality of conduits extend from the power supply to the various valves which are to be operated. It has been found, however, that self-contained systems of this nature are expensive to install and replace and are extremely disadvantageous when servicing is involved.

Submerged wellhead systems utilizing self-contained power-pack actuation may also be subject to inadvertent actuation of the wellhead by the control system when the same is being serviced. It is obvious that inadvertent actuation of the wellhead during a servicing procedure could result in the development of a dangerous condition and could possibly result in complete loss of the well. Hydraulic fluid power supply equipment which is attached to a subsea wellhead system, generally requires special guidance systems so that the power supply system may be accurately positioned with respect to the wellhead during installation of the power supply system. Special guidance systems of this sort are extremely expensive in nature and contribute greatly to expensive servicing requirements of the system.

It is, therefore, a primary object of the present invention to provide an improved subsea Wellhead assembly which includes a self contained hydraulic fluid power supply system which is capable of being electrically or electronically controlled from a remote location to achieve control of a plurality of valves of a subsea wellhead assembly.

It is a further object of this invention to provide a novel subsea wellhead valve and control system which includes a wellhead valve assembly having a self-contained hydraulic fluid power supply system which may be easily and simply installed or detached from the wellhead valve system by remote control.

It is an even further object of our invention to provide a novel subsea Wellhead valve and control system utilizing a self-contained hydraulic power supply system which may be readily detached from the wellhead assembly and transported by the wellhead guidance system to the surface of the ocean floor for inexpensive servicing when required.

Among the several objects of our invention is contemplated the provision of a novel subsea wellhead valve and control system which includes a self-contained hydraulic fluid power supply system which forms the upper portion of the wellhead valve assembly and is removable from the wellhead for ready access to the well fluid passages when the well is to be serviced.

It is an even further object of our invention to provide a novel subsea wellhead valve and control system utilizing a self-contained hydraulic fluid power system which may be installed or removed from the wellhead without any necessity for providing a special removable and installation guidance system.

Yet another object of the present invention is to provide a novel subsea wellhead valve and control system which is simple in nature, inexpensive in manufacture and reliable in use.

Briefly stated, the present invention concerns a wellhead valve assembly including a plurality of wellhead valves which are operated to control the flow of fluid through at least one and preferably a plurality of wellhead flow conduits. Each of the plurality of valves is provided with a hydraulically energized valve operator which is actuated by hydraulic fluid under pressure to achieve movement of the valve to a preselected open or closed position and which is responsive to selective control or loss of hydraulic power to move the internal valve elements to a second preselected open or closed position.

The wellhead valve system includes a self-contained hydraulic fluid power supply system which is connected to the upper extremity of the wellhead valve system by means of a quick release collet mechanism. The collet mechanism includes hydraulic fluid supply conduit structure for establishing fluid communication between hydraulic fluid distribution conduits which conduct pressurized hydraulic fluid to the various valve operators for control thereof. The hydraulic fluid power supply system includes a fluid supply reservoir, the upper portion of which is defined by a cylindrical housing and the lower portion of which is defined by the interior portion of the :ollet connector. An electrically energized fluid supply pump is disposed within the fluid supply reservoir with the suction thereof in fluid communication with the reservoir and the discharge portion thereof communicated to the various fluid supply conduits of the system through a number of solenoid actuated valves. The solenoid valves are actuated either by remotely controlled electric circuitry or by remotely supplied electronic signal to achieve selective opening of the various valves to achieve desired selective operation of the wellhead valves. The hydraulic fluid power supply source includes a pressure balancing system to balance the pressure of fluid within the fluid reservoir with the seawater or other external environment in which the system is submerged. The fluid power source also includes an accumulator which is pressurized by the fluid pump and which cooperates with the fluid pump upon opening of a solenoid valve to achieve rapid movement of the valve operators.

The novel features of the present invention are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation together with other and further objects and advantage thereof, may best be understood by way of illustration and example when taken in conjunction with the accompanying drawings in which:

FIG. 1 is a parital elevational view of the Wellhead assembly of this invention having portions thereof broken away and illustrated in section.

FIG. 2 is a sectional view illustrating a valve and valve operator assembly of the wellhead in detail.

FIG. 3 is a fragmentary sectional view of the valve and operator assembly of FIG. 2 illustrating the modular hydraulic fluid connection structure thereof in detail.

FIG. 4 is a fragmentary sectional view of the valve and valve operator assembly of FIG. 1 illustrating the connection structure between the wellhead valve body and the hydraulic fluid power source.

Referring now to the drawings for a more detailed description of this invention, in FIG. 1 there is shown a wellhead valve body assembly for a dual completion wellhead having three

flow passages

12, 14 and 16 (FIG. I2) extending to two producing zones beneath the surface of the earth. One of the flow passages serves as a fluid return line to allow the circulation of fluids, oil tools, and other devices when the same are forced into and out of the well by fluid pressure. The valve assembly 10 includes a conduit for each of the strings of tubing, each conduitbeing controlled by a series of wellhead valves. One of the wellhead valves 18 has a valve body 46 defining a valve chamber 22 in which is reciprocated a gate member 50. The gate member 50 is provided with a port 51 which is disposed for registry with the flow passage 14 for controlling the flow of fluid through the flow passage.

The valve operator portion of the assembly illustrated generally at- 52 is connected to the valve body 46 by means of segment clamps 54 which maintain connection flanges on the valve body 46 and an operator base 56 in sealed abutting relation. The valve operator is of the linear hydraulic type including a hydraulic cylinder 58 in which is disposed a movable piston member 60. The piston member 60 is connected by means of a valve stem 62 to the gate member 50 in such manner that reciprocation of the piston member 60 induces reciprocal movement of the gate member between its open and closed positions. A compression spring member 64 is interposed between the piston 60 and the valve operator .base 56 and serves to bias the piston member outwardly away from the valve body.

To provide for energization of the hydraulic valve operator, the valve and operator assembly is provided with a hydraulic fluid supply passage system 66 which includes a fluid passage 68 in the valve body and a fluid passage 70 formed in the operator base 56. The

passages

68 and 70 are maintained in fluid communication through a connector tube 72 which establishes a sealed bridge between the valve body and operator base when the same are disposed in assembly. Hydraulic fluid from the passage 70 is communicated into a fluid passage defined by a tubular conduit member 74 which connects the operator base passage with a fluid passage 76 formed in the end cap 78 of the hydraulic operator. For energization of the hydraulic operator 54, hydraulic fluid from a hydraulic fluid power source is conducted through the valve and operator passage structure and is introduced into the cylinder 58 outwardly of the piston 60. Introduction of hydraulic fluid into the cylinder 58 outwardly of the piston 60 will cause the piston to move inwardly toward the valve body 46 thereby compressing the spring 64 and causing the valve stem 62 and the gate element 50 to be moved to a position aligning the port 51 in the gate with the production flow passage 14 of the wellhead. assembly. To close the valve, it is necessary that the hydraulic fluid supply system be controlled in such manner as to allow hydraulic fluid to flow freely out of the cylinder 58 and through the hydraulic fluid system 66. When this occurs, the combined eifect of the compression spring 64 and fluid pressure acting through the area defined by the stem 62 causes the stem and piston structure to be positively urged outwardly away from the valve body thereby moving the gate member 50 to its closed position and blocking the flow of fluid through the fluid passage 14 of the wellhead assembly.

For the purpose of supplying hydraulic fluid under pressure into the hydraulic system 66 of the operator and valve combination, one of several fluid supply module devices 82 is connected to the valve body 46 by means of a bolt device 80 shown in FIG. 2 and illustrated in detail in FIG. 3.

Referring now to FIG. 3, the fluid module 82 of the hydraulic fluid supply system is provided with a transverse connection passage having an internal enlargement 104 defined therein which cooperates with the cylindrical outer surface of the bolt 80 to define an annular chamber 105 surrounding the bolt. Sealing means 106 are provided to establish sealing engagement between the bolt member and the module 82 on each side of the annular enlargement 104 to serve the dual purpose of confining the hydraulic fluid to the annular chamber and preventing contamination of the hydraulic fluid by the external environment. The sealing means 106 may comprise resilient O-ring members such as shown in FIG. 3 or may comprise any other conventional sealing means without departing from the spirit or scope of the instant invention. The bolt member 80 is provided with a fluid passage 108 which establishes fluid communication between the annular chamber 105 and the fluid passage 68 of the hydraulic system 66.

For physical connection of the bolt 80 to the valve body 46, external threads 110 are provided on the bolt 80 and are received by an internally threaded portion 112 of a connection aperture 114. Sealing means 116 which may be an -O-ring type sealing member or any other suitable sealing means, are carried by the bolt 80 to provide sealing engagement between the bolt member and a cylindrical internal surface 118 defining the outer portion of the connection aperture 114. The sealing members 116 prevent leakage of hydraulic fluid from the hydraulic fluid system in the valve body 46 and also prevents the introduction of corrosive fluid from an external environment such as seawater.

Referring now to FIG. 4, a collet connector mechanism illustrated generally at 120 is provided for physically connecting a self-contained hydraulic fluid power supply source to the uppermost portion of the wellhead valve assembly 10. The collet connector 120 is provided with a connection flange 122 which is adapted for intimate sealing engagement with a connection flange 124 formed at the upper portion of the valve body. A plurality of blind sealing members, one for each of the flow passages, are carried by a body portion 130 of the collet connector 120 and are received within enlarged portions of the

flow passages

12, 14, and 16 and establish positive sealing engagement to prevent leakage of fluid from the flow passages when the collet connector structure is assembled to the valve body 10. Two of the

blind sealing members

126 and 128 are illustrated in FIG. 4. A plurality of movable segment clamps 132 are loosely carried by the collet connector 120 and in the assembled condition of the collet connector as illustrated in FIG. 4 function to bias the

flanges

122 and 124 into intimate sealing engagement. A frusto-conical surface 134 is formed on the interior of a collet shroud 136 and serves to force the segment clamps 132 into latching engagement with the

flanges

122 and 124 thereby latching the segment clamps in the position illustrated in FIG. 4. A release cam surface 138 is formed within the shroud 136 and is disposed for engagement with tail portions 140 of the segment clamps 132. As the shroud member 136 is moved upwardly as viewed in FIG. 4, the release cam surface 138 will engage the tail portions 140 and the segment clamps 132 causing the segment clamps to pivot in such manner as to release the

flanges

122 and 124. It is seen, therefore, that movement of the shroud member 136 downwardly will cause locking of the collet connector structure 120 to'the uppermost portion of the wellhead assembly 10, and that reciprocation of the collet connector shroud 136 upwardly will effect release of the collet connector from the wellhead valve assembly 10.

The shroud member 136 is provided with an internal shoulder 142 which cooperates with a large diameter cylindrical sealing surface 144 and a smaller diameter sealing surface 146 formed on the collet body 130- to define upper and lower

hydraulic actuation chambers

148 and 150 respectively. An annular closing member 152 is fixed to the collet body 130 by a clamp member 154 and a series of bolts 156.

Pressurized hydraulic fluid is communicated to the

hydraulic actuation chambers

148 and 150 through hydraulic

fluid supply conduits

158 and 160 which are formed within the collet body 130. Hydraulic fluid under pressure, forced into the upper hydraulic actuation chamber 148 through the conduit 158, will act against the shoulder 142 of the shroud 136 and will force the shroud downwardly with respect to the collet body 130. Downward movement of the shroud relative to the collet body cause clamping and locking of the segment clamps 132 to the

annular flanges

122 and 124 in the manner discussed above. Introduction of pressurized hydraulic fluid into the lower hydraulic actuation chamber 150 through the conduit 160 will develop a force against the lower surface of the shoulder 142 which causes movement of the shroud 136 upwardly relative to the collet body as shown in FIG. 4 thereby causing release of the segment clamps 132 from the

flanges

122 and 124 as discussed above.

The interior walls of the collet body 130 define the lower portion of a hydraulic fluid reservoir 162 which serves as a reservoir for hydraulic fluid. A connector plate 164 is fixed to the upper portion of a collet body 130 by means of bolts 166 and is provided with av peripheral flange 168 which is retained in intimate sealed engagement with the lower flange 170 of a cylindrical housing 172 by a clamp member 171. A closure member 174 is connected to the housing 172 by means of a clamp member 176 and is provided at its upper extremity with a bell-mouth guide portion 178 which serves as a guide for installation and retrieval tools which are lowered into engagement therewith. A connector pin 180 is fixed centrally of a circular wall 182 which forms the closure plate of the closure member 174. Installation and retrieval tools will receive the pin member for the purpose of raising or lowering the self-contained hydraulic fluid supply system to or from the wellhead. It should be noted that since the pin 180 is disposed On the vertical centerline of the wellhead valve body 10 the same guidance system for lowering and raising the wellhead may be employed to raise and lower the hydraulic fluid supply system.

The cylindrical housing 172 is provided with a series of perforations 184 which allow seawater or any other environment in which the wellhead valve system is submerged to pass therethrough. The upper portion of the reservoir 162 is separated from the seawater by a flexible membrane 186 which is capable of expanding and contracting due to volumetric changes within the fluid reservoir 162. The flexible membrane 186 and the apertures 184 assure that the internal pressure of the fluid within the reservoir 162 will always be balanced with the hydrostatic head of the seawater in which the system is submerged.

A fluid pump 188 is connected by brackets 190 to the upper portion of the connector plate 164 and is energized by means of an electric motor 192. The suction of the pump 188 is disposed in fluid communication with the interior of the reservoir 162. The pump 188 is provided with a discharge conduit 194 which comprises a manifold to which is connected a series of hydraulic fluid supply conduits 196 including solenoid actuated valves 198 for controlling the flow of fluid therethrough. For the purpose of simplicity, only one conduit and solenoid valve is illustrated in FIG. 1 of the drawings, but it is to be understood that a number of solenoid valves will be disposed in fluid communication with the discharge manifold 194 of the pump 188. A plurality of fluid conduits 200 are formed in the connector body 130 and are disposed in registry with a plurality of corresponding hydraulic fluid distribution conduits 202 formed in the upper extremity of the wellhead valve body 10. The conduits 202 are disposed in fluid communication with the plurality of conduits 204 one extremity of each of the conduits being threadedly received within the outer threaded extremities of the fluid passages 202.

The conduits 204 are communicated with a fluid supply input module 206 which forms the upper extremity of a fluid distribution system. A plurality of fluid transfer conduits 208 depend from the input module 206 and transfer hydraulic fluid under pressure to various distribution modules, one of which is illustrated at 82 in FIG. 1. Pressurized hydraulic fluid from the fluid supply system upon reaching the modules 82 will be transmitted into the various valve and hydraulic actuator assemblies for selective control thereof.

The solenoid valves 198 may be actuated either by electrical circuitry 199 which extends from a remotely located control facility to the wellhead assembly or by electric current controlled by remotely transmitted signals from the control facility. The control facility may be located on the shore or it may be situated on a floating or rigid control platform at the surface of the ocean. The valves of a subsea wellhead may be controlled by means of electric power which is supplied by a battery 210 connected to the upper extremity of the wellhead. The storage battery 210 may be continuously recharged by a trickle current transmitted from a remotely located source of electrical energy. A protective cover 212, encloses the curved conduits 204 and serves to .protect the conduits from external damage. The protective cover 212 is connected to the wellhead by means of bolts 214 which are received within the input module 206 or which extend through the input module 206 and are received within bosses 215 formed on the wellhead body.

For electronic actuation of a solenoid valve 198, signal receiving apparatus 216 is fixed to the hydraulic fluid supply source. The signal receiving apparatus 216 may be equipped to receive sonar signals, electronic-impulse signals or electrical signals from remote sources and through logic circuitry,.with which the signal receiving apparatus is equipped, transmits electrical signals for energization of a selected one or more solenoid valves'198 thereby causing hydraulic fluid under pressure to be transmitted to a selected one of the valve operators for operation of the same as discussed above. If desired, the signal receiving apparatus may be disposed within the fluid reservoir to protect it from external damage.

For the purpose of assisting the hydraulic fluid pump 188 in supplying pressurized hydraulic fluid an accumulator 220 is connected to the hydraulic fluid supply system by a conduit 221 which is disposed in fluid communication with the discharge manifold 194 of the pump 188. A compressible fluid such as air or dry nitrogen is disposed within the accumulator 220 and is compressed by hydraulic fluid forced therein by the hydraulic pump 188. The electric motor 192 will be deenergized by pressure responsive electrical circuitry when fluid pressure within the accumulator reaches a predetermined maximum value such as 1800 p.s.i., for example. Upon actuation of any one or more of the solenoid valves 198, the motor 192 will be energized and the pump 188 will begin to pump fluid through the discharge manifold 194. Simultaneously, pressure within the accumulator 220 is conducted through the solenoid valves 198 through the passages 200 and to the hydraulic distribution system of selected valve and operator assemblies to assist the pump in operation of the selected wellhead valves. The accumulator likewise may be disposed within the housing defining the fluid reservoir 162.

The wellhead valve and valve operator assembly may be installed with the hydraulic power supply system in attachment therewith or may be installed with the power supply system detached and with the

flow passages

12, 14, and 16 in an open position as desired. The hydraulic fluid power supply system may be lowered into engagement with the uppermost portion of the wellhead valve body 10 utilizing the same guidance system for lowering as is utilized for lowering the wellhead valve and operator assembly. As the hydraulic fluid power supply system is lowered, the shroud 136 of the collet connector structure will be located in its upper position and the clamp members 132 will be pivoted upwardly to the unlatched position thereof as indicated above. After the

flanges

122 and 124 have been placed in abutment, fluid pressure is introduced through the hydraulic passage 158 into the upper hydraulic actuation chamber 148 forcing the shroud member 136 downwardly with respect to the collet body 130 and causing the clamp members 132 to be pivoted into locking engagement as illustrated in FIG. 4.

For actuation of any one of the wellhead valve operators, an appropriate signal is transmitted from a remotely located signal transmitting source to the signal receiving apparatus 216. This signal will be transmitted by logic circuitry of the signal receiving apparatus into a signal energizing one or more of the solenoid valves 198. The solenoid valves upon being selectively actuated will open allowing hydraulic fluid under pressure to be transmitted from the manifold 19 4 and from the hydraulic fluid accumulator 220 through the conduit 196 and

fluid passage

200 and 204 and to the appropriate one of the hydraulic operators through the fluid distribution conduits 208. Subsequent to actuation of a selected one of a valve operator assemblies, the pump 188 will continue to be driven by the electric motor 192 sufficiently to increase pressure within the accumulator 220 to a predetermined maximum pressure at which pressure the pump 188 will be stopped by deenergizing the motor 192.

The hydraulic fluid supply source is readily removed from the wellhead body 10 simply by introducing hydraulic fluid under pressure into the lower hydraulic actuating chamber 150 causing the shroud 136 to be forced upwardly with respect to the collet body 130. This movement causes the cam surfaces 138 of the shroud to engage the tail portions of the clamp members 132 pivoting the clamp members to the open or unlatched position thereof and effectively releasing the

flanges

122 and 124. Suitable lifting apparatus which receives the lifting pin member may then lift the hydraulic fluid power source from the Wellhead body and transport the same to the surface of the ocean for servicing orfor storage until subsequently needed. The blind closure members such as those shown at 126 and 128 in FIG. 4 being connected to the collet body 130 will be removed along with the hydraulic fluid power source thereby leaving the

fluid passages

12, 14, and 16 open for servicing. It is readily apparent that installation and removal of the hydraulic power source from the wellhead body can be accomplished without any necessity of making or breaking external hydraulic conduit connections. Moreover, it is clearly apparent that servicing of the wellhead valve body may take place without any possible danger of inadvertently actuating a valve and valve operator in such manner as to cause movement of a valve to an unsafe condition.

It will be evident from the foregoing that we have provided a unique subsea wellhead assembly, which includes a self-contained hydraulic fluid supply system which is capable of being electrically or electronically controlled from a remote location to achieve control of a plurality of wellhead valves in a subsea wellhead system. The hydraulic fluid power supply system of my invention is connected at the upper extremity of the wellhead valve body in such manner as to form a closure for a plurality of fluid passages formed within the wellhead valve body so that the power supply source effectively forms the upper extremity of the wellhead. The hydraulic fluid sup ply system is connected to the valve body through utilization of a simple and efficient collet connection structure which clamps the fluid supply system to the wellhead body or disengages the fluid supply system from the well body responsive to linear actuation of a collet shroud member. The self-contained hydraulic fluid supply system can be installed and removed in response to remote selective remote control and may be actuated in response to remote control for selectively opening or closing any one of a plurality of wellhead valves of the wellhead valve assembly.

It is important to note that servicing of the wellhead Valve assembly may take place with the self-contained hydraulic fluid supply system removed from the wellhead thereby obviating any possibility of inadvertently actuating one or more of the wellhead valves creating a dangerous condition. Through utilization of the novel selfcontained hydraulic fluid power supply source of our invention, assembly, and disassembly of external connection structures for hydraulic fluid supply and distribution between the fluid system and the wellhead body is completely eliminated. Since the hydraulic fluid power system of our invention is installed at the upper portion of the wellhead valve, it is quite obvious that the same guidance system may be used for installation of the fluid power system ash is utilized for installing the wellhead valve body.

Therefore, is it clearly evident that our invention is one well adapted to attain all of the objects hereinabove set forth together with other advantages which will become obvious and inherent from a description of the apparatus itself. It will be understood that certain combinations and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the appended claims.

As many possible embodiments may be made of the invention without departing from the spirit or scope thereof, it is to be understood that all matters hereinabove set forth or shown in the accompanying drawings are to be interpretative as illustrative and not in a limiting sense.

We claim:

1. A submergible wellhead valve assembly comprising a wellhead valve body having a fluid flow passage means theretbrough and having a valve means for controlling the flow of fluid through said flow passage means, said valve means having hydraulically energized valve operator means for controlling opening and closing of said valve means, a self-contained electrically energized hydraulic fluid power source defining the upper extremity of said wellhead valve assembly, said fluid power source having remotely controlled connection means for releasably securing the same to the upper extremity of said wellhead valve body, said connection means establishing fluid communication between said fluid power source and said valve operator means whereby said valve operator means may be selectively energized for controlling movement of the wellhead valve means in response to selective energization of said fluid power source.

2. A submergible wellhead valve assembly as set forth in claim 1, said fluid power source having a collet connector at the lower extremity said collet connector being actuated to releasably secure said fluid power source to said wellhead valve body.

3. A submergible wellhead valve assembly as set forth in claim 2, said collet connector being hydraulically energized to secure said fluid power source to said wellhead valve body and to release said fluid power source from said wellhead valve body.

4. A submergible wellhead valve assembly as set forth in claim 2, said collet connector having closure means thereon forming sealed closures for said fluid flow passage means.

5. A submergible wellhead valve assembly as set forth in claim 2, hydraulic fluid distribution passage means formed in said valve body and being in fluid communication with said valve operator means, hydraulic fluid supply means formed in said collet connector means and establishing sealed fluid communication with said hydraulic fluid distribution means, said power source having control means for selective energization of said valve operator means through said fluid supply and fluid distribution passage means.

6. A submergible wellhead valve assembly comprising a wellhead valve body having a plurality of fluid flow passages formed therein, said valve body having at least one valve for each of said fluid flow passages, each of said valves having a hydraulically actuated valve operator for controlling opening and closing thereof to control the flow of fluid through said fluid flow passages, a self-contained electrically energized fluid power source defining the upper extremity of said wellhead valve assembly, said fluid power source comprising a housing defining a fluid reservoir, said reservoir being filled with hydraulic fluid, pump means disposed within said reservoir and having the suction opening thereof disposed in fluid communication with said reservoir, said pump having a discharge manifold and being capable of producing hydraulic fluid under pressure when energized, said power source having a plurality of hydraulic fluid supply conduits disposed in fluid communication with said discharge manifold, control valve means for selectively controlling the flow of hydraulic fluid through said hydraulic supply conduits, a plurality of fluid distribution conduits being in fluid communication with said valve operators and with said fluid supply conduits whereby selective actuation of one or more of said control valve means will produce actuation of a selected one of said valve operators, means releasably connecting said fluid power source to the upper extremity of said wellhead valve body.

7. A submergible wellhead valve assembly as set forth in claim 6, said means releasably connecting said fluid power source to said wellhead valve body defining a portion of said fluid reservoir.

8. A submergible wellhead valve assembly as set forth in claim 6, said fluid power source having pressure balancing means to insure a balanced pressure condition of the hydraulic fluid within said reservoir and the hydrostatic head of the environment in which said assembly is located.

9. A submergible wellhead assembly as set forth in claim 6, said means releasably connecting said fluid power source and said wellhead valve body comprising a plurality of segment clamps receiving the lower extremity of said fluid power source and the upper extremity of said wellhead valve body, cam means engaging said segment clamps and moving the same from an unlatched position thereof to a latched position where said segment clamps bind said fluid power source to said Wellhead valve body.

10. A submergible wellhead assembly as set forth in claim 6, said means releasably connecting said fluid power source and said wellhead valve body comprising a first flange formed on said fluid power source and a second flange formed on the wellhead valve body, a plurality of segment clamps carried by said fluid power source, a movable clamp actuation member carried by said fluid power source and being capable of moving said segment clamps between a latched position where said clamps bind said flanges into intimate sealed engagement and an unlocked position where said clamps release said flanges, whereby said fluid power source may be disconnected from said wellhead valve body upon selective movement of said clamp actuation member.

11. A submerged wellhead assembly as set forth in claim 10, closure means carried by said fluid power source and being received in sealed engagement within the flow passages of said wellhead valve body, said closure means being removed from said flow passages upon removal of said fluid power source from said wellhead valve body, thereby exposing said flow passages for servicing.

12. A self-contained hydraulic fluid power source for a submergible wellhead having a plurality of flow passages formed therein and having a plurality of hydraulically energized valves for controlling the flow of fluid through said flow passages, said Wellhead valve body having a connecting flange at the upper extremity there of and having a plurality of hydraulic fluid distribution conduits extending from said connecting flange to said hydraulically energized valves, said fluid power source comprising a collet body having a connecting flange formed at the lower extremity thereof, a plurality of segment clamps being movably disposed about said collet body, a shroud member disposed about said collet body and engaging said segment clamps and in the latched position thereof biasing said segment clamps into portion securing said connecting flanges into sealed assembly, means for selectively moving said shroud member, housing means connected to said collet body and c0- operating with said collet body to define a hydraulic fluid reservoir, hydraulic fluid disposed within said reservoir, pump means disposed within said reservoir and having a suction opening in fluid communication with said reservoir and a discharge conduit, a pluralty of fluid supply conduits extending from said discharge conduit to said fluid distribution conduits, valve means for each of said fluid supply conduits, said valve means being remotely and selectively actuatable for selective control of said hydraulically energized valves.

13. A self-contained hydraulic fluid power source as set forth in claim 12, said shroud member being hydraulically actuated from a remote control point.

14. A self-contained hydraulic fluid power source as set forth in claim 12, means maintaining the pressure as said hydraulic fluid within said reservoir in a balanced condition with the hydrostatic head of the medium in which said fluid power source is submerged.

1'2 15. A self-contained hydraulic fluid power source as References Cited set forth in claim 12, accumulator means disposed in V UNITED STATES PATENTS fluid communication with said pump discharge conduit,

2,614,803 10/1952 Wlggms 166--.5 XR a compressible flu1d disposed w1thm said accumulator 3,101,118 8/1963 Culver 166 '5 and being compressed by hydraulic fluid as the same, 5

whereby pressurized hydraulic fluid stored within said HAROLD WEAKLEY, Primary Examiner accumulator serves to assist the pump in providin hydraulic fluid for operation of said valves upon actuation of said fluid supply conduit valve means. 137 23'6, 79 25 ,30 14