Patent Application
20050151099
1. Field of the Invention
This invention relates to a pressure compensated shear seal solenoid valve used in subsea hydraulic control systems for operating valves, blowout preventers and hydraulically actuated wellhead connectors. Such devices require pressurized hydraulic fluid, typically operated at 1500 or 3000 psi, for their operation. The solenoid valve of the present invention is used in the control of the flow of such pressurized hydraulic fluid.
These subsea hydraulic control systems typically consist of a group of accumulator bottles in which the pressurized hydraulic control fluid is stored, a control unit for operating the aforementioned solenoid valves, and high pressure lines or hoses to carry the hydraulic control fluid from the accumulator bottles to the control unit and its solenoid valves and thence to the function, such as open or close, of the designated valve, blowout preventer or wellhead connector. The pressurized hydraulic control fluid is stored in the accumulator bottles at the desired operating pressure of 1500 or 3000 psi.
Previous designs in the industry have suffered from such deficiencies as inadequate flow rates, unreliable operation, difficulty to service or repair and being too large which causes difficulties in fitting the required number of valves in the allowable space. It is therefore desirable to have a solenoid valve that offers improved flow rates over existing designs, ease of serviceability and reduced size for ease in designing hydraulic control systems. The pressure compensated shear seal solenoid valve of the present invention offers a substantial improvement by offering a solenoid valve that yields a substantially improved flow rate, ease of serviceability and reduced size.
2. Description of Related Art
U.S. Pat. No. 4,337,829 to V. Banzoli et al. shows a control system for subsea wellheads that comprises an electronic command and control unit, a valve actuating hydraulic electric unit, a power generator unit and interconnection devices for interconnecting the hydraulic lines for controlling the system from the surface.
A subsea control module is disclosed in U.S. Pat. No. 6,161,618 to W. C. Parks et al. The subsea control module consists of a lower portion with plate for carrying hydraulic couplings and hydraulic passages from valves to couplings, a one atmosphere dry nitrogen purged chamber in a pressure vessel dome contains electronics, wiring and solenoid valves and a mandrel for extending below for engagement with a central locking mechanism in a receiver baseplate.
U.S. Pat. No.6,318,408 B1 to Y. Fukano et al. shows a directional control valve.
A method and apparatus hydraulic and electro-hydraulic control of subsea blowout preventer systems is disclosed in U.S. Pat. No. 6,484,806 B2 to M. Childers et al.
The pressure compensated shear seal solenoid valve of the present invention is designed for use in subsea hydraulic control systems for operating valves, blowout preventers and hydraulically actuated wellhead connectors. The pressure compensated shear seal solenoid valve includes a hydraulic section with a flow control member or piston for controlling fluid flow through the solenoid valve and a coil section that operates the piston. A manifold is positioned between the coil section and the hydraulic section with the coil section and the hydraulic section secured to the manifold.
The hydraulic section includes a valve body with fluid supply and outlet ports on an end face. An inlet flange and an outlet flange are secured to the valve body on opposite sides. Internal porting allows fluid communication between the inlet and outlet flanges and in turn with the fluid supply and outlet ports. A piston is positioned within the valve body and has a central bore therethrough. The piston is moveable between open and closed positions to control fluid communication between fluid supply and outlet ports. A supply seal plate and an outlet seal plate are positioned on opposite sides of the piston, with the outlet seal plate having an arcuate shaped fluid passageway to maximize flow rate while requiring a minimum amount of piston travel between its open and closed positions.
The coil section comprises a coil cover having a substantially cylindrical shape with a mounting flange disposed on one end with a solenoid section disposed within the coil cover. The solenoid section including an electrically operated coil, a fixed metal core and a moveable metal core axially positioned a predetermined axial distance from the fixed metal core. An end cap is arrayed on the coil cover on the opposite end from the mounting flange. A bore extends axially through the fixed metal core with a plunger positioned within the bore and extending from the bore a predetermined distance at either end. The plunger is impacted and moved by the moveable metal core when the electrically operated coil is energized and thereby moves the piston. A flux ring encircles a portion of the moveable core and is sealed thereto. A pair of electrical leads supply power to the electrically operated coil.
A principal object of the present invention is to provide a pressure compensated shear seal solenoid valve with an improved flow rate.
Another object of the present invention is to provide a pressure compensated shear seal solenoid valve that minimizes the piston travel required to open and close the valve.
A final object of the present invention is to provide a pressure compensated shear seal solenoid valve that allows the use of a smaller coil for its operation
These with other objects and advantages of the present invention are pointed out with specificness in the claims annexed hereto and form a part of this disclosure. A full and complete understanding of the invention may be had by reference to the accompanying drawings and description of the preferred embodiments.
These and other objects and advantages of the present invention are set forth below and further made clear by reference to the drawings, wherein:
With reference to the drawings, and particularly to
Pressure compensated shear seal solenoid valve 10 is shown in sectional view in
Manifold 16 includes internal passages 32 which connect to fluid supply and fluid outlet connections 34 and 36, respectively. Passages 32 connect to fluid supply and outlet ports 38 and 40 in hydraulic section 12. Passages 32 are sealed to fluid supply and outlet ports 38 and 40 by seal subs 42. Manifold 16 also includes plunger bore 44 centrally located therein for purposes to be explained hereinafter.
The details of construction of hydraulic section 12 are best seen in
Valve body 46 includes central chamber 60 in which piston 62 is disposed. Piston 62 includes piston neck 64 extending from valve body 46. Seal ring 66 is positioned on the exterior of valve body 46 and seals valve body 46 to manifold 16 when assembled. The opposite side of valve body 46 has end cap 68 secured thereto by bolts 70 and sealed by seal rings such as O rings 72 and 73. End cap 68 has recess 74 formed on its interior surface with piston spring 76 positioned therein. Piston 62 has central bore 78 therethrough, perpendicular to the axis of travel of piston 62. Shear seal rings 80 are disposed within central bore 78 with urging means in the form of coil spring 82 positioned therebetween to urge shear seal rings 80 outwardly toward supply and outlet seal plates 84 and 86, respectively. Shear seal rings 80 include central bore 88 therethrough with tapered inner diameters 90 formed at their outer ends. Central bore 78 of piston 62 includes seal grooves 92 formed therein with O rings 94 disposed in seal grooves 92 and sealing the exterior of shear seal rings 80.
Referring to
As shown in
Referring to
The details of construction of coil section 14 are best seen in
Bore 140 extends axially through fixed metal core 132 and has plunger 142 positioned within bore 140. Plunger 142 extends from bore 140 a predetermined distance at either end and plunger 142 is impacted and moved by moveable metal core 134 when electrically operated coil 130 is energized. Flux ring 144 encircles a portion of moveable core 134 and is sealed thereto by a plurality of seal rings 146. Paired electrical leads 148 supply power to electrically operated coil 130. Electrical leads 148 extend through pressure transfer cap 138 and are sealed by pressure transfer cap 138. The interior of coil section 14 is filled with a predetermined amount of dielectric fluid 150 which displaces any air within coil section 14 and prevents ingress of foreign matter into coil section 14. Fill ports 152 provide a means for filling coil section 14 with dielectric fluid 150. Fixed metal core 132 and moveable metal core 134 have complimentary tapered faces 154 and 156 on their mating faces. Securing means in the form of snap ring 158 secures solenoid section 128 within coil cover 124.
A typical sequence of operation for pressure compensated shear seal solenoid valve 10 is as follows. Pressurized hydraulic fluid is supplied from a manifold of accumulator bottles, well known to those of ordinary skill in the art, to fluid supply connection 34 in manifold 16. The pressurized hydraulic fluid then flows through internal passage 32, through seal subs 42 to inlet flange fluid port 54 and to supply seal plate 84. The pressurized hydraulic fluid is then directed through shear seal rings 80 where the flow is stopped by outlet seal plate 86, if coil 130 is deenergized, as shown in
In a typical installation of pressure compensated shear seal solenoid valve 10, it is often desired to install a plurality of valves 10 in an integrated unit commonly referred to as a multi-function manifold. Such a manifold allows for the functioning of multiple subsea devices such as valves, blowout preventers and hydraulically actuated wellhead connectors. Construction details of such a typical unit using a plurality of pressure compensated shear seal solenoid valves 10 are shown in
The construction of our pressure compensated shear seal solenoid valve will be readily understood from the foregoing description and it will be seen that we have provided a pressure compensated shear seal solenoid valve that offers an improved flow rate and ease of serviceability. Furthermore, while the invention has been shown and described with respect to certain preferred embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalent alterations and modifications, and is limited only by the scope of the appended claims.
