Pressure-balanced valve for underwater chemical injection

Abstract

A slide valve (200) for controlling a flow connection from an inlet (154) to an outlet (158) with respect to a reference pressure, wherein the inlet (154) and the outlet (158) are defined in a receiving area (152) of a component (150), the slide valve comprising: a cartridge (260) configured for positioning in the receiving area (152) of the component (150) with the inlet (154) and the outlet (158), wherein the cartridge (260) is arranged in sealed communication with the inlet (154) and the outlet (158) and defines a passage (262) for communication with the inlet (154); an outlet channel (280) disposed in the passage (262) and connecting the passage (262) to the outlet (158); a piston (270) disposed in the passage (262) and movable therein between a first and a second position relative to the outlet channel (280), wherein the piston (270) is movable in a first direction from the first position to the second position in response to an inlet pressure level at the inlet (154); a slide (290) arranged on the piston (270) and biased transversely to the outlet channel (280), wherein the slide (290) moved by the piston (270) adjusts the flow from the passage (262) to the outlet channel (280); and a pressure compensating device (220) disposed opposite the piston (270) and biasing the piston (270) in a second opposite direction extending from the second position to the first position; wherein the pressure equalization device (220) comprises a housing (221) defining a chamber (222) in communication with the reference pressure, the housing (221) being configured for mounting in the receiving area (152) and for holding the cartridge (260) therein.

Description

BACKGROUND OF REVELATION 1. Area of ​​Revelation

[0001] The subject matter of the present disclosure relates to valves. More particularly, it relates to pressure-balanced valves for use in an underwater environment. 2. Description of related technology

[0002] US 4,456,028 A discloses a relief gate valve. However, this valve is not suitable for use in underwater environments. It requires manual adjustment to set the opening pressure and does not compensate for hydrostatic pressure. Furthermore, it has no means of preventing backflow through the valve if the outlet pressure exceeds the inlet pressure for any reason.

[0003] A gate valve suitable for underwater applications is disclosed in US 7 520 291 B2, which is incorporated herein by reference, and is described in Fig. 1. Briefly, the gate valve 10 includes three body portions, including a main body portion 12, an outlet body portion 14, and a pressure compensating device 76. The three body portions 12, 14, and 76 are generally rectangular parallelepipeds secured to one another by threaded engagements.

[0004] An axial passage 16 in the main body portion 12 forms an inlet 20, which may be adapted to establish a connection with a pipe or other conduit leading to a fluid reservoir or fluid pipeline whose pressure may be restricted by the valve 10. The passage 16 in the main body 12 further includes a cylindrical transverse bore 64 receiving a cylindrical seat ring 46 providing a valve seat. The seat ring 46 has a passage 48 extending axially therethrough. Meanwhile, a cylindrical bore 22 in the outlet portion 14 of the valve 10 provides a lateral passage with an outlet 18, which may be adapted, for example, to establish a flow connection with a conduit leading to a subsea well.

[0005] The inner end of the seat ring 46 projects into the axial bore 16 in the main body portion 12, and its upper edge provides a mechanical stop for positioning a valve actuator 68. The inner surface of the seat ring 46 may be planar and configured to seal with a gate or sealing disc 58 against the valve actuator 68.

[0006] In particular, a blind hole or cavity is provided in one side of the actuator 68, and a helical compression spring 60 disposed within the cavity bears at one end against the closed end of the cavity and at the other end against the spool or sealing disc 58. The pressure of the axially compressed spring 60 presses the disc 58 against the side of the seat ring 46 to seal the channel 48, as long as the disc 58 and the seat ring 46 are coaxial.

[0007] The outlet body 14 has a threaded nose portion for engagement with a corresponding socket in the side of the main body 12. A poppet valve 26 has a nose piece 28 with a seal 30 and includes a spring 29. The poppet valve 26 fits within the bore 22 of the outer body 14, and the poppet valve 26 can be brought into sealing engagement with a conical seat 24 to control the flow of the seat passage 48 out of the outlet body 18. In this manner, the poppet valve 26 acts as a check valve, ensuring that fluid flows through the valve 10 only in the intended direction.

[0008] A valve stem 52 extends coaxially from the actuator 68, and an O-ring 74 in a circumferential groove seals the stem 52 to the body of the bore 16. The pressure compensator 76 is threaded onto the main body 12 over the valve stem 52. The pressure compensator 76 includes a central axial chamber 94 in which concentric helical compression springs 102 and 104 are disposed. The upper ends of the load springs bear against a threaded cap 84, which is held in the central bore of the pressure compensator 76 by engagement with a threaded portion.

[0009] The lower ends of the load springs 102 and 104 bear against a generally circular bearing plate 96 having an inner and outer shoulder. The bearing plate 96 has a conical bushing 106 on its distal side for contact with a hemispherical end 54 of the valve stem 52.

[0010] A plug 110 has a passage 112 in fluid communication with a chamber 118 of a central extension 95 so that one side of a floating piston 88 may normally be exposed to ambient pressure, with the other side being exposed to an incompressible fluid in the chamber 94 of the compensating device.

[0011] The load springs 102 and 104 act to push the valve stem 52 into the main body portion 12 (in Fig. 1 downward) until the shoulder 72 on the actuator 68 rests on the upper edge 66 of the inner end of the seat ring 46, which projects into the passage 16. In this position, the sealing disc 58 may be coaxial with the seat ring passage 48, and the valve 10 is closed. When the inlet pressure increases sufficiently to overcome the combined force of the springs 102 and 104, the ambient pressure, and the spool-seat friction, the actuator 68 moves such that the stem 52 extends further out of the main body portion 12. This action compresses the load springs 102 and 104, expels fluid into the chamber 118 (displacing the piston 88), and moves the spool seat disc 58 out of coaxial alignment with the seat ring passage 48, thereby opening the valve 10.

[0012] A reduction in inlet pressure allows the load springs 102, 104 and the ambient pressure due to the water pressure force acting on the stem 52 to return the valve 10 to the closed position in which the passage 48 is blocked by the sealing disc 58.

[0013] Although this gate valve 10 can be effective for underwater applications, operators strive for improved performance and reliability as they encounter increasingly extreme and harsh conditions found in an underwater environment.

[0014] The subject matter of the present disclosure is directed to overcoming or at least reducing the effects of one or more of the problems identified above. SUMMARY OF REVELATION

[0015] As disclosed herein, a spool valve is used to control a flow connection from an inlet to an outlet with respect to a reference pressure. The inlet and outlet are defined within a receiving area of ​​a component. The spool valve includes a cartridge, an outlet port, a piston, a spool, and a pressure compensating device.

[0016] The cartridge is configured for positioning in the receiving area of ​​the component having the inlet and the outlet. The cartridge is arranged in sealed communication with the inlet and the outlet and defines a passage for communication with the inlet. The outlet channel is arranged in the passage and connects the passage to the outlet. The piston is arranged in the passage and is movable therein between a first and a second position relative to the outlet channel. The piston is movable in a first direction from the first position to the second position in response to an inlet pressure level at the inlet.

[0017] The spool is mounted on the piston and is biased transversely to the outlet port. The spool, moved by the piston, adjusts the flow from the passage to the outlet port. The pressure compensating device is mounted opposite the piston and biases the piston in a second, opposite direction, extending from the second position to the first position. The pressure compensating device includes a housing defining a chamber in communication with the reference pressure. The housing is configured for mounting in the receiving area and for retaining the cartridge therein.

[0018] The piston may include a proximal end disposed toward the inlet; and wherein the pressure equalization device includes a seat component separate from the housing, the seat component defining a passage for passage of a distal end of the piston therethrough.

[0019] The seat component may be located between the housing and the cartridge.

[0020] The pressure equalization device may comprise: a bearing plate movable within the chamber and engaging the distal end of the piston; and at least one spring disposed within the chamber and biasing the bearing plate toward the seat component.

[0021] The exhaust port may include a flat seating surface disposed around the exhaust port, the slide comprising: a pin disposed in a transverse hole in the piston, and a spring in the transverse hole biasing the pin against the flat seating surface.

[0022] The cartridge may define a transverse opening connecting the passage to an exterior of the cartridge. Furthermore, the outlet channel may comprise an insert sealed within the transverse opening, the insert defining a first passage therethrough connecting the passage to the exterior of the cartridge.

[0023] The spool valve may include a retaining nut mounted externally in the transverse opening and retaining the insert in the transverse opening, the retaining nut having a second passage communicating with the first passage of the insert.

[0024] The pressure equalization device may comprise a vent channel connecting the chamber to the reference pressure.

[0025] The pressure equalization device may further comprise a floating piston in the vent channel that separates internal fluid in the chamber from external fluid outside the pressure equalization device.

[0026] A spool valve according to the present disclosure is used to control the flow connection from an inlet to an outlet with respect to a reference pressure. The valve includes a first body, an outlet port, a second body, a piston, a spool, and a pressure compensating device.

[0027] The first body defines a passage communicating with the inlet at a first end of the spool valve, and the outlet port is disposed within the passage of the first body. The second body is attached to the first body. The second body defines a chamber in communication with the reference pressure. The first and second bodies define an interface therebetween that connects the outlet port to the outlet at a second end of the spool valve.

[0028] The piston is disposed in the passage and is movable therein between a first and a second position relative to the outlet port. The piston is movable in a first direction from the first position to the second position in response to an inlet pressure level at the inlet. The spool is disposed on the piston and is biased transversely toward the outlet port. The spool, moved by the piston, adjusts flow from the passage to the outlet port. The pressure compensating device is disposed in the chamber of the second body opposite the piston and biases the piston in a second opposite direction extending from the second position to the first position.

[0029] The piston may include a proximal end disposed toward the inlet; and wherein the pressure equalization device includes a seat component separate from the first and second bodies, the seat component defining a passage for passage of a distal end of the piston therethrough.

[0030] The seat component may be arranged between the first and second bodies.

[0031] The pressure equalization device may comprise: a bearing plate movable within the chamber and engaging the distal end of the piston; and at least one spring disposed within the chamber and biasing the bearing plate toward the seat component.

[0032] The exhaust port may include a flat seating surface disposed around the exhaust port, the slide comprising: a pin disposed in a transverse hole in the piston, and a spring in the transverse hole biasing the pin against the flat seating surface.

[0033] The spool valve may comprise: a first flow passage defined in the first body and connecting the outlet channel to the interface between the first and second bodies; and a second flow passage defined in the second body and connecting the interface to the outlet at the second end of the spool valve.

[0034] The interface may comprise an annular chamber formed between the first and second bodies.

[0035] The first body may define a transverse opening exposed to the passage and disposed across the first flow passage in communication with the interface.

[0036] The outlet channel may comprise an insert disposed in the transverse opening, the insert having a bore with a first opening exposed to the passage, a second opening of the bore being exposed to the transverse opening communicating with the interface via the first flow passage.

[0037] The insert can be sealed in the transverse opening.

[0038] The spool valve may include a retaining nut mounted externally in the transverse opening and holding the insert in the transverse opening.

[0039] The pressure equalization device may comprise a vent channel connecting the chamber to the reference pressure.

[0040] The pressure equalization device may further comprise a floating piston in the vent channel that separates internal fluid in the chamber from external fluid outside the pressure equalization device.

[0041] The foregoing summary is not intended to summarize every possible embodiment or aspect of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a cross-sectional view of a gate valve according to the prior art. Fig. 2A illustrates a cross-sectional view of a spool valve according to a first embodiment of the present disclosure. Fig. 2B shows a detail of Fig. 2A. Fig. 3 represents a section of the slide valve in Fig. 2A with an alternative ambient channel. Fig. 4A illustrates a cross-sectional view of a spool valve according to a second embodiment of the present disclosure. Fig. 4B shows a detail of Fig. 4A. Fig. 5 represents a section of the slide valve in Fig. 4A with an alternative ambient channel. DETAILED DESCRIPTION OF REVELATION

[0042] As in Fig. 2A, a gate valve 200 of a first embodiment is used to control the flow connection from an inlet 154 to an outlet 158 ​​of a subsea component 150. In general, the gate valve 200 may be used for a subsea application to control the flow of chemical inhibitors, such as scale, wax, and corrosion, in a subsea production system or for chemical injection applications to treat a subsea well. For example, the inlet 154 may be fluidly connected to a pipe or other conduit leading to a fluid reservoir or fluid pipeline whose pressure may be restricted by the valve 200. The outlet 158 ​​may be fluidly connected to a conduit leading to a subsea well.

[0043] The valve 200 is configured as a pocket-like valve that is installed within a pocket or receiving area 152 of the component 150. The valve 200 includes a body 202, an outlet port 280, a piston or actuator 270, a spool 290, and a pressure compensator 220. For assembly, the body 202 includes a cartridge or spool 260, a seat 250, and a compensator housing 221. The cartridge 260 fits within the receiving area 152 between the inlet 154 and the outlet 158 ​​and may be sealed therein using annular seals 261. The seat 250 fits into the receiving area 152 on the cartridge 260, and the balancer housing 221 is screwed into the receiving area 152 at an internal thread 55 for holding the seat 250 and the cartridge 260 in the receiving area 152. The seat 250, in addition to being a seat, is a seal retainer for the seal 267.

[0044] Internally, the body 202 defines a passage 262 in the cartridge 260 that is arranged to communicate with the inlet 154. The outlet channel 280 is arranged on one side of this passage 262 and connects the passage 262 to the outlet 158.

[0045] The piston 270 is disposed in the passage 262 of the cartridge 260 and is movable therein between a first and a second position relative to the outlet channel 280. In particular, the piston 270 is movable in a first direction from a first (in Fig. 2A downwards) position into a second (in Fig. 2A upward) position, as will be discussed later. (As best seen in the detail of Fig. 2B, a shoulder 264 in the passage 262 and a shoulder 276a of the piston 270 may limit the movement of the piston 270 at the second (upward) position. An opposing shoulder 276b on the piston 270, however, may engage an edge of the exhaust port 280 to limit the movement of the piston 270 at the first (downward) position.

[0046] As in Fig. 2A, the spool 290 is disposed on the piston 270 and is biased transversely to the exhaust port 280. As discussed below, during operation, the spool 290 is moved by the piston 270 and adjusts the flow through the exhaust port 280 for fluid communication from the inlet 154 to the outlet 158.

[0047] The pressure compensating device 220 is disposed opposite the piston 270 and counteracts the pressure at the inlet 154 by biasing the piston 270 in a second, opposite direction from the second (upward) position to the first (downward) position. The pressure compensating device 220 includes a chamber 222 communicating with an opening or vent 224 in the housing 221. The opening 224 is exposed to a reference pressure, which is typically ambient pressure. Thus, the pressure compensating device 220 can respond to ambient hydrostatic pressure, although other configurations are possible.

[0048] The piston 270 has a first (proximal) end 272 disposed toward the inlet 154. The pressure equalization device 220 includes the seat 250, which defines a passage 252 for the passage of a second (distal) end 274 of the piston 270. As shown, the seat 250 is disposed between the attached housing 221 and the retained cartridge 260.

[0049] The pressure equalization device 220 further includes a bearing plate 240 movable within the chamber 222. The bearing plate 240 engages the distal end 274 of the piston 270. At least one spring 230, 232 is disposed within the chamber 222 and biases the bearing plate 240 toward the seat 250.

[0050] Fig. 2B represents a section of Fig. 2A and shows the exhaust port 280 and the spool 290 in more detail. The exhaust port 280 has a flat seating surface 283 disposed around the exhaust port 280. The spool 290 is disposed in a transverse hole 279 in the piston 270 and includes a spring 292 in the transverse hole 279 that biases the spool 290 against the flat seating surface of the exhaust port 280.

[0051] According to the presentation in Fig. 2B, the outlet channel 280 includes a cylindrical seat insert 282 received in a transverse opening 265 of the cartridge 260 and providing a valve seat. The seat insert 282 has a passage 284 extending axially therethrough. The seat insert 282 abuts the shoulder of a retaining nut 268 having a channel 269 communicating externally with the cartridge 260, wherein an annular groove 56 in the receiving area 152 may communicate with the outlet 158. If a change of the seat insert 282 is desired, the retaining nut 268 may be removed and the seat insert 282 may be withdrawn so that a new seat insert 282 may be installed by the reverse procedure.

[0052] A seal 288, which may be an elastomeric O-ring, is received in an annular groove around the seat insert 282 and seals between and beneath the seat insert 282, the transverse opening 265, and the adjacent side of the retaining nut 268. This sealing arrangement reduces the possibility of fluid leaking from the valve to the atmosphere.

[0053] The inner end 283 of the insert 282 projects into an axial bore 262, and its upper edge provides a mechanical stop for positioning the piston 270, as previously noted. The inner surface 283 of the seat insert 282 may be planar and designed to seal with the spool 290 of the piston 270.

[0054] As in Fig. 2B, the blind or transverse hole 279 is provided in one side of the piston 270. The helical compression spring 292, which is disposed in the hole 279, bears at one end against the closed end of the hole 279 and at the other end against the spool 290 and may be slightly compressed when installed in the valve 200. The pressure of the axially compressed spring presses the spool 290 against the side 283 of the seat insert 282. The spool 290 may be a pin, a cylindrical disk, or the like that extends around and overlies the periphery of the passage 284 in the seat insert 282, thereby sealing the passage 284 as long as the spool 290 and the seat insert 282 are coaxial.

[0055] The outer diameter of the spool 290 may be slightly smaller than the inner diameter of the blind bore 279 so that the spool 290 can slide freely within the cavity 279 and can tilt slightly to ensure that it is coplanar with the side 283 of the seat insert 282. The force of the compression spring 292 may be very small, on the order of one ounce-force, so that the spool-seat friction due to the force of the compression spring 292 may be negligible compared to that created by the pressure of the fluid against the spool 290. For example, in certain chemical injection applications, the fluid pressure at the inlet (154) may be as high as 30,000 PSI. In these situations, the inlet fluid pressure acting across the cross-sectional area of ​​the passage 284 in the insert 282 can exert a force of up to several thousand pounds-force on the spool 290 of the valve 200.

[0056] With further reference to Fig. 2A, the distal end 274 of the piston 270 extends coaxially from the inlet 154 into a reduced-diameter portion of the cylinder bore 262. A seal 267 in a circumferential groove seals the piston 270 within the bore 262. The distal end 274 may have a larger diameter than the central passage 252 of the seat. Thus, the cross-section of the piston 270 may be larger than the area of ​​the spool 290 exposed to the pressure differential between inlet and outlet pressure. Thus, the force of fluid pressure tending to move the piston 270 within the bore 262 may be greater than the fluid force tending to hold the sealing pin 290 against the outlet port 280.It will be appreciated that since the frictional force generated between the spool 290 and the exhaust port 280 by the normal force therebetween may be only a small percentage of the normal force, variations in the frictional force due to exhaust pressure variation are reduced compared to the situation where the diameter of the piston is smaller than the diameter of the bore 284 in the insert 282.

[0057] As previously described, the pressure compensating device 220 includes the central axial chamber 222 in which concentric helical compression springs 230 and 232 are disposed. The upper ends of the load springs 230, 232 rest within the housing 221 of the compensating device 220. The lower ends of the load springs 230 and 232 rest against the bearing plate 240, which has an inner and an outer shoulder 242 for the springs 230, 232. The bearing plate 240 may have a conical bushing 244 on its opposite side for contact with a hemispherical surface of the distal end 274 of the piston 270.

[0058] The load springs 230 and 232 act to push the piston 270 into the bore 262 (in Fig. 2A down) until the shoulder (276a; Fig. 2B) on the piston 270 rests on the upper edge of the seat insert 282, which projects into the passage 262. In this position, the spool 290 may be coaxial with the insert passage 284, and the valve 200 is closed. When the inlet pressure at the inlet 154 increases sufficiently to overcome the combined force of the springs 230 and 232, the ambient pressure in the chamber 222, and the friction between the spool 290 and the insert 282, the piston 270 moves such that the distal end 274 extends further into the balance device 220. This action compresses the load spring(s) 230, 232, and expels fluid into the chamber 222 through the vent opening 224. The spool 290 moves out of coaxial alignment with the passage 284 in the seat insert 282, thereby opening the valve 200.

[0059] However, a reduction in the inlet pressure at the inlet 154 allows the load springs 230, 232 and the ambient pressure due to the water pressure force acting on the piston 270 to return the valve 200 to the closed position in which the passage 284 in the seat insert 282 is blocked by the spool 290.

[0060] The design of the valve 200 allows for direct insertion and removal of the valve 200 from the receiving area 152. Furthermore, the design of the valve 200 allows for easy replacement of components, such as those required for sealing, those subject to wear, etc. For example, with the cartridge 260 removed from the receiving area 152, the seat insert 282 for the outlet port 280 can be replaced by removing the retaining nut 268. The piston 270, the spool 290, and other elements are all removable and replaceable. The seat 250, which can provide a seal with the bearing plate 240 when the valve 200 is closed, can be replaced when the equalizer housing 221 is removed. The entire pressure equalizer 220 can be replaced. The various seals 261, 267, 288, etc., can be replaced as needed.It will be appreciated that with the benefit of the present disclosure, these and other advantages may be achieved by the valve 200 of . Fig. 2A-2B can be implemented.

[0061] Although this is Fig. 2A, the component 150 may include an outlet check valve disposed at the outlet 158 ​​for controlling the discharge from the valve 200. Namely, a check valve arrangement similar to the poppet valve 26 in Fig. 1 at the outlet 158 ​​(or at another location in the system).

[0062] Although this is Fig. 2A, the valve 200 may include components for isolating the ambient fluid at the vent opening 224 from the chamber 222 of the pressure compensation device 220. As shown in Fig. 3, the vent opening 224 may, for example, be located at the end of the housing 221. The housing 221 may include a central extension 300 having a piston chamber 302 with a floating piston 304 disposed therein. A plug 306 having a passageway may be disposed in the vent opening 224. One side of the floating piston 304 may be exposed to seawater, while the opposite side of the piston 304 is exposed to a selected hydraulic fluid that is filled into the chamber 222. In this manner, the internal fluid in the chamber 222 of the housing may be kept separate from the external fluid outside the housing 221, and the actuator piston 270 may not be exposed to the corrosive and / or contaminating effects of the seawater.

[0063] As in Fig. 4A, a spool valve 200 of a second embodiment is used to control the flow connection from an inlet to an outlet of an underwater component (not shown). Similar to the previous embodiment, the spool valve 200 includes a body 202, an outlet port 280, a piston or actuator 270, a spool 290, and a pressure equalizer 220. In assembly, the body 202 includes a cartridge or spool 260, a seat 250, and a equalizer housing 221. The seat 250 fits into one end of a chamber 222 in the equalizer housing 221, and the cartridge 260 fits into the end of the chamber 222 to hold the seat 250 in position and is sealed therein.

[0064] An adapter 160 having an outlet 158 ​​is attached to the balancer housing 221 using screws (not shown) in screw holes 223. Although this is Fig. 4A, the cartridge 260 may be attached to the housing 221 using an external thread (not shown) on the cartridge 260 that mates with an internal thread (not shown) on the housing 221. Alternatively, the cartridge 260 may be attached to the housing 221 using screws (not shown) and screw holes (not shown) provided by the Fig. 4A, be attached to the housing 221.

[0065] The cartridge 260 defines a passage 262 that may be arranged in communication with an inlet (154) of a downhole component (not shown), such as used in a subsea production system or for applications for injecting chemicals to treat a subsea well. For example, the inlet (154) of the passage 262 may be configured with suitable connectors or fittings for tubing, pipes, or hoses and is merely generally used in Fig. 4A. Likewise, the outlet 158 ​​may be configured with suitable connectors or fittings for piping, tubes, or hoses and is only generally referred to in Fig. 4A shown.

[0066] The outlet channel 280 is disposed in one side of this passage 262 and connects the passage 262 to the outlet 158 ​​of the adapter 160 in a manner discussed below.

[0067] The piston 270 is disposed in the passage 262 of the cartridge 260 and is movable therein between a first and a second position relative to the outlet channel 280. In particular, the piston 270 is movable in a first direction from a first (in Fig. 4A downwards) position into a second (in Fig. 4A upward) position, as will be discussed later. (As in Fig. 4B, a shoulder 264 in the passage 262 and a shoulder 276a on the piston 270 may limit the movement of the piston 270 at the second (upward) position. An opposing shoulder 276b on the piston 270, however, may engage an edge of the exhaust port 280 to limit the movement of the piston 270 at the first (downward) position.

[0068] As in Fig. 4A, the spool 290 is disposed on the piston 270 and is biased transversely to the outlet port 280. As discussed below, during operation, the spool 290 is moved by the piston 270 and adjusts the flow through the outlet port 280 for fluid communication from the inlet (154) to the outlet 158.

[0069] The pressure compensating device 220 is disposed opposite the piston 270 and counteracts the pressure at the inlet (154) by biasing the piston 270 in a second, opposite direction from the second (upward) position to the first (downward) position. The pressure compensating device 220 includes a chamber 222 communicating with an opening 224 in the housing 221. The opening 224 is exposed to a reference pressure, which is typically ambient pressure. Thus, the pressure compensating device 220 can respond to ambient hydrostatic pressure, but other configurations are possible.

[0070] The piston 270 has a first (proximal) end 272 disposed toward the inlet (154). The pressure equalization device 220 includes the seat 250, which defines a passage 252 for the passage of a second (distal) end 274 of the piston 270. As shown and previously noted, the seat 250 is disposed between the housing 221 and the cartridge 260.

[0071] The pressure equalization device 220 further includes a bearing plate 240 movable within the chamber 222. The bearing plate 240 engages the distal end 274 of the piston 270. At least one spring 230, 232 is disposed within the chamber 222 and biases the bearing plate 240 toward the seat 250.

[0072] Fig. 4B represents a section of Fig. 4A and shows the exhaust port 280 and the spool 290 in more detail. The exhaust port 280 has a flat seating surface 283 disposed around the exhaust port 280. The spool 290 is disposed in a transverse hole 279 in the piston 270 and includes a spring 292 in the transverse hole 279 that biases the spool 290 against the flat seating surface of the exhaust port 280.

[0073] According to the presentation in Fig. 4B, the exhaust port 280 includes a cylindrical seat insert 282 received within a transverse opening 265 of the cartridge 260 and providing a valve seat. The seat insert 282 has a passage 284 extending axially therethrough. The seat insert 282 abuts the shoulder of a retaining nut 268. If a replacement of the seat insert 282 is desired, the retaining nut 268 can be removed and the seat insert 282 can be withdrawn so that a new seat insert 282 can be installed by the reverse procedure.

[0074] A pair of seals 288, which may be elastomeric O-rings, are received in annular grooves around the seat insert 282 and seal between and beneath the seat insert 282, the transverse opening 265, and the retaining nut 268. This sealing arrangement reduces the possibility of fluid leaking from the valve to the atmosphere.

[0075] The inner end 283 of the seat insert 282 projects into an axial bore 262, and its upper edge provides a mechanical stop for positioning the piston 270, as previously noted. The inner surface 283 of the seat insert 282 may be planar and configured to seal with the spool 290 of the piston 270.

[0076] As in Fig. 4B, the blind or transverse hole 279 is provided in one side of the piston 270. The helical compression spring 292, which is disposed in the hole 279, bears at one end against the closed end of the hole 279 and at the other end against the spool 290 and may be slightly compressed when installed in the valve 200. The pressure of the axially compressed spring urges the spool 290 against the side 283 of the seat insert 282. The spool 290 may be a cylindrical disk that extends around and overlies the periphery of the passage 284 in the seat insert 282, thereby sealing the passage 284 as long as the spool 290 and the seat insert 282 are coaxial.

[0077] The outer diameter of the spool 290 may be slightly smaller than the inner diameter of the blind bore 279 so that the spool 290 can slide freely within the cavity 279 and can tilt slightly to ensure that it is coplanar with the side 283 of the seat insert 282. The force of the compression spring 292 may be very small, on the order of one ounce-force, so that the spool-seat friction due to the force of the compression spring 292 may be negligible compared to that created by the pressure of the fluid against the spool 290. For example, in certain chemical injection applications, the fluid pressure at the inlet (154) may be as high as 30,000 PSI. In these situations, the inlet fluid pressure acting across the cross-sectional area of ​​the passage 284 in the insert 282 can exert a force of up to several thousand pounds-force on the spool 290 of the valve 200.

[0078] With further reference to Fig. 4A, the distal end 274 of the piston 270 extends coaxially from the inlet (154) into a reduced diameter portion of the cylinder bore 262. A seal 267 in a circumferential groove seals the piston 270 in the bore 262. The distal end 274 may have a larger diameter than the central passage 252 of the seat. Thus, the cross-section of the piston 270 may be larger than the area of ​​the spool 290 exposed to the pressure differential between inlet and outlet pressure. Thus, the force of fluid pressure tending to move the piston 270 in the bore 262 may be greater than the fluid force tending to hold the spool 290 against the outlet port 280.It will be appreciated that since the frictional force generated between the spool 290 and the exhaust port 280 by the normal force therebetween may be only a small percentage of the normal force, variations in the frictional force due to exhaust pressure variation are reduced compared to the situation where the diameter of the piston is smaller than the diameter of the bore 284 in the insert 282.

[0079] As previously described, the pressure compensating device 220 includes the central axial chamber 222 in which concentric helical compression springs 230 and 232 are disposed. The upper ends of the load springs 230, 232 rest within the housing 221 of the compensating device 220. The lower ends of the load springs 230 and 232 rest against the bearing plate 240, which has an inner and an outer shoulder 242 for the springs 230, 232. The bearing plate 240 may have a conical bushing 244 on its opposite side for contact with a hemispherical surface of the distal end 274 on the piston 270.

[0080] The load springs 230 and 232 act to push the piston 270 into the bore 262 (in Fig. 4A down) until the shoulder (276a; Fig. 4B) on the piston 270 rests on the upper edge of the seat insert 282, which projects into the passage 262. In this position, the spool 290 may be coaxial with the insert passage 284, and the valve 200 is closed. When the inlet pressure at the inlet 154 increases sufficiently to overcome the combined force of the springs 230 and 232, the ambient pressure in the chamber 222, and the friction between the spool 290 and the insert 282, the piston 270 moves such that the distal end 274 extends further into the balance device 220. This action compresses the load spring(s) 230, 232, and expels fluid into the chamber 222 through the vent opening 224. The spool 290 moves out of coaxial alignment with the passage 284 in the seat insert 282, thereby opening the valve 200.

[0081] However, a reduction in the inlet pressure at the inlet (154) allows the load springs 230, 232 and the ambient pressure due to the water pressure force acting on the piston 270 to return the valve 200 to the closed position in which the passage 284 in the seat insert 282 is blocked by the spool 290.

[0082] Here is the valve 200 in Fig. 4A-4B, the cartridge 260 is constructed as a self-contained unit having first and second body portions 221, 260 mounted in series. The first body portion of the cartridge 260 defines the passageway 262 at one end in communication with the inlet (154) which may be adapted to connect to a pipe or other conduit leading to a fluid reservoir or conduit whose pressure may be restricted by the valve 200, and the second body portion of the compensator housing 221 defines the chamber 222 in communication with the reference port 224. The outlet channel 280 in the passageway 262 of the cartridge 260 communicates with an interface 205 between the first and second body portions 260, 221 via a first flow passage 266 in the cartridge 260.A second flow passage 226 of the second body portion 221 connects the interface 205 to an outlet chamber 228 arranged in communication with the outlet 158, which may, for example, be configured to establish a flow connection with a conduit leading to an underwater wellbore.

[0083] As in Fig. As shown in Figure 4A, the interface 205 is an annular chamber formed between the first and second body portions 260, 221, which are sealed to one another. The first and second flow passages 266, 226 are longitudinal bores extending in the first and second body portions 260, 211, respectively, to the interface 205.

[0084] How best in Fig. 4B, the first body portion 260 defines the transverse opening 265 exposed to the passageway 262 and disposed in communication with the interface 205 via the first flow passage 266. The insert 282 of the outlet channel 280, disposed in the transverse opening 265, has the central passageway 284 exposed to the passageway 262. In particular, one or more side openings 286 of the bore 282 are exposed to the transverse opening 265, which communicates with the interface 205 via the first flow passage 266. The insert 282 is sealed within the transverse opening 265 using O-rings 288 surrounding an annular groove for the side openings 286.

[0085] The design of valve 200 allows for direct insertion and removal of valve 200 between in-line connectors or ports at the inlet (154) and outlet (158). Furthermore, the design of valve 200 allows for easy replacement of components, such as those required for sealing, those subject to wear, etc. For example, seat insert 282 for outlet port 280 can be replaced by removing retaining nut 268. Piston 270, spool 290, and other elements are all removable and replaceable. Seat 250, which can provide a seal with bearing plate 240 when valve 200 is closed, can be replaced when compensator housing 221 is removed from cartridge 260. The entire pressure compensator 220 can be replaced. The various seals 267, 288, etc. can be changed as required.It will be appreciated that with the benefit of the present disclosure, these and other advantages may be achieved by the valve 200 of . Fig. 4A-4B can be implemented.

[0086] Although this is Fig. 4A, the component 150 may include an outlet check valve disposed at the outlet 158 ​​for controlling the flow out of the valve 200. Namely, a check valve arrangement similar to the poppet valve 26 in Fig. 1 at the outlet 158 ​​(or at another location in the system).

[0087] Although this is Fig. 4A, the valve 200 may include components for isolating the ambient fluid at the vent opening 224 from the chamber 222 of the pressure equalization device 220. As shown in Fig.For example, as shown in Figure 5, the housing 221 may include a central extension 300 having a piston chamber 302 with a floating piston 304 disposed therein. A plug 306 having a passage may be disposed in the vent opening 224 and may communicate with one side of the floating piston 304. In this manner, the internal fluid in the chamber 222 of the housing may be kept separate from the external fluid outside the housing 221.

[0088] The foregoing description of preferred and further embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived by the applicants. It is to be understood that, in light of the present disclosure, features described above with respect to any embodiment or aspect of the disclosed subject matter may be employed, either alone or in combination with any other described feature, in any other embodiment or aspect of the disclosed subject matter.

Claims

[1] A slide valve (200) for controlling a flow connection from an inlet (154) to an outlet (158) with respect to a reference pressure, the inlet (154) and the outlet (158) being defined in a receiving area (152) of a component (150), the slide valve comprising: a cartridge (260) configured for positioning in the receiving area (152) of the component (150) with the inlet (154) and the outlet (158), wherein the cartridge (260) is arranged in sealed communication with the inlet (154) and the outlet (158) and defines a passage (262) for communication with the inlet (154); an outlet channel (280) disposed in the passage (262) and connecting the passage (262) to the outlet (158); a piston (270) disposed in the passage (262) and movable therein between a first and a second position relative to the outlet channel (280), wherein the piston (270) is movable in a first direction from the first position to the second position in response to an inlet pressure level at the inlet (154); a slide (290) arranged on the piston (270) and biased transversely to the outlet channel (280), wherein the slide (290) moved by the piston (270) adjusts the flow from the passage (262) to the outlet channel (280); and a pressure compensating device (220) disposed opposite the piston (270) and biasing the piston (270) in a second opposite direction extending from the second position to the first position; wherein the pressure equalization device (220) comprises a housing (221) defining a chamber (222) in communication with the reference pressure, the housing (221) being configured for mounting in the receiving area (152) and for holding the cartridge (260) therein. [2] The spool valve of claim 1, wherein the piston (270) includes a proximal end (272) disposed toward the inlet (154); and wherein the pressure compensating device (220) includes a seat component (250) separate from the housing (221), the seat component (250) defining a passage for passage of a distal end of the piston (270) therethrough. [3] A slide valve according to claim 2, wherein the seat component (250) is arranged between the housing (221) and the cartridge (260). [4] A slide valve according to claim 2 or 3, wherein the pressure compensating device (220) comprises: a bearing plate (240) movable within the chamber (222) and engaging the distal end of the piston (270); and at least one spring (230) disposed within the chamber (222) and biasing the bearing plate (240) toward the seat component (250). [5] A slide valve according to any one of claims 1 to 4, wherein the outlet channel (280) comprises a flat seating surface (283) disposed around the outlet channel (280), the slide (290) comprising: a pin (290) disposed in a transverse hole (279) in the piston (270), and a spring (292) in the transverse hole (279) biasing the pin (290) against the flat seating surface (283). [6] A slide valve according to any one of claims 1 to 5, wherein the cartridge (260) defines a transverse opening (265) connecting the passage (262) to an exterior of the cartridge (260); and wherein the outlet channel (280) comprises an insert (282) sealed within the transverse opening (265), the insert (282) defining a first passage (284) therethrough in communication with the passage (262). [7] A slide valve according to claim 6, comprising a retaining nut (268) mounted externally in the transverse opening (265) and holding the insert (282) in the transverse opening (265), the retaining nut (268) having a second passage (269) communicating with the first passage (284) of the insert (282). [8] A slide valve according to claim 6, wherein first and second annular seals (261) are positioned on the outside of the cartridge (260) adjacent to the transverse opening (265), the first and second annular seals (261) being adapted to seal with the receiving area (152). [9] A slide valve according to any one of claims 1 to 8, wherein the pressure compensating device (220) comprises a vent channel (224) connecting the chamber (222) to the reference pressure. [10] The slide valve of claim 9, wherein the pressure compensating device (220) further comprises a floating piston (304) in the vent channel (224) that separates internal fluid in the chamber (222) from external fluid outside the pressure compensating device (220). [11] Slide valve according to one of claims 1 to 10, wherein the housing (221) has an external thread thereon which is designed to engage an internal thread (155) of the receiving area (152). [12] The slide valve of claim 1, wherein the cartridge (260) and the housing (221) define an interface (205) therebetween, the interface (205) connecting the outlet channel (280) at a second end of the slide valve (200) to the outlet (158). [13] The slide valve of claim 12, wherein the piston (270) includes a proximal end (272) disposed toward the inlet (154); and wherein the pressure compensating device (220) includes a seat component (250) separate from the cartridge (260) and the housing (221), the seat component (250) defining a passage for passage of a distal end of the piston (270) therethrough. [14] A slide valve according to claim 13, wherein the seat component (250) is arranged between the cartridge (260) and the housing (221). [15] A slide valve according to claim 12 or 13, wherein the pressure compensating device (220) comprises: a bearing plate (240) movable within the chamber (222) and engaging the distal end of the piston (270); and at least one spring (230) disposed within the chamber (222) and biasing the bearing plate (240) toward the seat component (250). [16] A slide valve according to any one of claims 12 to 15, wherein the outlet channel (280) comprises a flat seating surface (283) disposed around the outlet channel (280), the slide (290) comprising: a pin (290) disposed in a transverse hole (279) in the piston (270), and a spring (292) in the transverse hole (279) biasing the pin (290) against the flat seating surface (283). [17] A slide valve according to any one of claims 12 to 16, comprising: a first flow passage (266) defined in the cartridge (260) and connecting the outlet channel (280) to the interface (205) between the cartridge (260) and the housing (221); and a second flow passage (226) defined in the housing (221) and connecting the interface (205) to the outlet (158) at the second end of the slide valve (200). [18] A slide valve according to claim 17, wherein the housing (221) defines an outlet chamber (228) communicating with the second flow passage (226); and wherein the slide valve (200) includes an adapter (160) attached to the housing (221) and connecting the outlet chamber (228) to the outlet (158) at the second end of the slide valve (200). [19] A slide valve according to claim 17 or 18, wherein the interface (205) comprises an annular chamber formed between the cartridge (260) and the housing (221). [20] A slide valve according to claim 17, 18, or 19, wherein the cartridge (260) defines a transverse opening (265) exposed to the passage (262) and disposed across the first flow passage (266) in communication with the interface (205). [21] A slide valve according to claim 20, wherein the outlet channel (280) comprises an insert (282) disposed in the transverse opening (265), the insert (282) having a bore (284) with a first opening exposed to the passage (262), a second opening of the bore (286) being exposed to the transverse opening (265) communicating with the interface (205) via the first flow passage (266). [22] The slide valve of claim 21, wherein the insert (282) is sealed within the transverse opening (265); and wherein a retaining nut (268) is externally mounted within the transverse opening (265) and configured to retain the insert (282) within the transverse opening (265). [23] A slide valve according to any one of claims 12 to 22, wherein the pressure compensating device (220) comprises: a vent channel (224) connecting the chamber (222) to the reference pressure; and a floating piston (304) in the vent channel (224) separating internal fluid in the chamber (222) from external fluid outside the pressure compensating device (220).

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