Subsurface safety valve actuator

Abstract

The invention relates to a sub-surface safety valve actuation system in a well conduit comprising a safety valve, a piston assembly, a motor, a pump, a spring, a reservoir, a first valve and a second valve configured to provide a pressure in a chamber of the piston assembly driving the safety valve to an open position, to maintain a pressure in the chamber holding the safety valve in the open position, to release the pressure in the chamber via a first hydraulic release path and / or a second hydraulic release path extending through the first valve and the second valve respectively between the chamber and the reservoir, and the first and second hydraulic release paths being independent of each other such that when there is a failure in one of the first or second release paths, the pressure in the chamber holding the safety valve in the open position can be released via the other of the first or second hydraulic release paths.

Description

Technical Field

[0001] This invention generally relates to the fields of subsea drilling, processing and production equipment, and more specifically, to an improved underground safety valve actuator system. Background Technology

[0002] In subsea oil and gas exploration, drilling systems or wellheads may be located thousands of feet below the sea surface, and oil wells may extend thousands of feet below the seabed. Therefore, specialized equipment is used for drilling, producing, and processing oil and gas on the subsea, such as subsea production trees, processing systems, separators, high-integrity pipeline protection systems, drilling rigs, manifolds, fitting systems, and production and distribution systems. This equipment is typically controlled by various types of valves, including blowout preventers to prevent the accidental release of hydrocarbons into the ocean.

[0003] Subsurface safety valves (SSSVs) are typically installed in the wellbore of hydrocarbon production wells to cut off the flow of production fluids to the well surface in emergencies. These SSSVs are known to be downward-opening valves, where fluid flow within the well closes the valve, while surface pressure forces it open.

[0004] Existing SSSVs operate hydraulically from the surface, supplying pressurized hydraulic fluid to the wellhead from a surface vessel. Large hydraulic power lines from surface vessels or drilling platforms power subsea drilling, production, and processing equipment. When hydraulic pressure is applied downwards from the surface along the hydraulic line, it forces a sleeve within the SSSV to slide downwards, compressing a large spring and pushing a valve disc downwards, displacing it from the fluid passage to open the SSSV. When the hydraulic pressure is removed, the spring pushes the sleeve back, causing the baffle to close and shut off the fluid passage. In this way, the SSSV acts as a fail-safe valve, isolating the wellbore in emergency situations. Summary of the Invention

[0005] References to relevant components, portions, or surfaces of the disclosed embodiments are for illustrative purposes only and not for limiting purposes. This disclosure provides an underground safety valve actuation system (90) comprising a conduit (16, 80) disposed in a well (105) and forming a flow passage (18) leading to a surface level (104) for fluid originating below the surface level; a safety valve (91) located in the conduit (80) below the surface level (104a) and operable between an open position (FIG. 2) and a closed position (FIG. 3) to control fluid flow in the flow passage (18); and a hydraulic piston assembly (92, 192, 492) located in the conduit (80) below the surface level (104a), including a first chamber (2) and a piston (4, 404) located between the first chamber (2) and the safety valve (91). ; an electric motor (10) located in the conduit (80) below the surface level (104a) and configured to be supplied with current; a hydraulic pump (8) located in the conduit (80) below the surface level (104a) and configured to be driven by the motor (10) and connected to the first chamber (2) of the hydraulic piston assembly (92, 192, 492); a spring element (36) located in the conduit (80) below the surface level (104a) and configured to provide spring force on the piston (4, 404); a fluid reservoir (14) connected to the pump (8) and the first chamber (2); a first valve (34, 234) connected to the first chamber (2) and the fluid reservoir (14) and having a first open position ( Figure 8 , 12 14) and the first closed position ( Figure 6 , 7 11, 13, 17, 18); a second valve (35), the second valve being connected to the first chamber (2) and the fluid reservoir (14) and having a second open position ( Figure 8 , 14 ) and second closed position ( Figure 6 , 7 11, 12, 13, 17, 18); pump (8), hydraulic piston assembly (92, 192, 492), first valve (34, 234), second valve (35) and reservoir (14) are connected in a substantially closed hydraulic system (93, 193, 293, 393); wherein the hydraulic system (93, 193, 293, 393) is configured in a first state ( Figure 6 , 12), to provide pressure in the first chamber (2), the pressure driving the safety valve (91) from the closed position to the open position; wherein the hydraulic system (93, 193, 293, 393) is configured to be in a second state ( Figure 7 , 11 13, 17, 18) to maintain a pressure level in the first chamber (2) that keeps the safety valve (91) in the open position; wherein the hydraulic system (93, 193, 293, 393) is configured in a third state ( Figure 10 , 16 The system releases the pressure level in the first chamber (2) via a first hydraulic release path (6, 206 / 20 / 34 / 7, 107; 206 / 234 / 22 / 8 / 7, 107) between the first chamber (2) and the reservoir (14), the first hydraulic release path extending through the first valve (34, 234) when the first valve (34, 234) is in the first open position; wherein the hydraulic system (93, 193, 293, 393) is configured to be in a fourth state ( Figure 9 , 15 The pressure level in the first chamber (2) is released via a second hydraulic release path (6, 206 / 21 / 35 / 7, 107) extending through the second valve (2) between the first chamber (2) and the reservoir (14) when the second valve (35) is in the second open position; and wherein the first hydraulic release path (6, 206 / 20 / 34 / 7, 107; 206 / 234 / 22 / 8 / 7, 107) is independent of the second hydraulic release path (6, 206 / 21 / 35 / 7, 107), and the second hydraulic release path (6, 206 / 21 / 35 / 7, 107) is independent of the first hydraulic release path (6, 206 / 20 / 34 / 7, 107). 7, 107; 206 / 234 / 22 / 8 / 7, 107); Thus, the pressure level in the first chamber (2) holding the safety valve (91) in the open position can be released via the first hydraulic release path (6, 206 / 20 / 34 / 7, 107; 206 / 234 / 22 / 8 / 7, 107) when there is a fault in the second hydraulic release path (6, 206 / 21 / 35 / 7, 107), and can be released via the second hydraulic release path (6, 206 / 21 / 35 / 7, 107) when there is a fault in the first hydraulic release path (6, 206 / 20 / 34 / 7, 107; 206 / 234 / 22 / 8 / 7, 107).

[0006] The hydraulic system (93, 193, 293, 393) can be configured in a second state ( Figure 7 ,11 (13, 17, 18) to maintain the pressure level in the first chamber (2) without relying on the motor (10) and pump (8). Second state ( Figure 7 , 11 (13, 17, 18) may include a first valve (34, 234) in a first closed position and a second valve (35) in a second closed position.

[0007] In the second state, the spring element (36) can be compressed between the piston (4, 404) and the pipe (66). Figure 7 , 11 13, 17, 18). The hydraulic piston assembly (192) can consist essentially of a first chamber (2) connected to a closed hydraulic system.

[0008] The first hydraulic release path (206 / 234 / 22 / 8 / 7, 107) can extend through the pump (8). First state ( Figure 12 This may include providing a hydraulic pressure on the piston (4, 404) that is opposite to and exceeds the spring force, and the piston (4, 404) translates in a first direction and actuates the safety valve (91) to the open position. First state ( Figure 12 The pump (8) may include a first valve (234) in a first open position and drive a motor (10) to control fluid flow through the pump (8) to the first chamber (2). A second hydraulic release path (206 / 21 / 35 / 7, 107) may be independent of the pump (8). First state ( Figure 12 It may include a first valve (234) in a first open position and a second valve (35) in a second closed position.

[0009] The hydraulic piston assembly (92, 492) may include a second chamber (3) connected to a fluid reservoir (14); a piston (4, 404) may separate the first chamber and the second chamber; and a positive pressure differential between the first chamber (2) and the second chamber (3) may provide a hydraulic pressure on the piston (4, 404) that is opposite to and exceeds the spring force. A negative pressure differential between the first chamber (2) and the second chamber (3) may provide a hydraulic pressure on the piston in a second direction opposite to the first direction. A third state may include a negative pressure differential, and the resulting hydraulic pressure and spring force cause the piston (4, 404) to translate in the second direction, thereby actuating the safety valve (91) to the closed position.

[0010] Second state ( Figure 13 , 17 18) may include providing a hydraulic pressure on the piston (4, 404) that is opposite to and at least equal to the spring force. Second state ( Figure 13 , 1718) may include a first valve (234) in a first closed position. A second hydraulic release path (6, 206 / 21 / 35 / 7, 107) may be independent of the pump (8). Second state ( Figure 13 , 17 18) may include a second valve (35) in the second closed position.

[0011] Third state ( Figure 16 This may include providing a hydraulic pressure on the piston (4, 404) opposite to the spring force, which is less than the spring force, causing the piston to translate in a second direction opposite to the first direction and actuate the safety valve (91) to the closed position. The second hydraulic release path (6, 206 / 21 / 35 / 7, 107) may be independent of the pump (8). The third state ( Figure 16 The third state may include a second valve (35) in a fault-closed state. The third state may include a drive motor (10) to control the fluid flow rate in the first hydraulic release path (206 / 234 / 22 / 8 / 7, 107). The third state may include releasing the motor (10) and pump (8) to allow fluid to flow in the first hydraulic release path (206 / 234 / 22 / 8 / 7, 107). The third state may include a second valve (35) in a second closed position and release the motor (10) and pump (8) to allow fluid to flow in the first hydraulic release path (206 / 234 / 22 / 8 / 7, 107). The third state may include a second valve (35) in a second closed position and drive the motor (10) to control the fluid flow rate in the first hydraulic release path (206 / 234 / 22 / 8 / 7, 107).

[0012] Fourth state ( Figure 15 This may include providing a hydraulic pressure on the piston (4, 404) opposite to the spring force, which is less than the spring force, causing the piston (4, 404) to translate in a second direction opposite to the first direction, and actuating the safety valve (91) to the closed position. Fourth state ( Figure 15 It may include a first valve (234) in the fault-closed position and / or a pump in the fault-blocked flow position.

[0013] The first hydraulic release path (6, 206 / 20 / 34 / 7, 107) can be independent of the pump (8), while the second hydraulic release path (6, 206 / 21 / 35 / 7, 107) can be independent of the pump (8). First state ( Figure 6 This may include providing a hydraulic pressure on the piston (4, 404) that is opposite to and exceeds the spring force, and the piston (4, 404) translates in a first direction and actuates the safety valve (91) to the open position. First state ( Figure 6The device may include a first valve (34) in a first closed position, a second valve (35) in a second closed position, and a drive motor (10) to control the flow of fluid through the pump (8) to the first chamber (2).

[0014] The hydraulic piston assembly (92, 492) may include a second chamber (3) connected to a fluid reservoir (14); a piston (4, 404) may separate the first chamber and the second chamber; and a positive pressure differential between the first chamber (2) and the second chamber (3) may provide a hydraulic pressure on the piston (4, 404) that is opposite to and exceeds the spring force. A negative pressure differential between the first chamber (2) and the second chamber (3) may provide a hydraulic pressure on the piston in a second direction opposite to the first direction. A third state may include a negative pressure differential, and the resulting hydraulic pressure and spring force cause the piston (4, 404) to translate in the second direction, thereby actuating the safety valve (91) to the closed position.

[0015] Second state ( Figure 7 This may include providing a hydraulic pressure on the piston (4, 404) that is opposite to and at least equal to the spring force. Second state ( Figure 7 The system may include a first valve (34) in a first closed position and a second valve (35) in a second closed position. The actuation system may include a check valve (24) between the pump (8) and the first chamber (2), the check valve being operably arranged to allow fluid to flow from the pump (8) to the first chamber (2) and to prevent fluid from flowing from the first chamber (2) to the pump (8), thereby maintaining the pressure level in the first chamber (2) independently of the motor (10) and the pump (8).

[0016] Third state ( Figure 10 This may include providing a hydraulic pressure on the piston (4, 404) opposite to the spring force, which is less than the spring force, causing the piston (4, 404) to translate in a second direction opposite to the first direction, and actuating the safety valve (91) to the closed position. Third state ( Figure 10 The third state may include a second valve (35) in the fault-closed position.

[0017] Fourth state ( Figure 9 This may include providing a hydraulic pressure on the piston (4, 404) opposite to the spring force, which is less than the spring force, and the piston (4, 404) translating in a second direction opposite to the first direction, actuating the safety valve (91) to the closed position. Fourth state ( Figure 9 The fourth state may include the first valve (34) in the fault-closed position.

[0018] The actuation system may include a third hydraulic release path (6 / 22 / 8 / 7, 107) located between the first chamber (2) and the reservoir (14), which extends through the pump (8) when the motor (10) and the pump (8) are released to allow fluid to flow in the third hydraulic release path (6 / 22 / 8 / 7, 107); and the third hydraulic release path (6 / 22 / 8 / 7, 107) may be independent of the first hydraulic release path (6, 206 / 20 / 34 / 7, 107) and the second hydraulic release path (6, 206 / 21 / 35 / 7, 107). The actuation system can be configured to be in a fifth state to release the pressure level in the first chamber (2) via a third hydraulic release path (6 / 22 / 8 / 7, 107) between the first chamber (2) and the reservoir (14), the third hydraulic release path extending through the pump (8) when the motor (10) and the pump (8) are released to allow fluid to flow in the third hydraulic release path (6 / 22 / 8 / 7, 107).

[0019] The fluid reservoir (13) may include a pressure compensator (15 / 16) configured to normalize the pressure difference between the outside and inside of the hydraulic system. The pressure compensator may include a diaphragm or piston (15). The actuation system may include a position sensor (53) configured to sense the position of the diaphragm or piston (15).

[0020] The first valve (34, 234) may include an active actuation valve arranged to open and allow equalization of fluid pressure on each side of the first valve, and the second valve (35) may include an active actuation valve arranged to open and allow equalization of fluid pressure on each side of the second valve. The first valve (34, 234) may include a solenoid valve arranged to open in the event of a power failure, thereby allowing equalization of fluid pressure on each side of the first valve, and the second valve (35) may include a solenoid valve arranged to open in the event of a power failure, thereby allowing equalization of fluid pressure on each side of the second valve.

[0021] The conduit (80) may include an outer tubular surface (81) oriented about a longitudinal axis (xx); an inner tubular surface (82) oriented about the longitudinal axis and defining the flow passage (18); a first module cavity (84) between the inner tubular surface (82) and the outer tubular surface (81); a second module cavity (83) between the inner tubular surface (82) and the outer tubular surface (81); a hydraulic piston assembly (92) may be disposed in the first module cavity (84); and a motor (10) and a pump (8) may be disposed in the second module cavity (83).

[0022] The safety valve may include: a baffle element (61) configured to rotate about a hinge axis (62) between an open position and a closed position in a flow channel (18); the hinge axis (62) being fixed relative to the conduit (80); and a baffle actuation sleeve (64) oriented about the longitudinal axis and configured to move the baffle element (61) in the flow channel (18) from the closed position to the open position.

[0023] The hydraulic piston assembly (92, 192) may include a first actuator rod (5, 405b) connected to the piston (4, 404) for movement with the piston, a first actuator collar (60) connected to the actuator rod (5, 405b) for movement with the actuator, and a baffle actuation sleeve (64) connected to the actuator collar (60) for movement with the actuator. A spring element (36) may be compressed between the piston (5, 405) and the tube (80, 66) in a second state, and may include a helical spring (36) oriented about a longitudinal axis and axially positioned between the hinge axis (62) and the first actuator collar (60).

[0024] The hydraulic piston assembly (92, 492) may include a second chamber (3) connected to a fluid reservoir (14), and a piston (4, 404) that can separate the first chamber and the second chamber. The piston (4, 404) may include a first surface area (4a, 404a) exposed to the first chamber (2) and a second surface area (4b, 404b) exposed to the second chamber (3). The first surface area (4a, 404a) may be equal to or greater than the second surface area (4b, 404b). The hydraulic piston assembly (92, 492) may include a hydraulic cylinder (9, 409) having a first end wall (9b, 409b), and a piston (4, 404) may be disposed in the hydraulic cylinder (9, 409) for sealing sliding along the hydraulic cylinder (9, 409); and the hydraulic piston assembly (92, 492) may include a first actuator rod (5, 405b) connected to the piston (4, 404) to move with the piston, and having a portion that sealably penetrates the first end wall (9b, 409b). The hydraulic cylinder (409) may have a second end wall (409a), and the hydraulic piston assembly (492) may include a second actuator rod (409a) connected to the piston (404) to move with it and having a portion that sealably penetrates the second end wall (409a), and the first surface area (405a) may be equal to the second surface area (405b).

[0025] The actuation system may include an underground control electronics (95) below the surface level and connected to a motor (10), a first valve (34, 234) and a second valve (35); a surface controller (11) located above the surface level (103); a power cable (12) supplying power from the surface level (103) to the underground control electronics (95); and a communication cable (12) between the underground control electronics (95) and the surface controller (11).

[0026] The actuation system may include multiple sensors (40a, 40b, 53) configured to sense operating parameters of the system. The underground control electronics (95) may include a signal processor communicating with the sensors (40a, 40b, 53) and is configured to receive sensor data from the sensors (40a, 40b, 53) and output the data to the surface controller (11) via a communication cable (12). The actuation system may include a position sensor configured to sense the position of the piston (4), and the position sensor may include a first contact switch (40a) and a second contact switch (40b).

[0027] The electric motor (10) may include a variable speed electric motor, and the hydraulic pump (8) may include a reversible hydraulic pump. The hydraulic pump may be selected from the group consisting of a fixed displacement pump, a variable displacement pump, a two-port pump, and a three-port pump.

[0028] The actuation system may include an underground controller (74) located below the surface level (104) and connected to a motor (10), a first valve (34), and a second valve (35); underground sensors (40a, 40b, 53, 153, 43, 44, 41) located below the surface level (104), configured to sense operating parameters of components (92, 13, 34, 35) of the actuation system (90) and connected to the controller (74); and the underground controller (74) The underground controller (74) may include a non-transitory computer-readable medium storing one or more instructions that can be executed by the underground controller (74) to perform diagnostic tests (210, 300, 400, 400b, 400c) on components (92, 13, 34, 35) of the actuation system, the diagnostic tests being functions of operating parameters of the components (92, 13, 34, 35) of the actuation system sensed by the underground sensors (40a, 40b, 53, 153, 43, 44, 41). The fluid reservoir (13) may include a pressure compensator (13), and the components of the actuation system may be selected from the group consisting of a pressure compensator (13), a hydraulic piston assembly (92), a first valve (34), and a second valve (35); and the underground sensors may be selected from the group consisting of position sensors (40a, 40b, 53, 153), a current sensor (76), and a pressure sensor (41).

[0029] The underground sensors include position sensors (40a, 40b) configured to sense the position of pistons (4, 60) of a hydraulic piston assembly (92). Diagnostic testing (210) may include: commanding pistons (4, 60) to move (212, 215) to a preset position; monitoring (216) the position sensors (40a, 40b) after the commanded movement (212, 215); and determining (213, 217) the operating state (222, 219, 220) of the hydraulic piston assembly (92) based on the output or absence of the monitored position sensors (40a, 40b). The step of determining the operating state of the hydraulic piston assembly may be a function of a threshold elapsed time (214, 218) from the start of the commanded movement.

[0030] The pressure compensator (13) may include a compensator diaphragm or a compensator piston (15), and the underground sensor may include a position sensor (53, 153) configured to sense the position of the compensator diaphragm or the compensator piston (15). The diagnostic test (300) may include: commanding the piston (4, 60) of the hydraulic piston assembly (92) to move (302, 305) to a preset position; monitoring (306) the compensator position sensor (53, 153) after the commanded movement (302, 305); and determining (314) the operating state (315, 316) of the pressure compensator (13) based on the output or absence of output from the monitored compensator position sensor (53, 153). The step of determining the operating state of the pressure compensator may be a function of a threshold elapsed time (308) from the start of the commanded movement.

[0031] The first or second valve (34, 35) may include a solenoid valve configured to open in the event of a power failure, allowing for equalization of fluid pressure on both sides of the valve. The underground sensor may include a current sensor (76) configured to sense the current of the solenoid valve. The diagnostic test (400) may include: commanding (405) energizing the solenoid valve; monitoring (406) the current sensor (76) after the command to energize; and determining (408) the operating state of the solenoid valve (409, 410) based on the output of the monitored current sensor (76). The step of determining the operating state of the solenoid valve may be a function of current reference data stored in the underground controller (74). The first or second valve (34, 35) may include a solenoid valve arranged to open in the event of a power failure, thereby allowing equalization of fluid pressure on each side of the valve. The underground sensor may include a valve position sensor (43, 44) configured to sense the position of the solenoid valve, and the diagnostic test (400b) may include: commanding (405b) the solenoid valve to be energized; monitoring (406b) the valve position sensor (43, 44) after the command to be energized; and determining (408b) the operating state of the solenoid valve (409b, 410b) based on the output or absence of the monitored valve position sensor (43, 44). The first or second valve may include a solenoid valve arranged to open in the event of a power failure, thereby allowing equalization of fluid pressure on each side of the first valve. The pump (8) may include a rotary pump. The underground sensor may include a pressure sensor (41) configured to sense pressure in a closed hydraulic system (93). The diagnostic test (400c) may include: commanding the solenoid valve to de-energize (403, 409c, 413c); commanding (405c) the rotary pump to rotate at a reference rotational speed; monitoring (404c) the pressure sensor (41) after the solenoid valve is commanded to de-energize; and determining (406c, 408c, 410c, 412c, 414c, 416c) the operating state of the solenoid valve (419c, 420c, 421c, 418c) based on the output from the monitored pressure sensor (41). The step of determining the operating state of the solenoid valve may be a function of stored pressure reference data. Diagnostic tests (400c) may include: energizing the solenoid valve with commands (407c, 411c, 415c); and monitoring the pressure sensor (404c) after the solenoid valve is energized. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a subsea oil well assembly with an improved safety valve actuator system in an underground production line.

[0033] Figure 2 is Figure 1An enlarged schematic diagram of an embodiment of the safety valve actuator system in the open position.

[0034] Figure 3 is Figure 1 An enlarged schematic diagram of an embodiment of the safety valve actuator system shown in the closed position.

[0035] Figure 4 It is a horizontal cross-sectional view of the component shown in Figure 3, taken roughly along line AA in Figure 3.

[0036] Figure 5 yes Figure 1 A detailed schematic diagram of an embodiment of the safety valve actuator system shown.

[0037] Figure 6 yes Figure 5 A detailed schematic diagram of the hydraulic system of an embodiment of the safety valve actuator system shown, in the valve open state.

[0038] Figure 7 yes Figure 6 A detailed schematic diagram of the hydraulic system of an embodiment of the safety valve actuator system shown, with the valve held open.

[0039] Figure 8 yes Figure 6 A detailed schematic diagram of the hydraulic system of an embodiment of the safety valve actuator system shown, in the valve closed state.

[0040] Figure 9 yes Figure 6 The hydraulic system of the embodiment of the safety valve actuator system shown is a detailed schematic diagram of the valve closed when it has a first fault condition.

[0041] Figure 10 yes Figure 6 The hydraulic system of the embodiment of the safety valve actuator system shown is illustrated in detail when the valve is closed with a second fault condition.

[0042] Figure 11 yes Figure 6 A detailed schematic diagram of a second embodiment of the hydraulic system of the safety valve actuator system shown, illustrating a single-chamber hydraulic piston configuration.

[0043] Figure 12 yes Figure 6 The diagram shows a detailed schematic of the third embodiment of the hydraulic system of the safety valve actuator system in the valve open state.

[0044] Figure 13 yes Figure 12 The diagram shows a detailed schematic of the hydraulic system of an embodiment of the safety valve actuator system in the valve-open state.

[0045] Figure 14 yes Figure 12 The diagram shows a detailed schematic of the hydraulic system of an embodiment of the safety valve actuator system in the valve closed state.

[0046] Figure 15 yes Figure 12 The hydraulic system of the embodiment of the safety valve actuator system shown is illustrated in detail when the valve is closed with a first fault condition.

[0047] Figure 16 yes Figure 12 The hydraulic system of the embodiment of the safety valve actuator system shown is illustrated in detail when the valve is closed with a second fault condition.

[0048] Figure 17 yes Figure 6 A detailed schematic diagram of a fourth embodiment of the hydraulic system of the safety valve actuator system shown, illustrating a single-chamber hydraulic piston configuration.

[0049] Figure 18 yes Figure 6 A detailed schematic diagram of the fifth embodiment of the hydraulic system of the safety valve actuator system shown in the diagram illustrates equal piston areas and a double-rod configuration.

[0050] Figure 19 yes Figure 5 A cross-sectional view of an embodiment of the bidirectional pump shown.

[0051] Figure 20 yes Figure 5 The diagram shows a cross-sectional view of an electric variable speed bidirectional motor.

[0052] Figure 21 It is shown Figure 5 A flowchart illustrating an embodiment of the hydraulic cylinder diagnostic function of the safety valve actuator system.

[0053] Figure 22 It is shown Figure 5 A flowchart illustrating an embodiment of the compensator diagnostic function of the safety valve actuator system.

[0054] Figure 23 It is shown Figure 5 A flowchart of the first embodiment of the solenoid diagnostic function of the safety valve actuator system shown.

[0055] Figure 24 It is shown Figure 5 A flowchart of a second embodiment of the solenoid diagnostic function of the safety valve actuator system shown.

[0056] Figure 25 It is shown Figure 5A flowchart of the third embodiment of the solenoid diagnostic function of the safety valve actuator system shown. Detailed Implementation

[0057] First, it should be clearly understood that in the several figures, the same reference numerals are intended to consistently identify the same structural elements, portions, or surfaces, as these elements, portions, and surfaces can be further described or explained throughout the written specification, of which this detailed description is an integral part. Unless otherwise stated, the figures are intended to be read in conjunction with the specification (e.g., crosshairs, arrangement of parts, scale, extent, etc.) and are considered part of the entire written description of the invention. As used in the following description, the terms “horizontal,” “vertical,” “left,” “right,” “up,” and “down,” as well as their adjective and adverbial derivatives (e.g., “lateral,” “rightward,” “upward,” etc.), refer only to the orientation of the structure shown when the particular figure is facing the reader. Similarly, the terms “inward” and “outward” generally refer to the orientation of a surface relative to its axis of extension or axis of rotation (as the case may be).

[0058] Now refer to the attached diagram, and more specifically to the attached diagram. Figure 1 This disclosure broadly provides a surface-controlled subsurface safety valve (SCSSV), an embodiment of which is indicated by 90. The subsurface safety valve 90 is used in a production system comprising a platform 100 floating on a sea surface 103 and a production line 101 extending from a seabed wellhead 102 to the platform 100 at a distance 103a below the sea surface 103. A borehole 105 extends from a seabed 104 to a point below the seabed 104. The borehole is lined with casing and a production line 16 to form a wellbore 18, which provides fluid communication between the wellbore 18 and the surrounding hydrocarbon-bearing formation. The subsurface safety valve 90 is positioned at a distance 104a in the oil line 16 to stop the flow of production fluid in the subsurface line 16 when needed, such as in an emergency. The subsurface safety valve 90 operates in a fail-safe mode, with hydraulic control pressure used to keep a baffle valve 91 open, and such that if the control pressure is lost, the baffle valve 91 will close, thereby blocking fluid from the wellhead 102.

[0059] The surface controller 11 on platform 100 communicates with the in-well control electronics 95 via power and data cables 12. In an emergency, the surface controller 11 can issue a valve closing command to the in-well control electronics 95, and this command may include de-energizing the control electronics 95 and the underground safety valve 90. The surface controller 11 can also store and relay sensing data from the underground safety valve 90, and otherwise provide a user interface for viewing the sensing data and setting operating parameters. The processor may include data sampling and storage mechanisms for receiving and storing sensing data, and may include a data storage device for storing operating parameters and sensing data logs.

[0060] As shown in Figure 2 and Figure 5 As shown, the underground safety valve 90 typically includes a motor and pump assembly or module 94, a hydraulic manifold assembly or module 93, a system pressure compensation reservoir assembly or module 13, a hydraulic piston actuator assembly or module 92, a safety valve assembly or module 91, and in-well control electronics 95. Each of these modules is housed in a conduit 16.

[0061] As shown in Figures 2-4, in this embodiment, a portion 80 of the conduit 16 houses a motor and pump assembly 94, a hydraulic manifold assembly 93, a system pressure compensation reservoir assembly 13, a hydraulic piston actuator assembly 92, and in-well control electronics 95 between the outer cylindrical surface 81 and the inner cylindrical surface 82 of the conduit portion 80. In this embodiment, portion 80 includes a circumferentially spaced and longitudinally extending first cavity 83 and a circumferentially spaced and longitudinally extending second cavity 84. In this embodiment, the compensation reservoir assembly 13, the motor and pump assembly 94, and the control electronics 95 are stacked in cavity 83, with the control electronics located on top of and sealed to the compensation reservoir assembly 13 and the motor and pump assembly 94. The hydraulic manifold assembly 93 and the hydraulic piston actuator assembly 92 are stacked in cavity 84. A fluid conduit 85 extends through the portion 80 in cavity 83 between the compensation reservoir assembly 13 and the motor and pump assembly 94, and through the portion in cavity 84 between the hydraulic manifold assembly 93 and the hydraulic piston actuator assembly 92.

[0062] The pump and motor assembly 94 typically includes a variable-speed bidirectional electric servo motor 10 and a bidirectional or reversible pump 8 driven by the motor 10. For example... Figure 20 As further detailed below, in this embodiment, motor 10 is a brushless DC variable-speed servo motor supplied with current. Motor 10 has an inner rotor 50 with permanent magnets and a fixed, non-rotating stator 51 with coil windings. When a suitable current is applied through the coils of stator 51, a magnetic field is induced. The interaction of the magnetic fields between stator 51 and rotor 50 generates torque that can rotate output shaft 52. Drive electronics 71 generates and commutates the stator field based on position feedback to change the speed and direction of motor 10. Therefore, motor 10 will selectively apply torque to shaft 52 at varying speeds in one direction about axis x, and will apply torque to shaft 52 at different speeds in the opposite direction about axis x. Other motors can be used as alternatives. For example, a variable-speed stepper motor, a brushed motor, or an induction motor can be used.

[0063] like Figure 19As further detailed below, in this embodiment, pump 8 is a fixed-displacement bidirectional internal dual-port gear pump. The pumping elements, namely gears 55 and 56, are rotatable in either direction, allowing hydraulic fluid to flow in either direction 47 or 48. This allows oil to be added to and discharged from the system when the system controller is in a closed position or when the pressure control loop is open. The shaft of gear 55 is connected to the output shaft 52 of motor 10, with another pump gear 56 following immediately behind. Fluid is directed to flow between the outer gear teeth of gears 55 and 56 and the housing 57 to the outside of gears 55 and 56, respectively. Therefore, rotation of gear 55 in a clockwise direction 46 causes fluid to flow from port 8a to port 8b in one direction 48. Rotation of gear 55 in a counterclockwise direction 45 causes fluid to flow from port 8b to port 8a in the opposite direction 47. Thus, the flow direction of pump 8 depends on the rotational direction of rotor 50 and output shaft 52 about axis x. Furthermore, the speed and output of pump 8 vary with the speed of electric motor 10. Other bidirectional pumps may be used as alternatives. For example, a variable displacement pump can be used.

[0064] The in-well electronics 95 receives commands, such as valve opening or closing commands, and power from the surface level controller 11 via cable 12. The in-well electronics 95 includes a controller 74, a power distribution unit 70, motor controller drive electronics 71 for controlling and reversing the motor 10, and solenoid drive electronics 72 for actuating and controlling solenoid valves 34 and 35. The controller 74 receives feedback from sensors in the system via a sensor interface 73. The controller 74 communicates with the surface level control electronics 11 via data and power cables 12.

[0065] In this embodiment, position sensors 40a and 40b monitor the position of the sleeve ring 60 fixed to the end of the rod 5 of the piston assembly 92, and then feed the position signal back to the controller 74. Although position sensors 40a and 40b are shown as limit switches in this embodiment, other position sensors can be used as alternatives, and such position sensors can be placed in alternative locations within the assembly. For example, but not limited to, magnetostrictive linear position sensors or LVDT position sensors can be used as alternatives.

[0066] As shown in Figures 2 and 6, the hydraulic piston assembly 92 includes a piston 4 slidably disposed within a cylindrical housing 9. A rod 5 is mounted on the piston 4 to move with it and extends to the right, sealingly passing through the right end wall 9b of the hydraulic cylinder 9. The piston 4 is slidably disposed within the hydraulic cylinder 9 and sealably separates the left chamber 2 from the right chamber 3. In this embodiment, almost all of the left-facing circular vertical end face 4a of the piston 4 faces the left chamber 2. However, due to the addition of the rod 5 passing through the chamber 3 and the housing 9, only the right-facing annular vertical end face 4b of the piston 4 faces the right chamber 3. This results in an unequal piston area configuration, where the surface area of ​​face 4a is larger than the surface area of ​​face 4b.

[0067] In this embodiment, the reservoir module 13 typically includes a piston-type pressure compensator for sealing the hydraulic fluid system. As shown, the reservoir 13 is divided into two variable-volume chambers 14 and 16 by a piston 15, which is slidably disposed within a cylindrical housing. When the system fluid is moved, the piston 15 moves and moves the contents of the chamber 16 on the other side. The piston 15 moves within the housing to ensure that the fluid inside is substantially equal to the ambient pressure outside the system. The chamber 16 is open to the external environment, and the chamber or tank 14 serves as a hydraulic reservoir for the system fluid and is sealed and pressure balanced with the external environment 16 by the piston 15. As shown, in this embodiment, the reservoir module 13 includes a position sensor 53 configured to sense the position of the piston 15 within the cylindrical housing and communicate with the controller 74. In this embodiment, the sensor 53 is an LVDT position sensor.

[0068] Alternatively, but not limited to, reservoir 13 may employ a bladder-type pressure compensator for fluid systems instead of a piston-type pressure compensator. This compensator typically functions the same as the piston-type, except that the barrier between the system fluid in tank 14 and the external environment in chamber 16 is an elastic bladder or diaphragm. The bladder is easily movable and ensures that the internal fluid pressure is substantially equal to the external environmental pressure.

[0069] As shown in Figures 2 and 3, the well safety valve 91 typically includes a baffle 61 rotatable about a hinge 62 to enter and exit a flow passage 18, a valve actuation sleeve 64 connected to one end of a rod 5 via an annular sleeve ring 60, an annular spring stop 66 acting in the production oil pipeline 16, and a spring 36 fixed between the rod 5 and the sleeve ring 60. The spring stop 66 is fixed to the pipeline 16 relative to the baffle hinge 62, and the valve actuation sleeve 64 slides freely axially within the pipeline 16 relative to the hinge 62 as the piston 4 moves axially within the hydraulic cylinder 9. The spring 36 is compressed between the annular spring stop 66 and the annular sleeve ring 60 in the pipeline 16.

[0070] Piston 4, via piston rod 5, can be driven to force sleeve 64, via sleeve collar 60, to slide downward within conduit 16, compressing spring 36 and pushing valve disc 61 downward counterclockwise about hinge 62, away from fluid passage 18 to open valve assembly 91. Spring 36 is configured to bias rod 5 toward a retracted position and safety valve 91 toward a closed position via sleeve collar 60, which is connected to and moves with the rod 5 of piston assembly 92 and the cylindrical sleeve 64 of valve assembly 91. Therefore, when hydraulic pressure is removed from chamber 2 of piston 4, spring 36 provides a spring force that drives sleeve 64 upward via collar 60, allowing baffle 61 to shut off and close fluid passage 18. Baffle valve 61 is oriented to open downward and close upward, such that upward fluid flow in well passage 18 will act as an upward push on baffle 61 about hinge axis 62 to shut off or close. Therefore, when valve assembly 91 needs to be closed, for example in an emergency, spring 36 is configured to provide a spring force that drives the cylindrical sleeve 64 upward to a position that allows baffle 61 to rotate upward about hinge axis 62 and enter flow passage 18, thereby preventing upward flow through production line 16. In this way, valve assembly 91 is a fail-safe valve that can be operated to isolate wellbore 18 in an emergency.

[0071] The hydraulic manifold 93 of the first embodiment is as follows: Figure 5-10 As shown in the figure, the hydraulic manifold 93 typically includes a solenoid valve 34, a solenoid 35, and multiple hydraulic lines 6, 7, 20, 21, and 22. The pump 8, chamber 2, chamber 3, tank 14, valve 34, valve 35, and hydraulic flow lines 6, 7, 20, 21, and 22 form a closed fluid system.

[0072] In this embodiment, valves 34 and 35 are active valves that are opened or closed by external actuation, rather than passive valves whose opening or closing state is determined by the fluid controlled by the valve (e.g., a check valve). In this embodiment, valves 34 and 35 are bidirectional two-port solenoid valves. When valves 34 and 35 are energized, the valves maintain the blocked port and are closed, thereby blocking flow through the valves in either direction. When valves 34 and 35 are de-energized, the springs of the solenoid valves return them to the open position, thereby allowing fluid pressure to be equalized on both sides of the valve and flow through the valve in either direction. Therefore, in the event of a power failure, valves 34 and 35 will open, allowing fluid pressure to be equalized on each side of the valve.

[0073] like Figure 6-10As shown, in hydraulic manifold embodiment 93, pump 8 is located in fluid line 22. One side or port 8a of pump 8 is connected to left chamber 2 via fluid lines 22 and 6, and the opposite side or port 8b of pump 8 is connected to right chamber 3 via fluid lines 22 and 7. Port 8b of pump 8 is connected to tank 14 via fluid lines 22 and 7. Right chamber 3 is connected to tank 14 via fluid line 7. Bypass fluid line 20 connects lines 6 and 7, and thus connects chamber 2 to tank 14 and chamber 3. Solenoid valve 34 is disposed in line 20. Bypass fluid line 20 and solenoid valve 34 are disposed in line 6 between side 8a of pump 8 and left chamber 2, thus providing a first fluid line between chamber 2 and tank 14 that bypasses pump 8 and is independent of pump 8. Bypass fluid line 21 also connects lines 6 and 7, and thus also connects chamber 2 to tank 14 and chamber 3. Solenoid valve 35 is disposed in line 21. A bypass fluid line 21 and solenoid valve 35 are disposed in line 6 between side 8a of pump 8 and left chamber 2, thus providing a second fluid line between chamber 2 and storage tank 14, which bypasses pump 8 and is independent of pump 8. Therefore, line 22 having pump 8, line 20 having valve 34, and line 21 having valve 35 form a parallel hydraulic flow connection between chamber 2 and tank 14. Therefore, solenoid valve 34 and fluid line 20 are operably configured to provide a first hydraulic release path between chamber 2 and storage tank 14. Solenoid valve 35 and fluid line 21 are operably configured to provide a second hydraulic release path between chamber 2 and storage tank 14. Furthermore, if desired, fluid line 22 and pump 8 can be configured to operably provide a third hydraulic release path between chamber 2 and storage tank 14.

[0074] The system in this embodiment can be controlled in at least two operating states and at least two fail-safe states. For example... Figure 6As shown, in order to extend rod 5 and open safety valve assembly 91, valve 34 is energized such that valve 35 is in a blocked port and closed, and valve 35 is energized such that valve 35 is in a blocked port and closed. Therefore, side 8a of pump 8 flows into chamber 2 via line 6 in at least one direction. However, with valve 34 closed, chamber 2 does not flow directly into reservoir 14 via line 20, and with valve 35 closed, chamber 2 does not flow directly into reservoir 14 via line 21. When bidirectional motor 10 rotates in the first direction, piston 4 moves to the right to extend rod 5, causing bidirectional pump 8 (i.e., driven gear 55) to rotate in direction 45 and draw fluid from lines 22 and 7 through port 8b. In this embodiment, such fluid is drawn from chamber 3 and from reservoir 14 via line 7. One function of this configuration is to address the volume difference between opposing chambers 2 and 3. As piston 4 moves to the right within hydraulic cylinder 9, the volume of fluid discharged from the contracting right chamber 3 is less than the volume of fluid required to supply the expanding left chamber 2 without reservoir tank 14 and line 7. The bidirectional pump 8 outputs fluid to line 6 via port 8a. Fluid in line 6 flows into chamber 2, creating a pressure differential on piston 4 between chambers 2 and 3. This pressure differential is positive when the pressure on piston 4 in chamber 2 is greater than the relative pressure on piston 4 in chamber 3. If the pressure on piston 4 in chamber 2 is less than the pressure on piston 4 in chamber 3, the pressure differential will be negative. In this embodiment, since chamber 3 is always connected to reservoir 14, the pressure differential is always zero or positive. When this positive pressure differential, in this case the pressure in the left chamber 2 on piston 4, is large enough to overcome the opposing spring force of spring 36, this pressure causes rod 5 to extend to the right. Since chamber 3 is always connected to reservoir 14, when the piston force exceeds the opposite spring force of spring 36, piston 4 moves to the right and extends rod 5, thereby compressing spring 36 and opening safety valve 91.

[0075] like Figure 7As shown, to keep safety valve assembly 91 in the open state, valve 34 is energized, thus blocking the port of valve 34, and valve 35 is energized, thus blocking the port of valve 35. In these valve states, fluid flowing from left chamber 2 to tank 14 via lines 6 and 20, and lines 6 and 21, respectively, is blocked. In this embodiment, line 6 includes a check valve 24 between port 8a of pump 8 and line 20, which allows fluid to flow from port 8a of pump 8 to chamber 2, but prevents fluid from flowing from chamber 2 to line 22 and back to port 8a of pump 8. The position of valve 24 prevents it from blocking flow from chamber 2 to line 20 or line 21. Thus, this configuration maintains pressure in left chamber 2 such that spring 36 remains compressed, piston 4 and rod 5 cannot retract, and safety valve assembly 91 remains open. The hydraulic pressure acting on piston 4 is opposite to and at least equal to the spring force of spring 36. This pressure is maintained independently of the motor 10 and the pump 8 via valve 24. Alternatively, valve 24 can be removed and the motor 10 can be energized, thereby blocking the flow from chamber 2 to reservoir 14 via line 22 to keep valve assembly 91 open.

[0076] like Figure 8 As shown, both valves 34 and 35 are de-energized to retract rod 5 and close valve 91. When valve 34 is de-energized, the spring of solenoid valve 34 returns it to the open position. In this open state, chamber 2 is flow-connected to tank 14 via lines 6 and 20. When valve 35 is de-energized, the spring of solenoid valve 35 returns it to the open position. In this open state, chamber 2 is flow-connected to tank 14 via lines 6 and 21. The collar 60 is biased by spring 36 to retract rod 5 and move piston 4 to the left, closing valve assembly 91. When the pressure acting on piston 4 in left chamber 2 drops below the opposing spring force of spring 36, this spring force causes piston 4 to move to the left, and fluid flows from chamber 2 through open lines 20 and 21 to tank 14 and chamber 3. In this embodiment, such fluid flows into chamber 3 via line 7 and also into reservoir 14. This configuration addresses the volume difference between opposing chambers 2 and 3. When piston 4 moves to the left within hydraulic cylinder 9, the volume of fluid discharged from the contracting left chamber 2 is greater than the volume of fluid required to supply the expanding right chamber 3 without the storage tank 14 and pipeline 7.

[0077] The system in this embodiment provides at least two fault-redundant hydraulic paths for shutting down valve assembly 91 in the event of an error or malfunction. First, as Figure 9As shown, in the event of a flow restriction or blockage failure in motor 10, pump 8, and / or valve 34, valve 35 can be de-energized, even in the event of an emergency power failure, and the spring of solenoid valve 35 will subsequently return valve 35 to the open position. In this state, chamber 2 is flow-connected to line 7 via line 21, as well as to right chamber 3 and reservoir 14, thereby equalizing the pressure in chambers 2 and 3. The spring force of spring 36 acts to retract rod 5 and move piston 4 to the left. The resulting pressurized fluid from chamber 2 flows into chamber 3 via lines 6, 21, and 7 and also into reservoir 14. This configuration resolves the volume difference between the opposing chambers 2 and 3. When piston 4 moves to the left within hydraulic cylinder 9, the volume of fluid discharged from the contracting left chamber 2 is greater than the volume of fluid required to supply the expanding right chamber 2 without reservoir 14 and line 7. When the pressure in the left chamber 2 of piston 4 is lower than the opposing spring force of spring 36, this spring force causes piston 4 to move to the left, retracting rod 5 and closing safety valve 91. This valve closure of valve 91 does not require operation of electric motor 10, pump 8 and / or valve 34, and therefore can be provided even in the event of flow restriction or blockage failure in electric motor 10, pump 8 and / or valve 34.

[0078] Secondly, such as Figure 10 As shown, if the motor 10, pump 8, and / or valve 35 experience flow restriction or blockage, even in the event of an emergency power outage, valve 34 can be de-energized, and the spring of solenoid valve 34 will return valve 34 to the open position. In this state, chamber 2 is flow-connected to pipeline 7, right chamber 3, and reservoir 14 via pipeline 20, thereby equalizing the pressure in chambers 2 and 3. The spring force of spring 36 acts to retract rod 5 and move piston 4 to the left. The resulting pressurized fluid from chamber 2 flows into chamber 3 via pipelines 6, 20, and 7 and also into reservoir 14. This configuration resolves the volume difference between the opposing chambers 2 and 3. When piston 4 moves to the left within hydraulic cylinder 9, the volume of fluid discharged from the contracting left chamber 2 is greater than the volume of fluid required to supply the expanding right chamber 2 without reservoir 14 and pipeline 7. When the pressure in the left chamber 2 of piston 4 is lower than the opposing spring force of spring 36, this spring force causes piston 4 to move to the left, retracting rod 5 and closing safety valve 91. This valve closure of valve 91 does not require operation of electric motor 10, pump 8, or valve 35, and therefore can be provided even in the event of flow restriction or blockage failure in electric motor 10, pump 8, and / or valve 35.

[0079] The hydraulic manifold 193 and piston assembly 192 of the second embodiment are as follows: Figure 11As shown, the hydraulic manifold 193 typically has the same construction as hydraulic manifold embodiment 93 and typically includes a solenoid valve 34, a solenoid 35, and multiple hydraulic lines 6, 107, 20, 21, and 22. However, the piston assembly 192 in this embodiment contains only a single chamber in the closed fluid system. As shown, the piston assembly 192 does not include a second chamber 3, and only chamber 2 exists in the closed fluid system having a tank 14, valves 34 and 35, and hydraulic flow lines 6, 107, 20, 21, and 22.

[0080] like Figure 11 As shown, in hydraulic manifold embodiment 193, pump 8 is located in fluid line 22. One side or port 8a of pump 8 is connected to a single chamber 2 via fluid lines 22 and 6, while the opposite side or port 8b of pump 8 is connected to tank 14 only via fluid lines 22 and 107. Bypass fluid line 20 connects lines 6 and 107, and thus connects chamber 2 to tank 14. Solenoid valve 34 is disposed in line 20. Bypass fluid line 20 and solenoid valve 34 are disposed in line 6 between side 8a of pump 8 and left chamber 2, thus providing a first fluid line between chamber 2 and tank 14 that bypasses pump 8 and is independent of pump 8. Bypass fluid line 21 also connects lines 6 and 107, and thus also connects chamber 2 to tank 14. Solenoid valve 35 is disposed in line 21. A bypass fluid line 21 and a solenoid valve 35 are disposed in line 6 between side 8a of pump 8 and chamber 2, thus providing a second fluid line between chamber 2 and storage tank 14, bypassing and independent of pump 8. Therefore, line 22 having pump 8, line 20 having valve 34, and line 21 having valve 35 form a parallel hydraulic flow connection between chamber 2 and tank 14. Therefore, solenoid valve 34 and fluid line 20 are operably configured to provide a first hydraulic release path between chamber 2 and storage tank 14. Solenoid valve 35 and fluid line 21 are operably configured to provide a second hydraulic release path between chamber 2 and storage tank 14. Furthermore, if desired, fluid line 22 and pump 8 can be configured to operably provide a third hydraulic release path between chamber 2 and storage tank 14.

[0081] The system in this embodiment can be controlled in the same manner as in the first embodiment 93 described above, to provide at least two operating states and two fail-safe states. For example... Figure 11As shown, to extend rod 5 and open safety valve assembly 91, valve 34 is energized such that valve 35 is in a blocked port and closed state, and valve 35 is energized such that valve 35 is in a blocked port and closed state. Therefore, side 8a of pump 8 is connected to chamber 2 via line 6 in at least one direction, while chamber 2 is not connected to reservoir 14 via lines 20 or 21. When bidirectional motor 10 rotates in the first direction, piston 4 moves to the right to extend rod 5, causing bidirectional pump 8 (i.e., driven gear 55) to rotate in direction 45 and draw fluid from lines 22 and 107 through port 8b. In this embodiment, this fluid is drawn from reservoir 14 only via line 107. Bidirectional pump 8 outputs fluid to line 6 through port 8a. Fluid in line 6 flows into chamber 2, thereby applying pressure to piston 4. When the pressure in the single chamber 2 on piston 4 becomes sufficient to overcome the opposing spring force of spring 36, this pressure causes rod 5 to extend to the right. When the piston force exceeds the opposing spring force of spring 36, piston 4 moves to the right and rod 5 extends, thereby compressing spring 36 and opening safety valve 91. Similar to embodiment 93, this configuration can also be used to maintain pressure in the left chamber 2 such that spring 36 remains compressed, piston 4 and rod 5 cannot retract, and safety valve assembly 91 remains open. The hydraulic pressure on piston 4 is maintained opposite to and at least equal to the spring force of spring 36. This pressure is maintained independently of motor 10 and pump 8 via valve 24.

[0082] Similar to Embodiment 93, if one of the motor 10, pump 8, and / or valve 34 or 35 experiences a flow restriction or blockage failure, the other of valve 34 or 35 can be de-energized, and even in the event of an emergency power failure, the spring of the solenoid valve will return the solenoid valve to the open position. In these failure states, chamber 2 is flow-connected to line 107 via line 20 or line 21, but the single chamber 2 is not connected to the second chamber. The spring force of spring 36 still applies to retract rod 5 and move piston 4 to the left. The resulting pressurized fluid from the single chamber 2 flows into reservoir 14 via lines 6, 107, and valve 34 or 35, and this configuration does not require addressing any volume differences between the relative chambers as in Embodiment 92. When the pressure in the left chamber 2 on piston 4 is lower than the opposing spring force of spring 36, this spring force moves piston 4 to the left, retracts rod 5, and closes safety valve 91. This valve closure of valve 91 does not require operation of electric motor 10, pump 8, or valve 34 or 35, and therefore can be provided even in the event of flow restriction or blockage failure in electric motor 10, pump 8, and / or valve 34 or 35.

[0083] The hydraulic manifold 293 of the third embodiment is as follows: Figure 12-16As shown in the figure, the hydraulic manifold 293 typically includes a solenoid valve 234, a solenoid 35, and multiple hydraulic lines 206, 7, 21, and 22. The pump 8, chamber 2, chamber 3, tank 14, valves 234 and 35, and hydraulic flow lines 206, 7, 21, and 22 form a closed fluid system.

[0084] like Figure 12-16 As shown, in this hydraulic manifold embodiment 293, pump 8 is located in fluid line 22. One side or port 8a of pump 8 is connected to the left chamber 2 via fluid lines 22 and 206, and the opposite side or port 8b of pump 8 is connected to the right chamber 3 via fluid lines 22 and 7. Port 8b of pump 8 is also connected to tank 14 via fluid lines 22 and 7. Right chamber 3 is connected to tank 14 via fluid line 7. Solenoid valve 234 is disposed in line 206 between pump 8 and chamber 2. Fluid lines 22, pump 8, and valve 234 connect lines 206 and 7, and thus connect chamber 2 to tank 14 and chamber 3. Fluid lines 22, pump 8, and valve 234 provide a first fluid line between chamber 2 and storage tank 14. Such a flow line is not bypassed and is not independent of pump 8.

[0085] A bypass fluid line 21 also connects lines 206 and 7, thus connecting chamber 2 to tank 14 and chamber 3. A solenoid valve 35 is disposed in line 21. The bypass fluid line 21 and solenoid valve 35 are disposed in line 206 between side 8a of pump 8 and left chamber 2, thus providing a second fluid line between chamber 2 and storage tank 14, bypassing pump 8 and valve 234 and independent of pump 8 and valve 234. Therefore, line 22, in which pump 8 and valve 234 are located, and line 21, in which valve 35 is located, form a parallel hydraulic flow connection between chamber 2 and tank 14. Therefore, solenoid valve 234, pump 8, and fluid line 22 are operably configured to provide a first hydraulic release path between chamber 2 and storage tank 14. Solenoid valve 35 and fluid line 21 are operably configured to provide a second hydraulic release path between chamber 2 and storage tank 14.

[0086] The system in this embodiment can be controlled in at least two operating states and at least two fail-safe states. For example... Figure 12As shown, valve 234 is de-energized to extend rod 5 and open safety valve assembly 91. When valve 234 is de-energized, the spring of solenoid valve 234 returns it to the open position. In this open state, chamber 2 is flow-connected to side 8a of pump 8 via line 206. However, valve 35 is energized, thus blocking the port and closing valve 35. With valve 35 closed, chamber 2 is not flow-connected directly to reservoir 14 via line 21. When bidirectional motor 10 rotates in the first direction, piston 4 moves to the right to extend rod 5, causing bidirectional pump 8 (i.e., driven gear 55) to rotate in direction 45 and draw fluid from lines 22 and 7 through port 8b. In this embodiment, such fluid is drawn from chamber 3 and from reservoir 14 via line 7. One function of this configuration is to address the volume difference between opposing chambers 2 and 3. As piston 4 moves to the right within hydraulic cylinder 9, the volume of fluid discharged from the contracting right chamber 3 is less than the volume of fluid required to supply the expanding left chamber 2 without reservoir tank 14 and line 7. The bidirectional pump 8 outputs fluid through port 8a to line 206. Fluid in line 206 flows into chamber 2, creating a pressure differential on piston 4 between chambers 2 and 3. This pressure differential is positive when the pressure on piston 4 in chamber 2 is greater than the relative pressure on piston 4 in chamber 3. When this positive pressure differential, in this case the pressure in the left chamber 2 on piston 4, is large enough to overcome the opposing spring force of spring 36, this pressure causes rod 5 to extend to the right. Since chamber 3 is always connected to reservoir 14, when this piston force exceeds the opposing spring force of spring 36, piston 4 moves to the right and rod 5 extends, thereby compressing spring 36 and opening safety valve 91.

[0087] like Figure 13 As shown, to keep safety valve assembly 91 in the open state, valve 34 is energized, thus blocking its port; valve 35 is energized, thus blocking its port. In these valve states, the fluid flowing from left chamber 2 through lines 206 and 21 to pump 8 and tank 14 is blocked, thereby maintaining pressure in left chamber 2, keeping spring 36 compressed, preventing piston 4 and rod 5 from retracting, and keeping safety valve assembly 91 open. The hydraulic pressure acting on piston 4 is opposite to and at least equal to the spring force of spring 36. This pressure is maintained independently of motor 10 and pump 8 via valve 234.

[0088] To retract lever 5 and close valve assembly 91 in a rate-controlled manner, valve 234 is de-energized. When valve 234 is de-energized, the spring of solenoid valve 234 returns it to the open position. In this open state, chamber 2 flows through lines 206 and 22 to port 8a of pump 8. However, valve 35 is energized, thus blocking the port, so chamber 2 does not flow directly through line 21 to reservoir 14 and chamber 3. The spring force of spring 36 acts to retract lever 5 and move piston 4 to the left. When bidirectional motor 10 rotates in the second direction, piston 4 moves to the left to retract lever 5, thereby rotating bidirectional pump 8 in direction 46 and allowing fluid to flow from line 206 and chamber 2 through port 8a. Bidirectional pump 8 also outputs fluid from port 8b to line 7. In this embodiment, such fluid flows through line 7 into chamber 3 and also into reservoir 14. This configuration addresses the volume difference between opposing chambers 2 and 3. Therefore, the motor 10 and pump 8 can be used to measure the fluid flow from the left chamber 2, thereby measuring the rate at which the safety valve assembly 91 closes.

[0089] like Figure 14 As shown, both valves 234 and 35 can be de-energized to retract rod 5 and close valve 91. When valve 234 is de-energized, the spring of solenoid valve 234 returns it to the open position. In this open state, chamber 2 is flow-connected to tank 14 via line 22 and pump 8. When valve 35 is de-energized, the spring of solenoid valve 35 returns it to the open position. In this open state, chamber 2 is flow-connected to tank 14 via line 21. Collar 60 is biased by spring 36 to retract rod 5 and move piston 4 to the left, closing valve assembly 91. When the pressure acting on piston 4 in left chamber 2 is lower than the opposing spring force of spring 36, this spring force causes piston 4 to move to the left, and fluid flows from chamber 2 through the open pump 8 and open lines 22 and 21 to tank 14 and chamber 3. In this embodiment, such fluid flows into chamber 3 via line 7 and also into reservoir 14. This configuration addresses the volume difference between opposing chambers 2 and 3.

[0090] The system in this embodiment provides at least two fault-redundant hydraulic paths for shutting down valve assembly 91 in the event of an error or malfunction. First, as Figure 15As shown, in the event of a flow restriction or blockage failure in motor 10, pump 8, and / or valve 234, valve 35 can be de-energized, even in the event of an emergency power failure, and the spring of solenoid valve 35 will subsequently return valve 35 to the open position. In this state, chamber 2 is flow-connected to line 7 via line 21, as well as to right chamber 3 and reservoir 14, thereby equalizing the pressure in chambers 2 and 3. The spring force of spring 36 acts to retract rod 5 and move piston 4 to the left. The resulting pressurized fluid from chamber 2 flows into chamber 3 via lines 206, 21, and 7 and also into reservoir 14. This configuration resolves the volume difference between the opposing chambers 2 and 3. When the pressure in left chamber 2 on piston 4 is lower than the opposing spring force of spring 36, this spring force causes piston 4 to move to the left, retracting rod 5 and closing safety valve assembly 91. This valve closure of valve 91 does not require operation of electric motor 10, pump 8 and / or valve 234, and therefore can be provided even in the event of flow restriction or blockage failure in electric motor 10, pump 8 and / or valve 234.

[0091] Secondly, such as Figure 16 As shown, if valve 35 experiences a flow restriction or blockage, valve 234 can be de-energized even in an emergency power outage, and the spring of solenoid valve 234 will return valve 234 to the open position. In this state, chamber 2 is connected to port 8a of pump 8 via line 206. Even if valve 35 fails and does not open, and even if motor 10 and pump 8 fail but do not open, gears 55 and 56 can rotate freely, allowing hydraulic fluid to flow from port 8a to port 8b. Chamber 2 is also connected to right chamber 3 and reservoir 14 via line 206, pump 8, and lines 22 and 7, allowing equal pressure in chambers 2 and 3. The spring force of spring 36 retracts rod 5 and moves piston 4 to the left. The resulting pressurized fluid from chamber 2 flows into chamber 3 via line 6, pump 8, and lines 22 and 7, and also into reservoir 14. This configuration resolves the volume difference between the opposing chambers 2 and 3. When the pressure in the left chamber 2 of piston 4 is lower than the opposing spring force of spring 36, this spring force causes piston 4 to move to the left, retracting rod 5 and closing safety valve assembly 91. This valve closure of valve assembly 91 does not require operation of valve 35, and therefore can be provided even in the event of flow restriction or blockage failure in valve 35.

[0092] The hydraulic manifold 393 of the fourth embodiment is as follows Figure 17 As shown, hydraulic manifold 393 typically has the same construction as hydraulic manifold embodiment 293 and generally includes solenoid valve 234, solenoid 35, and multiple hydraulic lines 206, 107, 21, and 22. However, the piston assembly in this embodiment is different from... Figure 11The piston assembly 192 shown is identical and contains only a single chamber in a closed fluid system. As shown, piston assembly 192 does not include a second chamber 3, and only chamber 2 exists in the closed fluid system having tank 14, valve 234, valve 35, and hydraulic flow lines 206, 107, 21, and 22.

[0093] like Figure 17 As shown, in hydraulic manifold embodiment 393, pump 8 is located in fluid line 22. One side or port 8a of pump 8 is connected to a single chamber 2 via fluid line 22, pump 8, and fluid line 206, while the opposite side or port 8b of pump 8 is connected to tank 14 only via fluid lines 22 and 107. Line 206, solenoid valve 234, pump 8, and lines 22 and 107 provide a first fluid line between chamber 2 and storage tank 14, which is not bypassed and is not independent of pump 8. Bypass fluid line 21 and solenoid valve 35 are provided in line 6 between side 8a of pump 8 and chamber 2, and thus provide a second fluid line between chamber 2 and storage tank 14, which is bypassed and independent of pump 8 and valve 234. Therefore, line 22, in which pump 8 and valve 234 are located, and line 21, in which valve 35 is located, form a parallel hydraulic flow connection between chamber 2 and tank 14. Therefore, solenoid valve 234, pump 8, and fluid line 22 are operably configured to provide a first hydraulic release path between chamber 2 and storage tank 14. Solenoid valve 35 and fluid line 21 are operably configured to provide a second hydraulic release path between chamber 2 and storage tank 14.

[0094] The system in this embodiment can be controlled in the same manner as in embodiment 293 described above to provide at least two operating states and two fail-safe states. To extend lever 5 and open safety valve assembly 91, valve 234 is de-energized, thus valve 35 is in the open state, while valve 35 is energized, thus valve 35 is in the blocked port and closed state. Therefore, side 8a of pump 8 is flowably connected to chamber 2 in at least one direction via valve 234. Chamber 2 is not flowably connected to reservoir 14 via line 21. Only side 8b of pump 8 is flowably connected to reservoir 14. When bidirectional motor 10 rotates in the first direction, piston 4 moves to the right to extend lever 5, causing bidirectional pump 8 (i.e., driven gear 55) to rotate in direction 45 and draw fluid flow from lines 22 and 107 and reservoir 14 via port 8b. In this embodiment, this fluid is drawn from reservoir 14 only via line 107. Bidirectional pump 8 outputs fluid through port 8a to line 206 and through the open valve 234. Fluid in line 206 flows into chamber 2, thereby applying positive pressure to piston 4. When the pressure in chamber 2 on piston 4 becomes large enough to overcome the opposing spring force of spring 36, this pressure causes rod 5 to extend to the right. When this piston force exceeds the opposing spring force of spring 36, piston 4 moves to the right and extends rod 5, thereby compressing spring 36 and opening safety valve 91.

[0095] like Figure 17 As shown, to keep safety valve assembly 91 in the open state, valve 34 is energized, thus valve 234 is in the blocked port state, and valve 35 is energized, thus valve 35 is in the blocked port state. In these valve states, the fluid flow from left chamber 2 to pump 8 and tank 14 via lines 206 and 21 is blocked, thereby maintaining pressure in left chamber 2, keeping spring 36 compressed, preventing piston 4 and rod 5 from retracting, and keeping safety valve assembly 91 open. The hydraulic pressure acting on piston 4 is opposite to and at least equal to the spring force of spring 36. This pressure is maintained independently of motor 10 and pump 8 via valve 234.

[0096] Similar to Embodiment 293, if one of valves 234 or 35 experiences a flow restriction or blockage, the other of valves 234 or 35 can be de-energized, and even in the event of an emergency power failure, the spring of the relevant solenoid valve will return the relevant valve to the open position. In these fault states, chamber 2 is flow-connected to line 107 and tank 14 via pump 8 and line 22 or via line 21 (whichever is appropriate), and chamber 2 is not connected to the second chamber. The spring force of spring 36 still applies to retract rod 5 and move piston 4 to the left. The resulting pressurized fluid from single chamber 2 flows into reservoir 14 via line 206, valve 234, line 22, and line 107, or via line 206, valve 35, line 21, and line 107. This configuration does not require addressing any volumetric differences between the relative chambers as in Embodiment 92. When the pressure in the left chamber 2 of piston 4 is lower than the opposing spring force of spring 36, this spring force causes piston 4 to move to the left, retract rod 5, and close safety valve assembly 91.

[0097] Since this configuration does not require addressing any volume differences between relative chambers, the system in this embodiment can also be controlled to provide at least a third operating state. To selectively retract lever 5 at a variable or controlled rate, or to position safety valve 91 between its open and closed positions, valve 234 is de-energized, causing valve 35 to be in an open state, while valve 35 is energized, causing valve 35 to be in a blocked port and closed state. Therefore, side 8a of pump 8 is flowably connected to chamber 2 via valve 234 in at least one direction. Chamber 2 is not flowably connected to reservoir 14 via line 21. Only side 8b of pump 8 is flowably connected to reservoir 14. When bidirectional motor 10 rotates in the second direction, piston 4 moves to the left to retract lever 5, thereby rotating bidirectional pump 8 in direction 46 and drawing fluid from line 206 and chamber 2 through port 8a. In this embodiment, this fluid is drawn only from chamber 2. Bidirectional pump 8 outputs fluid through port 8b to line 107, and only to reservoir 14 when valve 35 is closed. When the pressure in the single chamber 2 on piston 4 is lower than the opposing spring force of spring 36, piston 4 will move to the left, retract rod 5, and begin to close safety valve assembly 91. When the desired position between its open and closed positions is reached, valve 234 can be energized and closed to maintain that position if necessary. Therefore, motor 10 and pump 8 can be used to variably control the pressure in chamber 2 and the flow rate of fluid entering and leaving chamber 2, thereby controlling the rate at which safety valve assembly 91 opens or closes and the position of safety valve assembly 91 in either direction.

[0098] The hydraulic piston assembly 493 of the fifth embodiment is as follows: Figure 18 As shown. This embodiment is similar to Figure 13The embodiment shown features a dual-rod equal-area piston assembly 493. As shown, piston 404 includes opposing rods 405a and 405b mounted on piston 404 for movement with piston 404. Rod 405b extends to the right and passes through the right end wall 409b of housing 409. Rod 405a extends to the left and penetrates the left end wall 409a of housing 409. In this embodiment, due to the addition of rod 405a passing through chamber 2, the left-facing annular vertical end face 404a of piston 404 faces the left chamber 2, and due to rod 405b extending through chamber 3 and housing 409, the right-facing annular vertical end face 404b of piston 404 faces the right chamber 3. With rods 405a and 405b having equal diameters, this results in an equal piston area configuration, where the surface area of ​​face 404a is substantially the same as the surface area of ​​face 404b. In this embodiment, rod 405b is connected to collar 60 of safety valve assembly 91.

[0099] Safety valve 91 may include sensors 40a and 40b for position monitoring of actuator rod 5 and sleeve collar 60; compensator 13 may include sensor 153 for position monitoring of compensator piston 15; valve 34 may include sensor 43 for position monitoring of valve 34; valve 35 may include sensor 44 for position monitoring of valve 35; and hydraulic system 93 may include pressure sensor 41 for pressure monitoring of hydraulic system 93. Such sensors can be used to provide in-well diagnostics in underground safety valve 90 via controller 74. Controller 74 is a digital device with output lines that are logic functions of its input lines; examples include microprocessors, microcontrollers, field-programmable gate arrays, programmable logic devices, application-specific integrated circuits, or other similar devices. Controller 74 is configured to perform various computer-implemented functions, such as performing method steps and calculations, and storing relevant data as disclosed herein. For communication with various sensors, sensor interface 73 allows signals transmitted from sensors to be converted into signals that processor 74 can understand and process. Sensors can be coupled to sensor interface 73 via wired connections. In other embodiments, they can be coupled to sensor interface 73 via wireless connections. Diagnostic monitoring of the underground safety valve 90 can be implemented in the controller 74. Programming can be implemented in any form of computer-readable medium or a dedicated computer or data processor programmed, configured, or constructed to execute object instructions. Therefore, the in-well electronics 95 includes a processor, a non-transitory computer-readable medium, and processor-executable code stored on the non-transitory computer-readable medium. The processor can be implemented as a single processor or multiple processors that work together or independently to execute the processor-executable code described herein. Some examples of processors are microprocessors, microcontrollers, central processing units (CPUs), peripheral interface controllers (PICs), programmable logic controllers (PLCs), microcomputers, digital signal processors (DSPs), programmable logic devices (“PLDs”), multi-core processors, field-programmable gate arrays (FPGAs), and combinations thereof. The terms computer or processor as used herein refer to any of the above-mentioned devices as well as any other data processor. Computer-readable media include media configured to store or transmit computer-readable code, or media in which computer-readable code can be embedded. Non-transitory computer-readable media can be implemented in any suitable manner, such as via random access memory (RAM), read-only memory (ROM), hard disk drive, hard disk drive array, solid-state drive, storage device, magnetic drive, flash drive, flash memory, memory card, optical drive, or other similar device or medium. A non-transitory computer-readable medium can be a single non-transitory computer-readable medium or multiple non-transitory computer-readable media that function logically together or independently. The computer system described herein is for illustrative purposes only.The described embodiments and methods can be implemented in any type of computer system or programming or processing environment. Furthermore, it means including processing performed in a distributed computing environment if the task or module is performed by more than one processing device. Those skilled in the art will recognize that any computer system with appropriate programming means will be able to execute the steps of the disclosed methods embodied in the program product. Those skilled in the art will also recognize that although some exemplary embodiments described in this specification are geared towards software installed and executed on computer hardware, alternative embodiments implemented as firmware or hardware are fully within the scope of this disclosure.

[0100] Therefore, system 90 includes diagnostic commands from controller 74 and feedback to controller 74. Figure 21 This is a flowchart of an example method 210 for performing diagnostics on the hydraulic piston assembly 92, implemented in the controller 74 and the diagnostic module 75. Method 210 can be embodied in computer-readable code on a computer-readable medium, such that when the processor of the controller 74 executes the computer-readable code, the processor executes method 210. Method 210 is therefore implemented as code stored on a non-transitory computer-readable medium of the controller 74, and the controller 74 executes such processor-executable code. Reference Figure 21 In step 211 of diagnostic function 210, a start signal is generated to activate the various steps of method 210 and object instructions stored on a non-transitory computer-readable medium on controller 74. In step 212, controller 74 commands system 90 to fully retract actuator rod 5 and sleeve collar 60, and refers to... Figure 5 This moves the sleeve collar 60 to the left and to the desired position. Figure 8 The position is shown. In blocks 213 and 214, controller 74 monitors sensor 40a for a defined period of time after commanding system 90 to the fully retracted position. In block 213, controller 74 determines whether sleeve collar 60 has triggered proximity switch 40a, which indicates that the actuator rod is in the position shown. Figure 8The fully retracted position is shown. In block 214, the controller 74 determines whether a threshold time period has been exceeded if the sleeve collar 60 has not triggered the proximity switch 40a. In this embodiment, such a threshold time period is five minutes, but an alternative time threshold can be used as needed. If the position sensor 40a is not activated within the stored time threshold after command 212, the controller 74 generates an "error" signal or report in step 222, and in step 223, the controller 74 commands the motor driver 71 to enter a "disabled" state by turning off the output power at the motor driver 71, allowing the motor 10 to rotate freely. On the other hand, if the sleeve collar 60 triggers the sensor 40a within the stored time threshold, indicating that the actuator rod 5 and the sleeve collar 60 are in the commanded fully retracted position, then in step 215, the controller 74 commands the system 90 to fully extend the actuator rod 5 and the sleeve collar 60, and refers to... Figure 5 This moves the sleeve collar 60 to the right and to the position where it is located. Figure 6 The position is shown. In step 216, the controller 74 monitors the state changes of the position sensor 40b. In blocks 217 and 218, the controller 74 monitors the sensor 40b for a defined period of time after commanding the system 90 to the fully extended position. In block 217, the controller 74 determines whether the sleeve collar 60 has triggered the proximity switch 40b, which indicates that the actuator rod is in the position shown. Figure 6The fully extended position is shown. In block 218, controller 74 determines whether a threshold time period has been exceeded if the sleeve collar 60 has not triggered the proximity switch 40b. In this embodiment, such a threshold time period is five minutes, but alternative time thresholds may be used as needed. If, after command 215, the position sensor 40b is not activated within the stored time threshold, controller 74 generates an “error” signal or report in step 219, and in step 221, controller 74 commands motor driver 71 to enter a “disabled” state. On the other hand, if the sleeve collar 60 triggers sensor 40b within the stored time threshold, indicating that actuator rod 5 and sleeve collar 60 are in the commanded fully extended position, in step 220, controller 74 generates an operation signal or report, and hydraulic piston assembly 92 is diagnosed as fully operational. Controller 74 thus provides a built-in in-well hydraulic piston assembly 92 diagnostic program that can run at selected and automatic periodic intervals. If the movement of the safety valve is not detected within a given time threshold by sensor 40a (for a full retraction command) or sensor 40b (for a full extension command), the controller 74 provides an error signal. The controller 74 may also provide a valve closing command, and a "disable" command may include de-energizing solenoids 34 and 35 to place the safety valve 90 in a fail-safe closed position. The error signal may be sent to the surface controller 11 on platform 100, and if no error is detected, the controller 74 may send an acknowledgment signal to the surface controller 11 on platform 100. Although the time threshold is greater than five minutes in this embodiment, other time thresholds may be used depending on the desired operating parameters of the system.

[0101] The controller 74 also includes a compensator diagnostic function or procedure 300 in the diagnostic module 75 for determining whether the compensation storage component 13 is operable. Figure 22 This is a flowchart of an example method 300 for performing diagnostics on the compensated reservoir component 13, implemented in the controller 74 and the diagnostic module 75. Method 300 can be embodied in computer-readable code on a computer-readable medium, such that when the processor of the controller 74 executes the computer-readable code, the processor executes method 300. Method 300 is therefore implemented as code stored on a non-transitory computer-readable medium of the controller 74, and the controller 74 executes such processor-executable code. Reference Figure 22 In step 301 of diagnostic function 300, a start signal is generated to activate the various steps of method 300 and object instructions stored on a non-transitory computer-readable medium of controller 74. In step 302, controller 74 commands system 90 to fully retract actuator rod 5 and sleeve collar 60, and refers to... Figure 5 This moves the sleeve collar 60 to the left and to the desired position. Figure 8The position is shown. In blocks 303 and 304, controller 74 monitors sensor 40a for a defined period of time after commanding system 90 to the fully retracted position. In block 303, controller 74 determines whether sleeve collar 60 has triggered proximity switch 40a, which indicates that the actuator rod is in the position shown. Figure 8 The fully retracted position is shown. In block 304, controller 74 determines whether a threshold time period has been exceeded if sleeve collar 60 has not triggered proximity switch 40a. In this embodiment, such a threshold time period is five minutes, but alternative time thresholds may be used as needed. If position sensor 40a is not activated within the stored time threshold after command 302, controller 74 generates an "error" signal or report in step 312, and in step 313, controller 74 commands motor driver 71 to enter a "disabled" state. On the other hand, if sleeve collar 60 triggers sensor 40a within the stored time threshold, indicating that actuator rod 5 and sleeve collar 60 are in the commanded fully retracted position, in step 305, controller 74 commands system 90 to fully extend actuator rod 5 and sleeve collar 60, and refers to... Figure 5 This moves the sleeve collar 60 to the right and to the position where it is located. Figure 6 The position is shown. In step 306, the controller 74 monitors the state changes of the compensator position sensor 153. In blocks 314, 307, and 308, the controller 74 monitors sensors 153 and 40b for a defined period of time after commanding system 90 to the fully extended position. In block 314, the state changes of sensor 153 are monitored to indicate the movement of the compensator piston 15. Because spring 36 is biased to increase the pressure in the closed hydraulic system 93 relative to the pressure outside the closed hydraulic system 93, the compensator piston 15 will move to compensate for this pressure difference when actuator piston 4 extends. This movement is monitored by the controller 74 via position sensor 153. If position sensor 153 indicates a change in the position of compensator piston 15 in block 314, the controller 74 generates an operation signal or report in step 315, and the compensated storage assembly 13 is diagnosed as fully operational. On the other hand, if the position sensor does not detect a change in the position of the compensator piston 15 in block 314, then in block 307, the controller 74 determines whether the sleeve collar 60 has triggered the proximity switch 40b, which will indicate that the actuator rod is in the correct position. Figure 6The fully extended position is shown. In block 308, controller 74 determines whether a threshold time period has been exceeded without sensing a position change in compensator piston 15 or sleeve ring 60 triggering proximity switch 40b. In this embodiment, such a threshold time period is five minutes, but alternative time thresholds can be used as needed. If, after command 305, neither position sensor 153 nor position sensor 40b is activated within the stored time threshold, controller 74 generates an "error" signal or report in step 309, and in step 311, controller 74 commands motor driver 71 to enter a "disabled" state. On the other hand, if sleeve ring 60 triggers sensor 40b within the stored time threshold, indicating that actuator rod 5 and sleeve ring 60 are in the commanded fully extended position, but sensor 153 does not detect a position change in compensator piston 15, in step 316, controller 74 generates an "error" signal indicating a fault in sensor 153 or compensator storage assembly 13, or controller 74 may generate a timeout to stop the process and indicate that the actuator is not responding as expected and requires alternative diagnostics. The controller 74 thus provides a built-in diagnostic program for the in-well compensation reservoir assembly 13, which can run at selected and automatic periodic intervals. The controller 74 can also provide valve closing commands, and the "disable" command can include de-energizing solenoids 34 and 35 to place safety valve 90 in the fail-safe closed position. An error signal can be sent to the surface controller 11 on platform 100, and if no error is detected, the controller 74 can send an acknowledgment signal to the surface controller 11 on platform 100. Although the time threshold is greater than five minutes in this embodiment, other time thresholds may be used depending on the desired operating parameters of the system.

[0102] The controller 74 also includes a solenoid valve diagnostic function or program 400 in the diagnostic module 75 for determining whether the solenoid valve 34 or solenoid valve 35 is operable. Figure 23 This is a flowchart of a first embodiment example method 400 for performing diagnostics on solenoid valves 34 and 35, implemented in controller 74 and diagnostic module 75. Method 400 can be embodied in computer-readable code on a computer-readable medium, such that when the processor of controller 74 executes the computer-readable code, the processor executes method 400. Method 400 is thus implemented as code stored on a non-transitory computer-readable medium of controller 74, and controller 74 executes such processor-executable code. In this embodiment, solenoid driver 72 includes solenoid sensor 76, and the resistance of the solenoid coil and the solenoid drive current of the target solenoid valve 34 or 35 are used to determine the state of the target solenoid valves 34, 35. Specifically, refer to... Figure 23In step 401 of the diagnostic function 400, a start signal is generated to activate the various steps of method 400 and the object instructions stored on a non-transitory computer-readable medium of the controller 74. In step 402, the controller 74 commands the electric motor driver 71 to enter a "disabled" state. In step 403, the controller 74 monitors the resistance of the solenoid coil of the object solenoid valve, and in step 404, the controller 74 estimates the solenoid coil temperature based on this resistance. In step 405, the controller 74 commands the object solenoid valve 34 or 35 to be in an "open" or energized state via the solenoid driver 72. In step 406, the controller 74 monitors the solenoid current. In step 407, the controller 74 commands the object solenoid valve 34 or 35 to be in a "closed" or de-energized state via the solenoid driver 72. If, in block 408, the current sensor 76 indicates a current within the established range based on a lookup table stored in the controller 74, then in step 410, the controller 74 generates an operation signal or report, and the target solenoid valve 34 or 35 is diagnosed as fully operational. Conversely, if, in block 408, the current sensor 76 indicates a current outside the established range based on a lookup table stored in the controller 74, then in step 409, the controller 74 generates an "error" or "out-of-range" signal or report indicating a fault in the target solenoid valve 34 or 35.

[0103] Figure 24 This is a flowchart of a second embodiment example method 400b for performing diagnostics on solenoid valves 34 and 35, implemented in controller 74 and diagnostic module 75. Method 400b can be embodied in computer-readable code on a computer-readable medium, such that when the processor of controller 74 executes the computer-readable code, the processor executes method 400b. Method 400b is therefore implemented as code stored on a non-transitory computer-readable medium of controller 74, and controller 74 executes such processor-executable code. In this embodiment, solenoid valve 34 includes a sensor 43 for position monitoring of valve 34, and solenoid valve 35 includes a sensor 44 for position monitoring of valve 35. (See reference...) Figure 24In step 401b of diagnostic function 400b, a start signal is generated to activate the various steps of method 400b and the object instructions stored on a non-transitory computer-readable medium of controller 74. In step 402b, controller 74 commands electric motor driver 71 to enter a "disabled" state. In step 406b, controller 74 monitors position sensor 43 or 44 (as applicable). In step 405b, controller 74 commands object solenoid valve 34 or 35 to be in an "open" or energized state via solenoid driver 72. In block 408b, controller 74 determines whether sensor 43 or 44 respectively indicates that the valve element of solenoid valve 34 or 35 is open as instructed. If sensor 43 or 44 indicates in block 408b that valve 34 or 35 is in the commanded open position, then in step 410b, controller 74 generates an operation signal or report, and object solenoid valve 34 or 35 is diagnosed as fully operational. On the other hand, if sensor 43 or 44 indicates in block 408b that valve 34 or 35 is not in the open position as instructed, then in step 409b, controller 74 generates an "error" or "out of range" signal or report indicating a fault in solenoid valve 34 or 35.

[0104] Figure 25 This is a flowchart of a third embodiment example method 400c for performing diagnostics on solenoid valves 34 and 35, implemented in controller 74 and diagnostic module 75. Method 400c can be embodied in computer-readable code on a computer-readable medium, such that when the processor of controller 74 executes the computer-readable code, the processor executes method 400c. Method 400c is therefore implemented as code stored on a non-transitory computer-readable medium of controller 74, and controller 74 executes such processor-executable code. In this embodiment, as... Figure 5 As shown, the solenoid valve 34 includes a pressure sensor 41 for pressure monitoring of the hydraulic system 93. (Reference) Figure 25 In step 401c of the diagnostic function 400c, a start signal is generated to activate the various steps of method 400c and the object instructions stored on the non-transitory computer-readable medium of the controller 74. In step 402c, the controller 74 commands the system 90 to fully retract the actuator rod 5 and the sleeve collar 60, and refers to... Figure 5 This moves the sleeve collar 60 to the left and to the desired position. Figure 8The positions are shown. In step 403c, the controller 74 commands the motor driver 71 and solenoid driver 72 to enter a "disabled" state by turning off the output power at the motor driver 71 to allow the motor 10 to rotate freely, and by turning off the output power at the solenoid driver 72 to de-energize and freely open solenoids 34 and 35 respectively. In step 404c, the controller 74 monitors the pressure sensor 41. In step 405c, the pump 8 is driven by the motor 10 at a predetermined test speed. In this embodiment, such a test speed is 1000 rpm, but an alternative test speed may be used as needed. In block 406c, the controller 74 determines whether the pressure sensor 41 indicates that a first threshold pressure has been exceeded. In this embodiment, such a first threshold pressure is 100 psi, but an alternative pressure threshold may be used as needed. If the pressure sensor 41 indicates a pressure greater than the first threshold pressure in block 406c, then in step 419c, the controller 74 generates an "error" or "out-of-range" signal or report indicating a malfunction in solenoid valves 34 and 35. On the other hand, if pressure sensor 41 indicates a pressure less than or equal to a first threshold pressure in block 406c, then in step 407c, controller 74 commands both solenoid valves 34 and 35 to enter an "open" or energized state via solenoid actuator 72. In block 408c, controller 74 determines whether pressure sensor 41 indicates that a second threshold pressure has been exceeded. In this embodiment, such a second threshold pressure is 500 psi, but an alternative pressure threshold may be used as needed. If pressure sensor 41 indicates a pressure less than the second threshold pressure in block 407c, then in step 419c, controller 74 generates an "error" or "out of range" signal or report indicating a malfunction in solenoid valves 34 and 35. On the other hand, if pressure sensor 41 indicates a pressure greater than or equal to the second threshold pressure in block 408c, then in step 409c, controller 74 commands solenoid valve 34 to enter a "closed" or de-energized state via solenoid actuator 72. In block 410c, controller 74 determines whether pressure sensor 41 indicates that a third threshold pressure has been exceeded. In this embodiment, the third threshold pressure is 100 psi, but an alternative pressure threshold can be used as needed. If pressure sensor 41 indicates a pressure greater than the third threshold pressure in block 410c, then in step 420c, controller 74 generates an "error" or "out of range" signal or report indicating a fault in solenoid valve 34. On the other hand, if pressure sensor 41 indicates a pressure less than or equal to the third threshold pressure in block 410c, then in step 411c, controller 74 commands both solenoid valves 34 and 35 to enter an "open" or energized state via solenoid actuator 72. In block 412c, controller 74 determines whether pressure sensor 41 indicates that a fourth threshold pressure has been exceeded.In this embodiment, the fourth threshold pressure is 500 psi, but an alternative pressure threshold may be used as needed. If pressure sensor 41 indicates a pressure less than the fourth threshold pressure in block 412c, then in step 420c, controller 74 generates an "error" or "out-of-range" signal or report indicating a malfunction in solenoid valve 34. On the other hand, if pressure sensor 41 indicates a pressure greater than or equal to the fourth threshold pressure in block 412c, then in step 413c, controller 74 commands solenoid valve 34 to be in a "closed" or de-energized state via solenoid actuator 72. In block 414c, controller 74 determines whether pressure sensor 41 indicates that a fifth threshold pressure has been exceeded. In this embodiment, the fifth threshold pressure is 100 psi, but an alternative pressure threshold may be used as needed. If pressure sensor 41 indicates a pressure greater than the fifth threshold pressure in block 414c, then in step 421c, controller 74 generates an "error" or "out-of-range" signal or report indicating a malfunction in solenoid valve 35. On the other hand, if pressure sensor 41 indicates a pressure less than or equal to the fifth threshold pressure in block 414c, then in step 415c, controller 74 commands both solenoid valves 34 and 35 to enter an "open" or energized state via solenoid actuator 72. In block 416c, controller 74 determines whether pressure sensor 41 indicates that the sixth threshold pressure has been exceeded. In this embodiment, such a sixth threshold pressure is 500 psi, but an alternative pressure threshold may be used as needed. If pressure sensor 41 indicates a pressure less than the sixth threshold pressure in block 416c, then in step 421c, controller 74 generates an "error" or "out-of-range" signal or report indicating a malfunction of solenoid valve 35. On the other hand, if pressure sensor 41 indicates a pressure greater than or equal to the sixth threshold pressure in block 416c, then in step 417c, controller 74 commands motor actuator 71 and solenoid actuator 72 to enter a "disabled" state. In step 418c, controller 74 generates an operation signal or report, and both solenoid valves 34 or 35 are diagnosed as fully operational. The controller 74 can also provide a valve closing command to place the safety valve 90 in the fail-safe closed position upon the occurrence of an error or out-of-range signal. The error or out-of-range signal can be sent to the surface controller 11 on the platform 100, and if no error is detected, the controller 74 can send an acknowledgment signal to the surface controller 11 on the platform 100. Although various pressure thresholds have been disclosed in this embodiment, other pressure thresholds may be used depending on the desired operating parameters of the system.

[0105] Therefore, a redundant fault-tolerant hydraulic system is provided for shutting off the safety valve assembly 91, and the critical components of the system can be periodically and automatically tested to diagnose or detect faults in these components.

[0106] Many changes and modifications are contemplated in relation to this invention. Therefore, although embodiments of the improved underground safety valve actuation system have been shown and described, and many alternatives have been discussed, those skilled in the art will readily understand that various additional changes and modifications can be made without departing from the spirit of the invention as defined and distinguished by the following claims.

Claims

1. An underground safety valve actuation system, comprising: Pipes, which are arranged in the well and form flow channels reaching the surface level for fluid originating from below the surface level; A safety valve located in the pipe below the surface level and operable between an open and closed position to control fluid flow in the flow passage; A hydraulic piston assembly, located in the conduit below the surface level, includes a first chamber and a piston situated between the first chamber and the safety valve; An electric motor, located in the conduit below the surface level, and configured to be supplied with current; A hydraulic pump, located in the conduit below the surface level, and configured to be driven by the motor and connected to the first chamber of the hydraulic piston assembly; A spring element located in the conduit below the surface level and configured to provide a spring force on the piston; A fluid reservoir connected to the pump and the first chamber; A first valve is connected to the first chamber and the fluid reservoir and has a first open position and a first closed position; A second valve is connected to the first chamber and the fluid reservoir and has a second open position and a second closed position; The pump, hydraulic piston assembly, first valve, second valve, and reservoir are connected in a substantially closed hydraulic system; The hydraulic system is configured in a first state to provide pressure in the first chamber, the pressure driving the safety valve from the closed position to the open position; The hydraulic system is configured in a second state to maintain a pressure level in the first chamber, which holds the safety valve in the open position. The hydraulic system is configured in a third state to release the pressure level in the first chamber via a first hydraulic release path extending through the first valve between the first chamber and the reservoir when the first valve is in the first open position. The hydraulic system is configured in a fourth state to release the pressure level within the first chamber via a second hydraulic release path extending through the second valve between the first chamber and the reservoir when the second valve is in the second open position; and The first hydraulic release path is independent of the second hydraulic release path, and the second hydraulic release path is independent of the first hydraulic release path; Thus, the pressure level in the first chamber holding the safety valve in the open position can be released via the first hydraulic release path when a fault exists in the second hydraulic release path, and can also be released via the second hydraulic release path when a fault exists in the first hydraulic release path.

2. The actuation system according to claim 1, wherein, The hydraulic system is configured to be in the second state to maintain the pressure level in the first chamber independently of the motor and the pump.

3. The actuation system according to claim 2, wherein, The second state includes the first valve in the first closed position and the second valve in the second closed position.

4. The actuation system according to claim 1, wherein, In the second state, the spring element is compressed between the piston and the pipe.

5. The actuation system according to claim 1, wherein, The hydraulic piston assembly consists of the first chamber connected to the closed hydraulic system.

6. The actuation system according to claim 1, wherein, The first hydraulic release path extends through the pump.

7. The actuation system according to claim 6, wherein, The first state includes providing a hydraulic pressure on the piston that is opposite to and exceeds the spring force, and the piston is translated in a first direction and actuates the safety valve to the open position.

8. The actuation system according to claim 7, wherein, The first state includes the first valve being in the first open position, and the motor being driven to control the flow of fluid through the pump to the first chamber.

9. The actuation system according to claim 8, wherein, The second hydraulic release path is independent of the pump.

10. The actuation system according to claim 9, wherein, The first state includes the first valve in the first open position and the second valve in the second closed position.

11. The actuation system according to claim 10, wherein: The hydraulic piston assembly includes a second chamber connected to the fluid reservoir; The piston separates the first chamber and the second chamber; and The positive pressure difference between the first chamber and the second chamber provides a hydraulic pressure on the piston that is opposite to and exceeds the spring force.

12. The actuation system according to claim 11, wherein, The negative pressure difference between the first chamber and the second chamber provides hydraulic pressure on the piston in a second direction opposite to the first direction.

13. The actuation system according to claim 12, wherein, The third state includes the negative pressure difference, the resulting hydraulic pressure, and the spring force, which causes the piston to translate in the second direction, thereby actuating the safety valve to the closed position.

14. The actuation system according to claim 6, wherein, The second state includes providing a hydraulic pressure on the piston that is opposite to and at least equal to the spring force.

15. The actuation system according to claim 14, wherein, The second state includes the first valve in the first closed position.

16. The actuation system of claim 15, wherein the second hydraulic release path is independent of the pump.

17. The actuation system according to claim 16, wherein, The second state includes the second valve being in the second closed position.

18. The actuation system according to claim 7, wherein, The third state includes providing a hydraulic pressure on the piston that is opposite to and less than the spring force, and the piston translating in a second direction opposite to the first direction, thereby actuating the safety valve to the closed position.

19. The actuation system according to claim 18, wherein, The second hydraulic release path is independent of the pump.

20. The actuation system according to claim 19, wherein, The third state includes the second valve being in the fault-closed position.

21. The actuation system according to claim 20, wherein, The third state includes driving the motor to control the fluid flow rate in the first hydraulic release path.

22. The actuation system according to claim 20, wherein, The third state includes releasing the motor and the pump to allow fluid to flow in the first hydraulic release path.

23. The actuation system according to claim 19, wherein, The third state includes the second valve in the second closed position, and the motor is driven to control the fluid flow rate in the first hydraulic release path.

24. The actuation system according to claim 19, wherein, The third state includes the second valve in the second closed position, and releases the motor and the pump to allow fluid to flow in the first hydraulic release path.

25. The actuation system according to claim 7, wherein, The fourth state includes providing a hydraulic pressure on the piston that is opposite to and less than the spring force, and the piston translating in a second direction opposite to the first direction, thereby actuating the safety valve to the closed position.

26. The actuation system according to claim 25, wherein, The fourth state includes the first valve in the fault-closed position and / or the pump in the fault-blocked flow position.

27. The actuation system according to claim 1, wherein, The first hydraulic release path is independent of the pump, and the second hydraulic release path is independent of the pump.

28. The actuation system according to claim 27, wherein, The first state includes providing a hydraulic pressure on the piston that is opposite to and exceeds the spring force, and the piston is translated in a first direction and actuates the safety valve to the open position.

29. The actuation system according to claim 28, wherein, The first state includes the first valve in the first closed position, the second valve in the second closed position, and the motor is driven to control the fluid flow through the pump to the first chamber.

30. The actuation system according to claim 29, wherein: The hydraulic piston assembly includes a second chamber connected to the fluid reservoir; The piston separates the first chamber and the second chamber; and The positive pressure difference between the first chamber and the second chamber provides the hydraulic pressure on the piston that is opposite to and exceeds the spring force.

31. The actuation system according to claim 30, wherein, The negative pressure difference between the first chamber and the second chamber provides hydraulic pressure on the piston in a second direction opposite to the first direction.

32. The actuation system according to claim 27, wherein, The second state includes providing a hydraulic pressure on the piston that is opposite to and at least equal to the spring force.

33. The actuation system according to claim 32, wherein, The second state includes the first valve in the first closed position and the second valve in the second closed position.

34. The actuation system of claim 33, comprising a check valve between the pump and the first chamber, the check valve being operatively arranged to allow fluid to flow from the pump to the first chamber and to prevent fluid from flowing from the first chamber to the pump, thereby maintaining the pressure level in the first chamber independently of the motor and the pump.

35. The actuation system according to claim 28, wherein, The third state includes providing a hydraulic pressure on the piston that is opposite to and less than the spring force, and the piston translating in a second direction opposite to the first direction, thereby actuating the safety valve to the closed position.

36. The actuation system according to claim 35, wherein, The third state includes the second valve being in the fault-closed position.

37. The actuation system of claim 35, wherein the third state includes the second valve in the second open position.

38. The actuation system according to claim 28, wherein, The fourth state includes providing a hydraulic pressure on the piston that is opposite to and less than the spring force, and the piston translating in a second direction opposite to the first direction, thereby actuating the safety valve to the closed position.

39. The actuation system according to claim 38, wherein, The fourth state includes the first valve being in the fault-closed position.

40. The actuation system of claim 38, wherein the fourth state includes the first valve in the first open position.

41. The actuation system according to claim 27, comprising: A third hydraulic release path, between the first chamber and the reservoir, extends through the pump when the motor and the pump are released to allow fluid to flow in the third hydraulic release path; and The third hydraulic release path is independent of the first hydraulic release path and the second hydraulic release path.

42. The actuation system according to claim 41, wherein, The system is configured in a fifth state to release the pressure level in the first chamber via the third hydraulic release path, which extends through the pump between the first chamber and the reservoir, when the motor and the pump are released to allow fluid to flow in the third hydraulic release path.

43. The actuation system according to claim 1, wherein, The fluid reservoir includes a pressure compensator configured to normalize the pressure difference between the outside and inside of the hydraulic system.

44. The actuation system according to claim 43, wherein, The pressure compensator includes a diaphragm or a piston.

45. The actuation system of claim 44, further comprising a position sensor configured to sense the position of the diaphragm or the piston.

46. ​​The actuation system according to claim 1, wherein, The first valve is an actively actuated valve arranged to open and allow equalization of fluid pressure on each side of the first valve, and the second valve is an actively actuated valve arranged to open and allow equalization of fluid pressure on each side of the second valve.

47. The actuation system according to claim 46, wherein, The first valve includes a solenoid valve arranged to open in the event of a power failure, thereby allowing equalization of fluid pressure on each side of the first valve, and the second valve includes a solenoid valve configured to open in the event of a power failure, thereby allowing equalization of fluid pressure on each side of the second valve.

48. The actuation system according to claim 1, wherein: The conduit includes an outer tubular surface oriented about a longitudinal axis and an inner tubular surface oriented about the longitudinal axis and defining the flow channel; The conduit includes a first modular cavity located between the inner tubular surface and the outer tubular surface; The conduit includes a second modular cavity located between the inner tubular surface and the outer tubular surface; The hydraulic piston assembly is disposed in the first module cavity; and The motor and the pump are disposed in the second module cavity.

49. The actuation system according to claim 48, wherein, The safety valve includes: A baffle element configured to rotate in the flow channel between the open position and the closed position about a hinge axis; The hinge axis is fixed relative to the pipe; A baffle actuating sleeve, oriented about the longitudinal axis and configured to move the baffle element from the closed position to the open position in the flow channel.

50. The actuation system according to claim 49, wherein, The hydraulic piston assembly includes a first actuator rod connected to the piston to move with the piston, a first actuator collar connected to the actuator rod to move with the actuator rod, and a baffle actuation sleeve connected to the actuator collar to move with the actuator collar.

51. The actuation system according to claim 50, wherein, The spring element is compressed between the piston and the pipe in the second state, and includes a helical spring oriented about the longitudinal axis and axially disposed between the hinge axis and the first actuator collar.

52. The actuation system according to claim 1, wherein, The hydraulic piston assembly includes a second chamber connected to the fluid reservoir, and the piston separates the first chamber and the second chamber.

53. The actuation system according to claim 52, wherein, The piston includes a first surface area exposed to the first chamber and a second surface area exposed to the second chamber.

54. The actuation system according to claim 53, wherein, The area of ​​the first surface is equal to or greater than the area of ​​the second surface.

55. The actuation system according to claim 54, wherein: The hydraulic piston assembly includes a hydraulic cylinder having a first end wall, and the piston is disposed within the hydraulic cylinder for sliding along a seal within the hydraulic cylinder; and The hydraulic piston assembly includes a first actuator rod connected to the piston to move with the piston and having a portion that sealably penetrates the first end wall.

56. The actuation system according to claim 55, wherein, The hydraulic cylinder has a second end wall, the hydraulic piston assembly includes a second actuator rod connected to the piston to move with the piston, and has a portion that seals through the second end wall, and the first surface area is equal to the second surface area.

57. The actuation system according to claim 1, comprising: An underground control electronics device is located below the surface level and is connected to the motor, the first valve, and the second valve; Surface controller above the surface level; A power cable that supplies power from the surface level to the underground control electronic equipment; and The communication cable between the underground control electronics and the surface controller.

58. The actuation system of claim 57, comprising a plurality of sensors configured to sense operating parameters of the system, and the underground control electronics comprising a signal processor communicating with the sensors and configured to receive sensor data from the sensors and output the data to the surface controller via the communication cable.

59. The actuation system of claim 1, further comprising a position sensor configured to sense the position of the piston.

60. The actuation system according to claim 59, wherein, The position sensor includes a first contact switch and a second contact switch.

61. The actuation system according to claim 1, wherein, The electric motor includes a variable speed electric motor, and the pump includes a reversible hydraulic pump.

62. The actuation system according to claim 1, wherein, The pump is selected from a group consisting of a fixed displacement pump, a variable displacement pump, a two-port pump, and a three-port pump.

63. The actuation system according to claim 1, comprising: An underground controller, which is below the surface level and connected to the motor, the first valve, and the second valve; A subsurface sensor located below the surface level, configured to sense operating parameters of components of the actuation system and connected to the controller; and The underground controller includes a non-transitory computer-readable medium storing one or more instructions that can be executed by the underground controller to perform diagnostic tests on the components of the actuation system based on the operating parameters of the components of the actuation system sensed by the underground sensors.

64. The actuation system according to claim 63, wherein: The fluid reservoir includes a pressure compensator; The components of the actuation system are selected from the pressure compensator, the hydraulic piston assembly, the first valve, and the second valve; and The underground sensors are selected from position sensors, current sensors, and pressure sensors.

65. The actuation system according to claim 64, wherein, The underground sensor includes a position sensor configured to sense the position of the piston in the hydraulic piston assembly, and the diagnostic test includes: The command instructs the piston to move to a preset position; Monitor the position sensor after the commanded movement; and The operating state of the hydraulic piston assembly is determined based on the output from the monitored position sensor or the absence of an output.

66. The actuation system according to claim 65, wherein, The step of determining the operating state of the hydraulic piston assembly is a function of a threshold time elapsed since the commanded movement.

67. The actuation system according to claim 64, wherein, The pressure compensator includes a compensator diaphragm or a compensator piston, the underground sensor includes a compensator position sensor configured to sense the position of the compensator diaphragm or the compensator piston, and the diagnostic test includes: Command the piston of the hydraulic piston assembly to move to a preset position; Monitor the compensator position sensor after the commanded movement; and The operating state of the pressure compensator is determined based on the output of the monitored compensator position sensor or the absence of an output.

68. The actuation system according to claim 67, wherein, The step of determining the operating state of the pressure compensator is a function of the threshold time elapsed since the commanded movement.

69. The actuation system according to claim 64, wherein, The first valve includes a solenoid valve arranged to open in the event of a power failure, thereby allowing fluid pressure equalization on each side of the first valve. The underground sensor includes a current sensor configured to sense the current to the solenoid valve, and the diagnostic test includes: The command energizes the solenoid valve; Monitor the current sensor after the commanded power-on; and The operating state of the solenoid valve is determined based on the output of the monitored current sensor.

70. The actuation system according to claim 69, wherein, The step of determining the operating state of the solenoid valve is a function of current reference data stored in the underground controller.

71. The actuation system according to claim 64, wherein, The first valve includes a solenoid valve arranged to open in the event of a power failure, thereby allowing fluid pressure equalization on each side of the first valve. The underground sensor includes a valve position sensor configured to sense the position of the solenoid valve. The diagnostic test includes: The command energizes the solenoid valve; Monitor the valve position sensor after the commanded power-on; and The operating state of the solenoid valve is determined based on the output from the monitored valve position sensor or the absence of an output.

72. The actuation system according to claim 64, wherein, The first valve includes a solenoid valve arranged to open in the event of a power failure, thereby allowing equalization of fluid pressure on each side of the first valve; the pump includes a rotary pump; the underground sensor includes a pressure sensor configured to sense pressure in the closed hydraulic system; and the diagnostic test includes: The command was given to de-energize the solenoid valve; The command specifies that the rotary pump should rotate at a reference rotational speed; The pressure sensor is monitored after the solenoid valve is commanded to be de-energized; and The operating status of the solenoid valve is determined based on the output of the monitored pressure sensor.

73. The actuation system according to claim 69, wherein, The step of determining the operating state of the solenoid valve is a function of the stored pressure reference data.

74. The actuation system according to claim 72, wherein, The diagnostic tests include: The command energizes the solenoid valve; and The pressure sensor is monitored after the solenoid valve is commanded to be energized.

Images