Single-acting pneumatic actuator control system

Abstract

This invention belongs to the field of valve technology and discloses a single-acting pneumatic actuator control system, including an air supply line, a pneumatic pilot valve, a first solenoid valve, a pilot circuit, and a delayed discharge circuit. When the first solenoid valve is in its first home position, the second inlet is connected to the first outlet. The delayed discharge circuit is configured to release the air pressure in the control air chamber and, after a preset time, gradually reduce it to below a set value to cut off the pneumatic pilot valve. In the event of a power outage across the entire platform, the delayed discharge circuit enables the entire control system to automatically switch to a pure pneumatic delayed mode, preventing the BDV from immediately opening due to power failure of the first solenoid valve. This significantly improves the environmental adaptability and long-term operational reliability of the control system in extreme and harsh environments such as offshore platforms and flammable and explosive environments, thereby enhancing safety performance.

Description

Technical Field

[0001] This invention relates to the field of valve technology, and in particular to a control system for a single-acting pneumatic actuator. Background Technology

[0002] Traditional BDV (Breakdown Valve) control systems primarily rely on electrical / electronic logic control (such as PLCs and SIS systems). Specifically, the central control system sends electrical signals to the solenoid valve on the valve based on sensor signals, driving the single-acting pneumatic actuator to open or close the valve.

[0003] However, in the extremely harsh environment of marine platforms, when a platform-wide power outage, network failure, or common logical error in the control system occurs, all BDVs that rely on the same electronic control system may be erroneously triggered and turned on at the same time. This could cause the flare system to be flooded with exhaust gases far exceeding the design load, potentially leading to catastrophic consequences such as flare extinguishing, backfire, or even explosion.

[0004] Therefore, the above problems urgently need to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide a single-acting pneumatic actuator control system to prevent all BDVs from being activated simultaneously in the event of a platform-wide power outage, network failure, or common logic error in the control system, thereby improving safety performance.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A single-acting pneumatic actuator control system includes:

[0008] An air supply path is provided between an air source and a single-acting pneumatic actuator, and is configured to supply air to the single-acting pneumatic actuator;

[0009] A pneumatic pilot valve is connected in series in the air supply circuit and has a control chamber for controlling its on / off state.

[0010] The first solenoid valve has a first inlet connected to a pilot circuit, a second inlet connected to a delayed discharge circuit, and a first outlet connected to the control air chamber, and the first solenoid valve is capable of switching between a first operating position and a first home position.

[0011] When the first solenoid valve is in the first operating position, the first inlet is connected to the first outlet, and the pilot circuit is configured to supply air to the control air chamber, so that the internal air pressure is higher than the set value, so as to activate the pneumatic pilot valve.

[0012] When the first solenoid valve is in the first home position, the second inlet is connected to the first outlet. The delayed discharge circuit is configured to release the air pressure in the control air chamber and, after a preset time, gradually reduce it to below the set value to cut off the pneumatic pilot valve.

[0013] Preferably, the delayed emission circuit includes:

[0014] The exhaust pipe has one end connected to the second inlet and the other end connected to the atmosphere;

[0015] A pressure tank is connected to the exhaust pipe;

[0016] The first ball valve is disposed between the pressure tank and the exhaust pipe and is communicatively connected to the first solenoid valve. When the first solenoid valve is in the first working position, the first ball valve is in the open state, and when the first solenoid valve is in the first home position, the first ball valve is in the open state.

[0017] A throttle valve is located downstream of the pressure tank along the exhaust direction.

[0018] Preferably, the single-acting pneumatic actuator control system further includes a second solenoid valve that is communicatively connected to the first solenoid valve. The second solenoid valve has a third inlet and a second outlet for being connected in series to the pilot circuit, and the second solenoid valve is located upstream of the first solenoid valve.

[0019] The second solenoid valve also has a third outlet that is connected to the atmosphere, and the second solenoid valve can switch between a second operating position and a second home position. The exhaust pipe is connected to the pilot circuit and is located between the second outlet and the first inlet.

[0020] When the second solenoid valve is in the second operating position and the first solenoid valve is in the first operating position, the third inlet is connected to the first inlet and the pressure tank.

[0021] When the second solenoid valve is in the second home position and the first solenoid valve is in the first home position, the exhaust pipe is connected to the atmosphere.

[0022] Preferably, the delayed emission circuit further includes:

[0023] An exhaust branch pipe is connected to the exhaust pipe and is located upstream of the pressure tank;

[0024] The second ball valve is located in the exhaust branch pipe and is communicatively connected to the pneumatic pilot valve. When the pneumatic pilot valve is in the cut-off state, the second ball valve is turned on.

[0025] The first muffler is located at the end of the exhaust branch pipe.

[0026] Preferably, the pneumatic pilot valve has a fourth inlet and a fourth outlet connected to the air supply circuit, and also has a fifth outlet connected to the atmosphere.

[0027] When the pneumatic pilot valve is in the open state, the fourth inlet is connected to the fourth outlet; when the pneumatic pilot valve is in the closed state, the fourth outlet is connected to the fifth outlet.

[0028] Preferably, a second silencer is provided at the fifth outlet.

[0029] Preferably, multiple quick-exhaust valves are connected in parallel on the air supply line, and each of the multiple quick-exhaust valves is configured to correspond one-to-one with the drive air line of the single-acting pneumatic actuator.

[0030] Multiple of the aforementioned quick-exhaust valves are communicatively connected to the pneumatic pilot valve to switch between exhaust and venting states.

[0031] Preferably, the pilot circuit includes:

[0032] The pilot air tube is connected at one end to the control air chamber and at the other end to the air supply circuit;

[0033] A pressure stabilizing component, connected to the pilot air tube and located downstream of the first solenoid valve, is configured to stabilize the air pressure inside the pilot air tube when air pressure fluctuations occur.

[0034] Preferably, the voltage regulator component includes:

[0035] A pressure-stabilizing gas tank is connected to the pilot gas pipe;

[0036] The third ball valve is located between the pressure-stabilizing gas tank and the pilot gas pipe, and is communicatively connected to the first solenoid valve to change its on / off state.

[0037] A vent valve is installed in the pressure-stabilizing gas tank and is set with a venting threshold.

[0038] Preferably, the single-acting pneumatic actuator control system further includes:

[0039] A spare gas cylinder is connected to the gas supply line;

[0040] The fourth ball valve is located between the backup gas tank and the gas supply line and is configured to connect the backup gas tank and the gas supply line when the gas source fails.

[0041] The beneficial effects of this invention are:

[0042] The single-acting pneumatic actuator control system proposed in this invention, when the BDV needs to be closed, switches the first solenoid valve from the first home position to the first working position, thereby enabling the pilot circuit to be open. The pilot circuit can supply gas to the control air chamber. After the air pressure reaches the set value, the pneumatic pilot valve can switch from the third home position to the third working position, thereby enabling the air supply path to be open. Under the action of the air supply path, air can be supplied to the single-acting pneumatic actuator to drive the piston rod of the single-acting pneumatic actuator to extend, thus closing the BDV. The actual air pressure in the control air chamber must be greater than the set value. When the BDV needs to be opened, the first solenoid valve resets from the first working position to the first home position, the pilot circuit is disconnected, and the air pressure in the control air chamber will gradually decrease below the set value under the action of the delayed discharge circuit, thus disconnecting the air supply path. Under the action of its own return spring, the single-acting pneumatic actuator can reset the piston rod, thus opening the BDV. Furthermore, under the action of the delayed discharge circuit, when the first solenoid valve is in its first home position, the pressure value in the control air chamber can be maintained above the set value for a preset time, thus keeping the BDV in the closed state. The set value is the minimum air pressure required by the single-acting pneumatic actuator; that is, when the set value in the control air chamber is lower than the set value, the gas pressure in the single-acting pneumatic actuator's chamber is less than the reset force of the return spring. Different preset times can be set for different BDVs to prevent all BDVs from opening simultaneously, which could lead to catastrophic consequences such as torch extinguishing, backfire, or even explosion. In addition, during a platform-wide power outage, network failure, or a common logical error in the control system, the delayed discharge circuit can automatically switch the entire control system to a pure pneumatic delayed mode, preventing the first solenoid valve from immediately opening the BDVs due to power failure. Setting different preset times ensures that the closing actions of each BDV are performed in an orderly manner, significantly improving the environmental adaptability and long-term operational reliability of the control system in extreme and harsh environments such as offshore platforms and flammable and explosive environments, thereby enhancing safety performance. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the single-acting pneumatic actuator control system in this invention.

[0044] In the picture:

[0045] 100. Single-acting pneumatic actuator; 200. BDV;

[0046] 1. Air supply line; 2. Pneumatic pilot valve; 3. First solenoid valve;

[0047] 4. Pilot circuit; 41. Pilot gas pipe; 42. Pressure stabilizing assembly; 421. Pressure stabilizing gas tank; 422. Third ball valve; 423. Relief valve;

[0048] 5. Delayed emission circuit; 51. Exhaust pipe; 52. Pressure tank; 53. First ball valve; 54. Throttle valve; 55. Exhaust branch pipe; 56. Second ball valve; 57. First silencer;

[0049] 6. Second solenoid valve; 7. Second silencer; 8. Quick exhaust valve; 9. Spare gas tank; 10. Fourth ball valve; 11. Third silencer. Detailed Implementation

[0050] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0051] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0052] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0053] In this application, those skilled in the art will understand that relative terms (e.g., “about,” “approximately,” “basically,” etc.) used in conjunction with quantities or conditions are to include the values ​​and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances associated with the particular value due to manufacturing, assembly, use, etc. Such terms should also be considered as disclosing a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​that do not use relative terms should also be disclosed as specific values ​​with tolerances. Furthermore, “basically” when expressing relative angular relationships (e.g., substantially parallel, substantially perpendicular) may refer to a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) added to or subtracted from the indicated angle.

[0054] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0055] Please see Figure 1 This embodiment proposes a single-acting pneumatic actuator control system for supplying air to the single-acting pneumatic actuator 100, thereby enabling the corresponding BDV200 to be in a closed state. When the power is off, the opening time of the single-acting pneumatic actuator 100 can be delayed. For different BDV200s, controlling different opening times can avoid safety accidents caused by the simultaneous opening of each BDV200.

[0056] The control system includes an air supply path 1, a pneumatic pilot valve 2, a first solenoid valve 3, a pilot circuit 4, and a delayed discharge circuit 5. The air supply path 1 is located between an air source and a single-acting pneumatic actuator 100 and is configured to supply air to the single-acting pneumatic actuator 100. The pneumatic pilot valve 2 is connected in series with the air supply path 1 and has a control air chamber for controlling its on / off state. The first solenoid valve 3 has a first inlet connected to the pilot circuit 4, a second inlet connected to the delayed discharge circuit 5, and a first outlet connected to the control air chamber. Valve 3 can switch between a first operating position and a first home position. When the first solenoid valve 3 is in the first operating position, the first inlet and the first outlet are connected, and the pilot circuit 4 is configured to supply air to the control air chamber, making its internal air pressure higher than the set value, so as to conduct the pneumatic pilot valve 2. When the first solenoid valve 3 is in the first home position, the second inlet and the first outlet are connected, and the delayed discharge circuit 5 is configured to release the air pressure in the control air chamber, and after a preset time, gradually reduce it to below the set value, so as to cut off the pneumatic pilot valve 2.

[0057] Understandably, when BDV200 needs to be shut down, the first solenoid valve 3 (preferably the KSY-solenoid valve in the prior art) switches from the first home position to the first working position, thereby enabling the pilot circuit 4 to be turned on. The pilot circuit 4 can supply gas to the control air chamber. After the air pressure reaches the set value, it can enable the pneumatic pilot valve 2 to switch from the third home position to the third working position, thereby enabling the air supply line 1 to be turned on. Under the action of the air supply line 1, air can be supplied to the single-acting pneumatic actuator 100 to drive the piston of the single-acting pneumatic actuator 100. When the rod extends, BDV200 closes. The actual air pressure in the control chamber (e.g., 700 kPag) must be greater than the set value (e.g., 550 kPag). When BDV200 needs to be opened, the first solenoid valve 3 returns from the first working position to the first home position, the pilot circuit 4 is disconnected, and the air pressure in the control chamber gradually decreases below the set value under the action of the delayed discharge circuit 5, which can disconnect the air supply circuit 1. Under the action of its own return spring, the single-acting pneumatic actuator 100 can reset the piston rod, and BDV200 opens.

[0058] Similarly, it is understandable that, under the action of the delayed discharge circuit 5, when the first solenoid valve is in its first home position, the pressure value in the control air chamber can be maintained above the set value for a preset time, so that the BDV200 remains in the closed state. The set value is the minimum air pressure value required by the single-acting pneumatic actuator 100; that is, when the set value in the control air chamber is lower than the set value, the gas pressure in the chamber of the single-acting pneumatic actuator 100 is less than the reset force of the return spring. Furthermore, different preset times can be set for different BDV200s to avoid the simultaneous opening of all BDV200s, which could lead to catastrophic consequences such as torch extinguishing, backfire, or even explosion.

[0059] In addition, in the event of a power outage, network failure, or common logical error in the control system across the entire platform, the delayed emission circuit 5 can automatically switch the entire control system to a pure pneumatic delay mode, preventing the first solenoid valve 3 from immediately opening due to power failure. This significantly improves the environmental adaptability and long-term operational reliability of the control system in extreme and harsh environments such as offshore platforms and flammable and explosive environments, thereby enhancing safety performance.

[0060] In this embodiment, the delayed discharge circuit 5 includes an exhaust pipe 51, a pressure tank 52, a first ball valve 53, and a throttle valve 54. One end of the exhaust pipe 51 is connected to the second inlet, and the other end is connected to the atmosphere. The pressure tank 52 is connected to the exhaust pipe 51. The first ball valve 53 is located between the pressure tank 52 and the exhaust pipe 51 and is communicatively connected to the first solenoid valve 3. When the first solenoid valve 3 is in the first operating position, the first ball valve 53 is in the open state; when the first solenoid valve 3 is in the first home position, the first ball valve 53 is in the open state. Along the exhaust direction, the throttle valve 54 is located downstream of the pressure tank 52. It can be understood that when the first solenoid valve 3 is in the first operating position, the first ball valve 53 is in the open state, isolating the pressure tank 52 from the pilot circuit 4 to prevent it from interfering with the normal control of the pneumatic pilot valve 2. When the first solenoid valve 3 switches to the first home position, the first ball valve 53 is instantly open, immediately connecting the pressure tank 52 to the discharge circuit to start working. This configuration eliminates the risks that may arise from electrical signal delays or asynchrony, ensuring the immediacy and determinism of safety trigger actions. Under the action of the pressure tank 52, the rate of pressure drop in the control chamber can be effectively buffered during the release process, avoiding the uncontrollable time problem caused by direct rapid discharge. The throttle valve 54 allows for precise and continuous adjustment of the discharge airflow rate, so that different delay times can be set according to different BDV200s, enabling the shutdown actions of each BDV to be carried out in an orderly manner. This significantly improves the environmental adaptability and long-term operational reliability of the control system in extreme and harsh environments such as offshore platforms and flammable and explosive environments, thereby enhancing safety performance.

[0061] Furthermore, the single-acting pneumatic actuator control system also includes a second solenoid valve 6 communicatively connected to the first solenoid valve 3. The second solenoid valve 6 has a third inlet and a second outlet for series connection to the pilot circuit 4, and is located upstream of the first solenoid valve 3. The second solenoid valve 6 also has a third outlet communicating with the atmosphere, and can switch between a second operating position and a second home position. The exhaust pipe 51 is connected to the pilot circuit 4 and is located between the second outlet and the first inlet. When the second solenoid valve 6 is in the second operating position and the first solenoid valve 3 is in the first operating position, the third inlet is connected to the first inlet and the pressurized air tank 52. When the second solenoid valve 6 is in the second home position and the first solenoid valve 3 is in the first home position, the exhaust pipe 51 is connected to the atmosphere.

[0062] Understandably, the synergistic action of the first solenoid valve 3 and the second solenoid valve 6 (preferably the BDY-solenoid valve in the prior art) enables the construction of a dual-solenoid valve redundancy architecture, improving trigger reliability and preventing single-point accidental activation, thereby further enhancing safety performance. Furthermore, when the second solenoid valve 6 is in the second operating position, it can supply gas to the pressure tank 52, facilitating the subsequent delayed opening of the BDV200. When the second solenoid valve 6 is in the first home position, it can connect the delayed discharge circuit 5 to the atmospheric environment, facilitating exhaust, and a third silencer 11 is provided at the third outlet to reduce noise generated during gas discharge.

[0063] Specifically, if the first solenoid valve 3 is in the first operating position and the second solenoid valve 6 is in the second home position, the control system can report an error. If the first solenoid valve 3 is in the first home position and the second solenoid valve 6 is in the second operating position, the pilot circuit 4 is disconnected and the delayed discharge circuit 5 is connected. However, since the pilot gas source connected to the pilot circuit 4 has not stopped supplying gas, the pressure value in the delayed discharge circuit 5 and the control gas chamber remains unchanged, thus keeping the BDV200 in the closed state. It should be noted that the throttle valve 54 integrates a check valve and forms two circuits. When supplying gas to the pressure tank 52, the throttle orifice in the throttle valve 54 is closed, and the gas enters the pressure tank 52 through the check valve. During depressurization, the opening and closing degree of the throttle orifice is controlled according to the required delay time.

[0064] In addition, the delayed emission circuit 5 also includes an exhaust branch pipe 55, a second ball valve 56, and a first muffler 57. The exhaust branch pipe 55 is connected to the exhaust pipe 51 and is located upstream of the pressurized gas tank 52. The second ball valve 56 is located on the exhaust branch pipe 55 and is communicatively connected to the pneumatic pilot valve 2. When the pneumatic pilot valve 2 is in the cut-off state, the second ball valve 56 is open. The first muffler 57 is located at the end of the exhaust branch pipe 55. Understandably, when the gas in the control chamber is released through the delay circuit, once the internal air pressure drops below the set value, the valve core of the pneumatic pilot valve 2 will be about to or begin to mechanically move to the cut-off position under the action of the air pressure difference. This will directly trigger the second ball valve 56, which is in communication with it, to immediately switch from the disconnected state to the open state. This will allow the gas in the delay discharge circuit 5 to be released quickly, enabling the pneumatic pilot valve 2 to quickly switch from the third working position to the third home position. This will allow the instantaneous triggering of the opening action of the BDV200 to be activated, shortening the lag time from triggering to the valve starting to operate. The setting of the first silencer 57 can reduce the noise generated during gas discharge.

[0065] In this embodiment, the pneumatic pilot valve 2 has a fourth inlet and a fourth outlet connected to the air supply circuit 1, and a fifth outlet connected to the atmosphere. When the pneumatic pilot valve 2 is in the open state, the fourth inlet and the fourth outlet are connected; when the pneumatic pilot valve 2 is in the closed state, the fourth outlet and the fifth outlet are connected. It can be understood that when the pneumatic pilot valve 2 is in the third operating position, the fourth inlet and the fifth outlet are connected, and the air supply circuit 1 is open, supplying air to the single-acting pneumatic actuator 100. When in the third home position, the fourth outlet and the fifth outlet are connected, the air supply circuit 1 is closed, stopping the supply of air to the pneumatic actuator, and the gas in the air chamber of the pneumatic actuator 100 can be discharged through the fifth outlet, causing its internal air pressure to gradually decrease to zero. Under the action of the return spring, the BDV200 can be opened.

[0066] The fifth outlet is equipped with a second silencer 7, which can reduce the noise generated during gas emission.

[0067] To ensure the actuation force of the single-acting pneumatic actuator 100, at least two pistons are typically installed, with each piston corresponding to an air chamber and a drive air path. Therefore, multiple quick-exhaust valves 8 are connected in parallel on the air supply line 1. Each quick-exhaust valve 8 corresponds one-to-one with a drive air path of the single-acting pneumatic actuator 100. That is, after passing through the pneumatic pilot valve 2, the air supply line 1 can be divided into multiple drive air paths communicating with different air chambers. All quick-exhaust valves 8 are communicatively connected to the pneumatic pilot valve 2 to switch between exhaust and guide air states. It is understandable that when the pneumatic pilot valve 2 is in the third operating position, the quick-release valve 8 is in the conducting state, its air inlet is connected to the corresponding air chamber, and its exhaust port is tightly closed by the valve core of the quick-release valve 8 to prevent gas leakage. When the pneumatic pilot valve 2 is in the third home position, it can trigger the quick-release valve 8, and the valve core of the quick-release valve 8 moves to connect the exhaust port with the air chamber, so that the quick-release valve 8 switches from the air guiding state to the exhaust state, thereby enabling the gas in each drive air circuit to be discharged quickly. Under the action of multiple quick-release valves 8, all air chambers of the single-acting pneumatic actuator 100 can be depressurized at nearly the same rate at the same time, so that the piston rod is subjected to balanced force, thereby greatly reducing mechanical stress when the BDV200 is opened, and improving the life and operational reliability of the single-acting pneumatic actuator 100.

[0068] In this embodiment, the pilot circuit 4 includes a pilot air pipe 41 and a pressure stabilizing component 42. One end of the pilot air pipe 41 is connected to the control air chamber, and the other end is connected to the air supply circuit 1. The pressure stabilizing component 42 is connected to the pilot air pipe 41 and is located downstream of the first solenoid valve 3. It is configured to stabilize the air pressure inside the pilot air pipe 41 when the air pressure inside the pilot air pipe 41 fluctuates. It can be understood that connecting the pilot air pipe 41 to the air supply circuit 1 allows the air supply circuit 1, the pilot circuit 4, and the delayed emission circuit 5 to share the same air source, eliminating the need for an additional air source.

[0069] Furthermore, when the BDV200 needs to remain closed for an extended period, the control chamber of the pneumatic pilot valve 2 must maintain a stable pressure higher than the set value. The pressure stabilizing component 42 can absorb and dampen instantaneous pressure fluctuations from the upstream air source, thereby providing a smooth and stable pilot pressure for the control chamber. This ensures that the pneumatic pilot valve 2 only operates when the first solenoid valve 3 issues a clear on (when the first solenoid valve 3 is in the first operating position) or release (when the first solenoid valve 3 is in the first home position) command. This prevents the pneumatic pilot valve 2 from being in an unstable "micro-motion" state near the critical point due to fluctuations in pilot pressure with the air source, which would accelerate wear or even cause unexpected safety shutdowns due to instantaneous pressure drops.

[0070] The pressure stabilizing component 42 includes a pressure stabilizing gas tank 421 and a third ball valve 422. The pressure stabilizing gas tank 421 is connected to the pilot gas pipe 41. The third ball valve 422 is located between the pressure stabilizing gas tank 421 and the pilot gas pipe 41 and is communicatively connected to the first solenoid valve 3 to change its on / off state. The venting valve 423 is located in the pressure stabilizing gas tank 421 and is set with a venting threshold. The venting threshold can be determined according to a set value (such as 700 kPag), and no specific limitation is made here.

[0071] Understandably, when the first solenoid valve 3 is in the first operating position, the third ball valve 422 is open, enabling the pilot air pipe 41 to supply air to the control air chamber while simultaneously supplying air to the pressure stabilizing gas tank 421. This allows the pressure stabilizing gas tank 421 to supply air to the control air chamber when the gas source pressure decreases, thus stabilizing the air pressure within the control air chamber. When the gas source pressure increases, the pressure is released using the relief valve 423 on the pressure stabilizing gas tank 421 to achieve pressure stabilization. When the first solenoid valve 3 is in the first home position, the third ball valve 422 is closed, cutting off the connection between the pressure stabilizing gas tank 421 and the control air chamber. This prevents the gas stored inside the pressure stabilizing gas tank 421 from flowing back into the releasing control air chamber, ensuring that the release speed is not affected and that the shut-off action is swift and accurate.

[0072] In this embodiment, the single-acting pneumatic actuator control system further includes a backup air tank 9 and a fourth ball valve 10. The backup air tank 9 is connected to the air supply line 1. The fourth ball valve 10 is located between the backup air tank 9 and the air supply line 1 and is configured to connect the backup air tank 9 and the air supply line 1 when the air source fails. It is understood that when the air source fails, the air pressure in the air supply line 1 decreases, and the pressure on the valve core of the fourth ball valve 10 decreases. When the pressure drops to a critical point where it can no longer overcome the preload force of the spring in the fourth ball valve 10, the spring force begins to push the valve core to move, thereby opening the fourth ball valve 10 and enabling the backup air tank 9 to supply air to the air supply line 1 to maintain the BDV200 in a closed state.

[0073] The gas storage capacity in the spare gas tank 9 must be sufficient to enable at least two BDV200 switches.

[0074] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A single-acting pneumatic actuator control system, characterized in that, include: An air supply passage (1) is provided between an air source and a single-acting pneumatic actuator (100) and is configured to supply air to the single-acting pneumatic actuator (100); A pneumatic pilot valve (2) is connected in series in the air supply circuit (1) and has a control air chamber for controlling its on / off state; The first solenoid valve (3) has a first inlet connected to the pilot circuit (4), a second inlet connected to the delayed discharge circuit (5), and a first outlet connected to the control air chamber, and the first solenoid valve (3) can switch between a first working position and a first home position. When the first solenoid valve (3) is in the first working position, the first inlet is connected to the first outlet, and the pilot circuit (4) is configured to supply air to the control air chamber so that the internal air pressure is higher than the set value, so as to open the pneumatic pilot valve (2). When the first solenoid valve (3) is in the first original position, the second inlet is connected to the first outlet, and the delayed discharge circuit (5) is configured to release the air pressure in the control air chamber and gradually reduce it to below the set value after a preset time, so as to cut off the pneumatic pilot valve (2). The delayed emission circuit (5) includes: The exhaust pipe (51) is connected at one end to the second inlet and at the other end to the atmosphere; A pressure tank (52) is connected to the exhaust pipe (51); The first ball valve (53) is located between the pressure tank (52) and the exhaust pipe (51) and is communicatively connected to the first solenoid valve (3). When the first solenoid valve (3) is in the first working position, the first ball valve (53) is in the open state. When the first solenoid valve (3) is in the first original position, the first ball valve (53) is in the open state. A throttle valve (54) is located downstream of the pressure tank (52) along the exhaust direction.

2. The single-acting pneumatic actuator control system according to claim 1, characterized in that, The single-acting pneumatic actuator control system further includes a second solenoid valve (6) that is communicatively connected to the first solenoid valve (3). The second solenoid valve (6) has a third inlet and a second outlet for being connected in series to the pilot circuit (4), and the second solenoid valve (6) is located upstream of the first solenoid valve (3). The second solenoid valve (6) also has a third outlet connected to the atmosphere, and the second solenoid valve (6) can switch between a second operating position and a second home position. The exhaust pipe (51) is connected to the pilot circuit (4) and is located between the second outlet and the first inlet. When the second solenoid valve (6) is in the second operating position and the first solenoid valve (3) is in the first operating position, the third inlet is connected to the first inlet and the pressure tank (52). When the second solenoid valve (6) is in the second home position and the first solenoid valve (3) is in the first home position, the exhaust pipe (51) is connected to the atmosphere.

3. The single-acting pneumatic actuator control system according to claim 1, characterized in that, The delayed emission circuit (5) also includes: An exhaust branch pipe (55) is connected to the exhaust pipe (51) and is located upstream of the pressure tank (52); The second ball valve (56) is located in the exhaust branch pipe (55) and is communicatively connected to the pneumatic pilot valve (2). When the pneumatic pilot valve (2) is in the cut-off state, the second ball valve (56) is open. The first muffler (57) is located at the end of the exhaust branch pipe (55).

4. The single-acting pneumatic actuator control system according to claim 1, characterized in that, The pneumatic pilot valve (2) has a fourth inlet and a fourth outlet connected to the air supply circuit (1), and also has a fifth outlet connected to the atmosphere; When the pneumatic pilot valve (2) is in the open state, the fourth inlet is connected to the fourth outlet; when the pneumatic pilot valve (2) is in the closed state, the fourth outlet is connected to the fifth outlet.

5. The single-acting pneumatic actuator control system according to claim 4, characterized in that, A second silencer (7) is installed at the fifth exit.

6. The single-acting pneumatic actuator control system according to claim 1, characterized in that, Multiple quick-release valves (8) are connected in parallel on the air supply circuit (1), and the multiple quick-release valves (8) are configured one-to-one with the drive air circuit of the single-acting pneumatic actuator (100). Multiple quick exhaust valves (8) are communicatively connected to the pneumatic pilot valve (2) to switch between exhaust and venting states.

7. The single-acting pneumatic actuator control system according to claim 1, characterized in that, The pilot circuit (4) includes: The pilot air tube (41) is connected at one end to the control air chamber and at the other end to the air supply circuit (1); The pressure stabilizing component (42), which is connected to the pilot air pipe (41) and located downstream of the first solenoid valve (3), is configured to stabilize the air pressure inside the pilot air pipe (41) when the air pressure inside the pilot air pipe (41) fluctuates.

8. The single-acting pneumatic actuator control system according to claim 7, characterized in that, The voltage regulator component (42) includes: A pressure-stabilizing gas tank (421) is connected to the pilot gas pipe (41); The third ball valve (422) is located between the pressure stabilizing gas tank (421) and the pilot gas pipe (41), and is communicatively connected to the first solenoid valve (3) to change its on / off state; A vent valve (423) is provided in the pressure-stabilizing gas tank (421) and is set with a venting threshold.

9. The single-acting pneumatic actuator control system according to claim 1, characterized in that, The single-acting pneumatic actuator control system also includes: A spare gas cylinder (9) is connected to the gas supply line (1); The fourth ball valve (10) is located between the backup gas tank (9) and the gas supply line (1) and is configured to connect the backup gas tank (9) and the gas supply line (1) when the gas source fails.

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