Nuclear power plant steam energy supply rapid isolation valve, isolation system and isolation method

Abstract

The invention belongs to the technical field of rapid isolating valves, aims to solve the problems that in the prior art, an isolating valve is low in response speed and poor in operation stability, and rapid and reliable isolation cannot be achieved under the emergency situation, and discloses a nuclear power plant steam energy supply rapid isolating valve, an isolating system and an isolating method.The isolating valve comprises a valve body, a support and a flashboard assembly; a circular middle cavity is formed in the valve body and is provided with a guide rib, and a boss is arranged at the bottom in the valve body; the bracket is detachably connected with the valve body; the gate plate assembly is installed at the tail end of the valve rod and comprises two gate plates, a gate plate frame and a lower wedge block, the gate plate frame and the lower wedge block are vertically arranged between the two gate plates, the gate plate frame moves along the wedge face, and the lower wedge block moves in the flow channel direction. According to the invention, a rapid and reliable isolation function can be realized in key applications such as nuclear power station steam energy supply, and the safety and response efficiency of the system are improved.

Description

Technical Field

[0001] The present application belongs to the technical field of rapid isolation valves, and in particular, relates to a nuclear power plant steam power supply rapid isolation valve, an isolation system, and an isolation method. Background Art

[0002] The nuclear power plant steam supply rapid isolation valve is a key safety device designed to quickly cut off the flow of steam or other media in nuclear power plants and other high-risk industrial environments, thereby protecting the safety of the unit and personnel in an emergency. The rapid isolation valve not only improves the operational safety of nuclear power plants, but also ensures a rapid response in the event of a system failure to prevent the spread of potential accidents.

[0003] At the same time, fast isolation valves are particularly important in applications where nuclear energy is coupled with other forms of energy. In these systems, nuclear energy, as the main or auxiliary energy supply, may need to share key steam and heat transmission networks with other energy systems. In this case, fast isolation valves can serve as an important safety boundary to ensure that when any system component fails, the flow of media between different energy systems can be quickly cut off to avoid possible cross-contamination or wider system impact.

[0004] The existing nuclear power plant steam-powered rapid isolation valve, isolation system and its operation method have many deficiencies in terms of safety, response speed and reliability. First, the isolation valve has insufficient response speed in emergency situations, which makes it difficult to meet the demand for immediate isolation in the high-risk environment of nuclear power plants. At the same time, due to component wear and harsh working conditions, the reliability of the isolation valve will gradually decrease, affecting the isolation effect in emergencies. In addition, the sealing effect of the existing isolation valve is unstable under different pressure conditions, especially under high-pressure shock, the sealing structure is easily damaged, increasing the risk of medium leakage. The system generally lacks self-detection and status feedback functions, and cannot monitor the valve status or feedback abnormal information in real time, making it difficult for the system to identify and respond in time under abnormal conditions, thereby reducing the safety and intelligence level of the isolation system. The drive mode of the existing isolation valve has limited adaptability and often cannot meet the load requirements of multiple scenarios. For example, the hydraulic drive does not respond quickly enough when closing quickly, and other drive modes may not provide sufficient closing thrust. In addition, the system lacks multi-level safety protection in design, and does not provide an effective redundant protection mechanism for pressure mutations or equipment failures, thereby increasing the risk of system failure.

[0005] It can be seen that the prior art has the following problems:

[0006] (1) In critical applications such as nuclear power plants, traditional isolation valve systems have limited response speed and cannot quickly achieve isolation operations.

[0007] (2) Sealing reliability issues under high temperature and high pressure environments.

[0008] (3) Precise control of valve operation. To meet the needs of various working conditions, traditional valves lack precise control modes, which may lead to misoperation or delays.

[0009] (4) Safety isolation issues in high-pressure steam environments. Traditional isolation valves may fail due to sudden pressure changes in high-pressure steam conditions. Summary of the invention

[0010] The purpose of this application is to provide a nuclear power plant steam power supply rapid isolation valve, isolation system, and isolation method, which solves the problems in the prior art that the isolation valve has a slow response speed, poor operating stability, and cannot achieve rapid and reliable isolation in an emergency.

[0011] In order to achieve the above objectives, this application provides the following technical solutions:

[0012] In the first aspect, the present application provides a nuclear power plant steam-powered rapid isolation valve, comprising a valve body, a bracket and a gate assembly; the interior of the valve body is a circular central cavity and is provided with guide ribs, and the bottom of the valve body is provided with a boss; the bracket is detachably connected to the valve body; the gate assembly is installed at the end of the valve stem, and the gate assembly includes two gates, a gate frame arranged up and down between the two gates, and a lower wedge block, the gate frame moves along the wedge surface, and the lower wedge block moves along the flow direction.

[0013] In some embodiments, a set of position indicators are installed on the bracket, corresponding to the open position, the closed position and the 90% opening respectively.

[0014] In some embodiments, the position indicator is mounted on platforms on both sides of the window opening of the bracket.

[0015] In some embodiments, the bracket is a cylindrical structure with two symmetrical windows opened on the side wall.

[0016] In some embodiments, a valve cover is disposed on the valve body, and a stuffing box is disposed on the top of the valve cover.

[0017] In a second aspect, the present application provides a nuclear power plant steam energy supply rapid isolation system, comprising:

[0018] The nuclear power plant steam energy supply rapid isolation valve;

[0019] A gas-liquid driving device for controlling the travel action of the steam-powered rapid isolation valve of the nuclear power plant;

[0020] A connecting sleeve device, used to connect the output shaft of the gas-liquid drive device and the valve stem;

[0021] A sealing device for sealing the nuclear power plant steam powered rapid isolation valve;

[0022] Bypass device is used to prevent valve locking due to abnormal pressure increase in the middle chamber.

[0023] In some embodiments, the gas-liquid drive device has a quick closing function. In the quick closing operation, when the hydraulic system is started, the quickly released pressure drives the output rod and the valve stem through the piston, driving the valve stem and the gate assembly to move downward, quickly closing the valve and achieving sealing.

[0024] In some embodiments, the connecting sleeve device includes an upper connecting sleeve and a lower connecting sleeve which are arranged up and down. The upper connecting sleeve adopts a two-half structure, and the lower connecting sleeve is connected to the valve stem through a thread.

[0025] In some embodiments, the bypass device is a bypass valve. Under normal operating conditions, the bypass valve remains in a normally closed state. When manual intervention is required, the bypass valve can automatically switch states to achieve sealing of necessary parts and protect the valve from unexpected pressure fluctuations.

[0026] In a third aspect, the present application provides a method for rapid isolation of steam energy supply in a nuclear power plant, comprising:

[0027] Step 1: When the control system receives the condition that needs to be isolated, it automatically sends a command to the gas-liquid drive device;

[0028] Step 2: After the gas-liquid drive device receives the command, the hydraulic system of its A / B channel is quickly activated, the hydraulic oil flow inside the gas-liquid drive system is adjusted, and the rapid pressure relief process is started;

[0029] Step 3: The piston in the hydraulic cylinder starts to move in response to the pressure change, directly transmitting the force to the output rod, and then to the valve stem. After the hydraulic system is activated, the piston inside the system immediately responds to the pressure change and drives the valve stem to move downward;

[0030] Step 4: The gate assembly moves downward, and the downward movement of the valve stem drives the gate assembly to close. Under low-pressure conditions, the valve stem thrust is transmitted to the sealing surface through the wedge surface to form a forced seal. Under high-pressure conditions, the medium pressure automatically acts on the back of the gate to achieve automatic sealing;

[0031] Step 5: As the gate is completely fitted to the valve seat, the main sealing structure is activated to form a forced or automatic seal. Under low pressure, the valve stem thrust is transmitted to the sealing surface through the wedge surface to form a seal. Under high pressure, the medium pressure automatically pushes the back of the gate to enhance the sealing effect. The main sealing structure is a sealing mechanism composed of a gate assembly and a sealing surface. The mechanism uses the wedge surface structure to form a forced seal through the valve stem thrust under low pressure and automatically seals through the medium pressure under high pressure.

[0032] Step 6: Once the medium is completely isolated, the control system will monitor the status of the valve and reset the drive system as needed for reuse.

[0033] Compared with the prior art, the nuclear power plant steam energy supply rapid isolation valve, isolation system, and isolation method provided by the present application have the following beneficial effects:

[0034] This application can achieve fast and reliable isolation functions in key applications such as steam power supply in nuclear power plants, improving the safety and response efficiency of the system.

[0035] In the process of supplying high-temperature steam to nuclear power units, this application can quickly cut off the steam flow in an emergency, effectively preventing the accident from spreading to the chemical production line, thereby ensuring the production safety and continuity of the chemical plant. At the same time, the application of this application improves the safety scheduling capability of nuclear power units, so that when encountering systemic risks, the connection between the nuclear power plant and the external system can be immediately cut off to ensure the stable operation and nuclear safety of the nuclear power plant. The implementation of this technology has significantly enhanced the safety management level of cross-industry energy supply and provided reliable technical support for the safety coordination between nuclear power units and the chemical industry.

[0036] In view of the limited response speed of traditional isolation valve systems and the inability to quickly implement isolation operations, this application integrates a gas-liquid drive device to enable the valve to quickly respond to safety signals, achieve rapid closure and efficient isolation, and greatly improve the emergency response speed.

[0037] In view of the high temperature and high pressure conditions in the nuclear power environment, this application designs a multi-level sealing structure, including a W-type wedge-tight parallel double gate seal, which improves the sealing reliability of the valve. The main sealing surface is made of wear-resistant material to ensure long-term sealing under extreme working conditions and avoid the risk of sealing failure.

[0038] In view of the lack of precise control modes in traditional valves, which may lead to misoperation or delays, this application provides dual-mode control of slow opening / closing and fast closing, allowing flexible selection under different needs, ensuring that the valve can operate accurately and safely in both emergency and daily operations.

[0039] In view of the fact that traditional isolation valves may fail due to sudden pressure changes in high-pressure steam conditions, this application designs a bypass device and failure protection function to ensure that the high-pressure steam flow can still be isolated when the valve is locked or the pressure is abnormal, thereby preventing the accident from spreading.

[0040] This application integrates an advanced gas-liquid drive system, which can respond to safety signals or pressure anomalies in a short time and quickly start the closing operation. This rapid response is very critical for controlling high-pressure steam flow, and can isolate potential sources of danger at the early stage of an accident, greatly reducing safety risks.

[0041] The application incorporates complex control logic to allow the valve to operate in the most appropriate manner under different circumstances, whether in automatic or manual mode. This improves the accuracy of operation, ensuring that the valve is opened or closed in the correct manner when required, thereby improving the overall reliability of the system.

[0042] Furthermore, the present invention enhances the safety of the entire system by implementing multi-level safety logic, such as automatic operation of the bypass valve and valve failure safety lockout. These safety features ensure that the valve can be safely and effectively isolated before any possible system failure, preventing further expansion of the accident. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for the technical description.

[0044] Figure 1 A schematic diagram of the structure of the valve body provided for this application;

[0045] Figure 2 A schematic diagram of the structure of the valve cover provided for this application;

[0046] Figure 3 A schematic diagram of the structure of the support provided in this application;

[0047] Figure 4 A schematic diagram of the structure of the nuclear power plant steam energy supply rapid isolation valve connection device provided for this application;

[0048] Figure 5 A schematic diagram of the structure of the gate assembly device provided for this application;

[0049] Figure 6 Schematic diagram of the nuclear power plant steam power supply rapid isolation system provided for this application;

[0050] Figure 7 A flow chart of the lubricating oil level monitoring method provided in this application.

[0051] Description of reference numerals:

[0052] 1. Valve body; 2. Valve cover; 3. Position indicator; 4. Bracket; 5. Guide rib; 6. Boss; 7. Lifting ear; 8. Gate; 9. Gate frame; 10. Lower wedge; 11. Clamp ring. DETAILED DESCRIPTION

[0053] The following is further explained in detail through specific implementation methods.

[0054] like Figures 1 to 5 As shown, the present application provides a nuclear power plant steam-powered rapid isolation valve, comprising a valve body 1 , a valve cover 2 , a position indicator 3 and a bracket 4 .

[0055] like Figure 1 As shown, the valve body 1 is the core component of the nuclear power plant steam power supply rapid isolation valve. The interior of the valve body 1 is a circular middle cavity to ensure uniform stress distribution. The built-in guide rib 5 effectively positions the gate assembly to ensure the accuracy of operation. The boss 6 set on the bottom surface plays a limiting role when the valve is closed, increasing safety.

[0056] Preferably, there are two guide ribs 5 , which are arranged in parallel and are slender protruding structures.

[0057] The valve body 1 is connected to the valve seat by welding, and the connecting end of the valve is also a welding end, which ensures the sealing and durability of the valve under extreme working conditions.

[0058] The length of the valve body 1 is 1194 mm, and a reduced diameter design is adopted to optimize fluid flow and reduce stress concentration, thereby enhancing the stability of the overall structure.

[0059] The valve body 1 improves the operating efficiency and reliability of the valve through the above-mentioned combined design, and adapts to the stringent requirements in the nuclear power environment.

[0060] like Figure 2 As shown, the valve cover 2 has an axisymmetric structure, and a stuffing box is provided on the top, which effectively enhances the sealing ability of the valve and prevents leakage. Its lower end adopts an inverted sealing structure and is made of surfacing hard alloy, which not only improves corrosion resistance and wear resistance, but also ensures long-term durability under extreme pressure and temperature conditions.

[0061] The position indicator 3 is used to ensure that the operator can monitor and verify the status of the valve in real time. This valve design includes six position indicators 3, corresponding to the open position, closed position and 90% opening, and two indicators are equipped for each state. This redundant design improves the reliability and safety of the system. These position indicators 3 are installed on the platforms on both sides of the window opening of the bracket 4. The choice of position allows the operator to clearly observe the indication status from different perspectives, thereby achieving fast and accurate operation feedback.

[0062] The position indicator 3 realizes its function by mechanically connecting with the indicator rod on the valve stem. When the valve stem moves to the specified position, the corresponding indicator rod drives the position indicator to display the current position status. This direct mechanical response mechanism is the key to preventing misoperation and instant diagnosis, especially in emergency situations that require rapid response, ensuring the operating accuracy and response speed of the valve.

[0063] like Figure 3As shown, the bracket 4 adopts a bracket design of an integral casting process, which ensures the integrity and mechanical strength of the structure and provides a solid support foundation for the valve. The bracket 4 adopts a symmetrical window design, which optimizes the installation and maintenance path of the internal components and increases the accessibility and service efficiency of the structure. The bracket 4 has two symmetrical windows on the side wall, which are arranged vertically and have a rectangular shape, for example.

[0064] The bracket 4 adopts a cylindrical structure, and the cylindrical structure has undergone a detailed stress analysis to achieve uniform stress distribution, which is crucial to prevent stress concentration in a high-pressure operating environment.

[0065] The bracket 4 is provided with four lifting lugs 7, which are designed with consideration given to the mechanical balance of multi-point lifting, thus ensuring that the entire valve unit can be safely and effectively manipulated during the transportation and installation stages.

[0066] like Figure 4 As shown, the valve body 1 and the bracket 4 are connected by a clamp ring 11, and the protruding annular structures of the valve body 1 and the bracket 4 are buckled together. The outer diameters of the two annular structures are the same, and the clamp ring 11 is adapted to the annular structure through a concave structure and clamped together.

[0067] like Figure 5 As shown, the gate assembly device includes a gate 8, a gate frame 9, and a lower wedge 10, and the gate assembly device is connected to the end of the valve stem. The design and function of the gate assembly device directly affect the sealing effect and operational reliability of the valve. The gate assembly device adopts a double wedge parallel double gate structure, which optimizes the mechanical properties and sealing of the closing action. The gate assembly device includes two right-angle wedges configured up and down and two gates 8. These wedges and gates 10 are all designed with a single wedge surface. The wedge surface part is welded with hard alloy to increase the wear resistance and corrosion resistance, thereby improving the durability of the valve under harsh working conditions. When the valve approaches the closed position, the upper wedge moves along the wedge surface, while the lower wedge 10 only moves along the flow direction. This design ensures the accuracy and fluid dynamics efficiency of the valve when closing. In addition, a flexible connection is achieved between the gate assembly device and the valve stem, which allows a slight displacement in the flow direction during the operation of the valve, thereby reducing mechanical stress and adapting to the thermal expansion and contraction of the pipeline or installation errors.

[0068] In addition, if Figure 6 As shown, the present application also provides a nuclear power plant steam power supply rapid isolation system including the above-mentioned nuclear power plant steam power supply rapid isolation valve, a gas-liquid drive device, a connecting sleeve device, a sealing device and a bypass device.

[0069] The gas-liquid drive provides the valve with multi-mode operation capability and high response speed. The gas-liquid drive is designed to support precise control of the valve, including slow opening and closing, fast closing, and partial stroke action to adapt to different operating requirements and emergency situations. The gas-liquid drive adopts a dual-channel hydraulic system, which can start and adjust the pressure under the hydraulic cylinder in a very short time, thereby achieving rapid pressure relief. In the rapid closing operation, when the hydraulic system is started, the rapidly released pressure drives the output rod and the valve stem through the piston, driving the valve stem and gate assembly to move downward, quickly closing the valve and achieving effective sealing. This design not only improves the closing speed, but also ensures the reliable sealing and operational safety of the valve at critical moments through precise pressure and power control.

[0070] The connecting sleeve device includes an upper connecting sleeve and a lower connecting sleeve. The connecting sleeve device plays a connecting and transmission role in the steam energy supply of nuclear power plants. The connecting sleeve device adopts a two-axis connection structure to ensure the precise docking and firm connection between the output shaft of the gas-liquid drive device and the valve stem, thereby ensuring the reliability of operation and the response speed of the valve. The upper connecting sleeve adopts a two-half structure, which allows it to be easily installed on the T-head of the output shaft of the drive device. The lower connecting sleeve is connected to the valve stem through threads, providing a stable and reliable connection method. The two connecting sleeves are fastened by bolts to ensure the stability and durability of the entire connection device under high pressure and high stress conditions. In addition, the compact design of the upper and lower connecting sleeves optimizes the use of space and reduces the fluid power loss caused by the excessive size of the connection part. The bolts in the structure are subject to tensile stress. This design enhances the bearing capacity of the overall structure and avoids mechanical failure under extreme operating conditions.

[0071] The sealing device ensures the sealing and reliability of the valve under various pressure conditions. The sealing device adopts a multi-level and efficient sealing structure to cope with the harsh working conditions in nuclear power plants. First, the main seal adopts a W-type wedge-tight parallel double gate structure, including two parallel gates, and the valve seat is fixed to the valve body by welding. The gate sealing surface has a larger width than the valve seat sealing surface. This design helps to provide a larger contact area, thereby enhancing the sealing effect. The hard alloy is welded on the sealing surface, which not only enhances the wear resistance of the sealing surface, but also improves the durability of the overall structure. Under low-pressure conditions, the thrust of the valve stem is transmitted to the sealing surface through the wedge surface to form a forced seal; while under high-pressure conditions, the pressure of the medium directly acts on the back of the gate to achieve automatic sealing. In addition, the middle cavity seal adopts a self-tightening sealing structure, and the sealing performance increases accordingly with the increase of pressure. This is particularly suitable for environments with dynamic pressure changes, in which the sealing ring is made of flexible graphite material, which is selected for its excellent elasticity and high temperature resistance. The valve stem sealing structure adopts a packing structure, and a live-loaded packing structure and a reverse sealing structure are added. The live-loaded packing structure ensures sealing during stem movement, while the inverted seal structure provides additional sealing protection when the valve needs maintenance or overhaul.

[0072] The main purpose of setting up a bypass device is to prevent the valve from locking due to abnormal pressure increase in the middle chamber. The bypass valve adopts a DN15 three-way automatic reversing valve, which is consistent with the design parameters of the main valve to ensure the consistency and reliability of the overall system. Under normal operating conditions, the bypass valve remains in a normally closed state, which helps to maintain the stability and safety of the system. When manual intervention is required, such as opening the handwheel on the inlet side or the handwheel on the outlet side, the bypass valve can automatically switch states to achieve sealing of necessary parts and protect the valve from unexpected pressure fluctuations. In addition, the valve is also equipped with an internal sealing detection interface and a thread plug for regular detection and maintenance of the sealing performance of the bypass valve and the main valve. This design not only enhances the operational flexibility of the valve, but also greatly improves the system's safety response capability in the face of abnormal pressure.

[0073] Based on the above nuclear power plant steam supply rapid isolation valve and isolation system, such as Figure 7 As shown, the present application also provides a method for rapid isolation of steam energy supply in nuclear power plants, which can achieve rapid and reliable isolation functions in key applications such as steam energy supply in nuclear power plants, and improve the safety and response efficiency of the system. The details are as follows:

[0074] Step 1: Trigger command. When the gas-hydraulic drive system senses the condition that requires isolation, it will automatically send a command to the gas-hydraulic drive device. The gas-hydraulic drive system is equipped with a selection function that allows the operator to choose a fast or slow response mode as needed.

[0075] Step 2: Activate the gas-hydraulic drive. After the gas-hydraulic drive receives the command, the hydraulic system of its A / B channel is quickly activated. The hydraulic oil flow inside the system is adjusted to apply the required pressure change to the hydraulic cylinder, thereby starting the rapid pressure relief process.

[0076] The A / B channel hydraulic system of the gas-hydraulic drive is quickly activated after receiving the command for rapid isolation. The activation process involves precise regulation of the pressure below the hydraulic cylinder. This regulation is achieved through advanced hydraulic control technology, ensuring a quick response to changes in pressure. While the hydraulic system is activated, the control system controls the flow and volume of hydraulic oil to quickly reduce or adjust the pressure in the hydraulic cylinder. This pressure adjustment is precisely controlled by electronically controlled valves, allowing the rapid release or redirection of hydraulic oil flow, thereby achieving rapid pressure relief below the hydraulic cylinder. The purpose of rapid pressure relief is to drive the piston connected to the hydraulic system to move quickly, which is a key step in achieving rapid valve closing. The rapid movement of the piston requires a rapid reduction in pressure in the hydraulic cylinder, which can overcome any resistance or inertia in the system, ensuring that the valve can be closed quickly and safely in an emergency.

[0077] Step 3: Piston and output rod action. The piston in the hydraulic cylinder begins to move in response to the pressure change, and this action directly transmits the force to the output rod that is mechanically connected to it. The output rod further transmits the action to the valve stem, and since the two are tightly connected through a precisely designed connecting sleeve, this ensures synchronization and precision of the action.

[0078] When the hydraulic system is activated, a piston inside the system immediately responds to the pressure change. This piston, through the mechanical link connected to it, drives the output rod and the valve stem directly connected to it to move downward. This movement is achieved through a precision-designed connecting sleeve, which ensures a firm connection and a gap-free fit between the output rod and the valve stem.

[0079] The sleeve is specially designed to accommodate and support the direct force transmission between the output rod and the valve stem. It has high strength and durability to ensure that the power transmission between the two will not loosen or slip during the rapid operation of the valve, thus ensuring the synchronization and precision of the action.

[0080] Step 4: Action of the valve stem and gate assembly. As the valve stem moves downward, the gate assembly fastened to the end of the valve stem also moves downward accordingly. The gate assembly adopts a double wedge parallel double gate structure. The two wedge-shaped gates are closed along a predetermined trajectory under the push of the valve stem, and fit tightly on the valve seat through the mechanical wedging principle, thereby forming an effective fluid seal. The closing action is precisely controlled, and the positioning and movement of the gate achieve the best sealing effect due to the high synchronization of the connecting sleeve. The wedge design ensures that when the gate is close to the fully closed position, it can accurately fit the valve seat to achieve effective sealing.

[0081] The downward movement of the valve stem drives the gate assembly to close. The gate assembly consists of two wedges and two gates, which work together to make the closing action precise and effective. Under low-pressure conditions, the valve stem thrust is transmitted to the sealing surface through the wedge surface to form a forced seal; under high-pressure conditions, the medium pressure automatically acts on the back of the gate to achieve automatic sealing.

[0082] Step 5: Sealing and safety confirmation. As the gate is fully fitted to the valve seat, the main sealing structure is activated to form a forced or automatic seal, depending on the pressure conditions. At low pressure, the valve stem thrust is transmitted to the sealing surface through the wedge surface to form a seal; at high pressure, the medium pressure automatically pushes the back of the gate to enhance the sealing effect.

[0083] Step 6: System reset and monitoring. Once the medium is completely isolated, the control system will monitor the valve status and reset the gas-liquid drive system as needed for reuse. In addition, the system's built-in monitoring and diagnostic tools will continuously evaluate the performance of the valve to ensure that it is always in optimal working condition.

[0084] Once the isolation condition is removed or the safe state is restored as confirmed by the control system, the control system will reset the gas / hydraulic drive to prepare it for the next operating demand.

[0085] In addition, based on the above-mentioned nuclear power plant steam-powered rapid isolation valve and its use method, in order to ensure that the rapid isolation valve can reliably and quickly respond to emergencies in high-risk environments such as nuclear power plants, the present application also provides a logic control system for the nuclear power plant steam-powered rapid isolation valve. The following are the key logics used in the system, which are responsible for the control of different operating modes and safety mechanisms.

[0086] 1. The quick closing operation logic is as follows: The quick closing operation logic ensures that the valve can be quickly closed when any safety signal is detected or the system pressure exceeds the predetermined critical value:

[0087] CV=SS∨(P>PT)

[0088] Where:

[0089] CV: Close Valve;

[0090] SS:Safety Signal;

[0091] P:Pressure;

[0092] PT:Pressure Threshold

[0093] The logic is that if there is a safety signal or the pressure exceeds the set pressure threshold, the valve will be closed, which can respond to potential system overpressure or other emergency safety conditions and prevent the accident from spreading.

[0094] 2. Test mode operation logic

[0095] The test mode operating logic allows functional testing with normal system pressure and no safety warnings:

[0096]

[0097] Where:

[0098] TMO: Test Mode Operation

[0099] TC: Test Command

[0100] TMO is true if and only if the following conditions are met at the same time: TC is true, SS is true and (P≤PT) is true.

[0101] This mode is used to regularly check the responsiveness and sealing effect of the valve to ensure safe operation.

[0102] 3. Bypass valve operation logic

[0103] The bypass valve operation logic is activated when the pressure exceeds the normal operating range to protect the system from damage:

[0104] BVO=(P<LPL)∨(P>HPL)

[0105] Where:

[0106] BVO: Bypass Valve Operation

[0107] LPL: Low Pressure Limit

[0108] HPL: High Pressure Limit

[0109] The logic of the formula is that if the pressure P is lower than the low pressure limit LPL or higher than the high pressure limit HPL, the bypass valve will be operated. This means that the bypass valve is used to adjust the pressure of the system to ensure that it remains within a safe range. This function is essential to maintain system stability and prevent equipment failure due to abnormal pressure.

[0110] 4. Automatic and manual operation logic

[0111] Automatic and manual operation logic allows the operator to choose the control method according to the specific situation:

[0112]

[0113] Where:

[0114] VOM: Valve Operation Mode

[0115] AMC: Auto Mode Command

[0116] MMC: Manual Mode Command

[0117] MOR:Manual Override

[0118] Among them, (AMC∧ (MMC>MOR): When the automatic mode command is true and there is no manual override, the valve will enter the automatic operation mode. (MMC>MOR): If the manual mode command priority is higher than the manual override priority, the valve will enter the manual operation mode.

[0119] 5. Valve failure safety lock logic

[0120] When a serious error is detected in the system or the maximum pressure is exceeded, the valve fail-safe lockout will be activated:

[0121]

[0122] Where:

[0123] FSO: Failure Safety Override

[0124] MPT: Maximum Pressure Threshold

[0125] SE:System Error

[0126] The logic contained in this formula is: (P>MPT∧ (SE∧MOR): If the pressure exceeds the maximum pressure threshold and there is no manual override, this indicates that the system needs to automatically initiate a failsafe override to protect the system. (SE∧MOR): If a system error occurs and the manual override is activated, this also requires the failsafe override to be initiated.

[0127] This mechanism ensures that the fail-safe override can be activated in two cases:

[0128] (1) When the system pressure is too high and there is no manual intervention, fail-safe operation is automatically initiated to prevent potential danger.

[0129] (2) When a system error occurs and there is a manual override, fail-safe operation also needs to be activated, probably to ensure that more direct manual control intervention can be made in abnormal conditions.

[0130] The nuclear power plant steam-powered rapid isolation valve of the present application realizes real-time and accurate isolation of nuclear power plant steam flow by integrating sophisticated gas-liquid drive technology and complex control logic. In variable working environments, such as pressure fluctuations or activation of safety systems, isolation operations can still be performed quickly and accurately, significantly improving the speed and reliability of response.

[0131] In actual applications, when the valve's overall monitoring system detects a pressure change that exceeds the safety threshold, the valve's control system can be activated immediately to provide operators with critical system status information, supporting effective emergency response and equipment maintenance. This not only avoids the spread of accidents caused by delayed isolation, but also significantly reduces potential maintenance costs and downtime, and improves the operating efficiency of nuclear power plants.

[0132] In addition, the application of this application also helps to improve the dispatch flexibility and economy of the energy system, because it allows the safe and efficient management of the integration and conversion of multiple energy flows. This not only enhances the stability and reliability of the energy system, but also provides support for the diversification and sustainable development of the modern energy grid.

[0133] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed in the present application should be covered within the protection scope of the present application.

Claims

1. A nuclear power plant steam power supply rapid isolation valve, characterized in that: The invention comprises a valve body (1), a bracket (4) and a gate assembly; the interior of the valve body (1) is a circular central cavity and is provided with a guide rib (5); the bottom of the valve body (1) is provided with a boss (6); the bracket (4) is detachably connected to the valve body (1); the gate assembly is installed at the end of the valve stem, and the gate assembly comprises two gates (8), a gate frame (9) and a lower wedge block (10) arranged in an upper and lower configuration between the two gates (8); the gate frame (9) moves along the wedge surface, and the lower wedge block (10) moves along the flow channel direction.

2. The nuclear power plant steam powered rapid isolation valve according to claim 1, characterized in that: A set of position indicators (3) are installed on the bracket (4), corresponding to the open position, the closed position and the 90% opening respectively.

3. The nuclear power plant steam powered rapid isolation valve according to claim 2, characterized in that: The position indicator (3) is installed on platforms on both sides of the window opening of the bracket (4).

4. The nuclear power plant steam-powered rapid isolation valve according to claim 1, characterized in that: The support (4) is a cylindrical structure, and two symmetrical windows are provided on the side wall.

5. The nuclear power plant steam powered rapid isolation valve according to claim 1, characterized in that: The valve body (1) is provided with a valve cover (2), and the top of the valve cover (2) is provided with a stuffing box.

6. A nuclear power plant steam energy rapid isolation system, characterized in that: include: A nuclear power plant steam power supply rapid isolation valve as described in any one of claims 1 to 5; A gas-liquid driving device for controlling the travel action of the steam-powered rapid isolation valve of the nuclear power plant; A connecting sleeve device, used to connect the output shaft of the gas-liquid drive device and the valve stem; A sealing device for sealing the nuclear power plant steam powered rapid isolation valve; The bypass device is used to prevent the valve from locking due to abnormal pressure increase in the middle chamber.

7. The nuclear power plant steam energy rapid isolation system according to claim 6, characterized in that: The gas-liquid drive device has a quick closing function. In the quick closing operation, when the hydraulic system is started, the quickly released pressure drives the output rod and the valve stem through the piston, driving the valve stem and the gate assembly to move downward, quickly closing the valve and achieving sealing.

8. The nuclear power plant steam energy rapid isolation system according to claim 6, characterized in that: The connecting sleeve device comprises an upper connecting sleeve and a lower connecting sleeve which are arranged up and down. The upper connecting sleeve adopts a two-half structure, and the lower connecting sleeve is connected to the valve stem through a thread.

9. The nuclear power plant steam energy rapid isolation system according to claim 6, characterized in that: The bypass device is a bypass valve. Under normal working conditions, the bypass valve remains in a normally closed state. When manual intervention is required, the bypass valve can automatically switch states to achieve sealing of necessary parts and protect the valve from unexpected pressure fluctuations.

10. A method for rapid isolation of steam energy supply in a nuclear power plant, characterized in that: include: Step 1: When the control system receives the condition that needs to be isolated, it automatically sends a command to the gas-liquid drive device; Step 2: After the gas-liquid drive device receives the command, the hydraulic system of its A / B channel is activated, the hydraulic oil flow inside the gas-liquid drive system is adjusted, and the rapid pressure relief process is started; Step 3: After the gas-liquid drive system receives the command, its internal hydraulic system is activated, and the piston moves immediately under the drive of the pressure change, directly transmitting the hydraulic pressure to the output rod. The output rod continues to move downward and transmits the thrust to the valve stem, and finally drives the gate assembly to move in the closing direction of the wedge surface; Step 4: The gate assembly moves downward, and the downward movement of the valve stem drives the gate assembly to close. Under low-pressure conditions, the valve stem thrust is transmitted to the sealing surface through the wedge surface to form a forced seal. Under high-pressure conditions, the medium pressure automatically acts on the back of the gate to achieve automatic sealing; Step 5: As the gate is completely fitted to the valve seat, the main sealing structure is activated to form a forced or automatic seal. When the pressure is low, the valve stem thrust is transmitted to the sealing surface through the wedge surface to form a seal. When the pressure is high, the medium pressure automatically pushes the back of the gate to enhance the sealing effect. Step 6: The control system will monitor the valve status and reset the gas-hydraulic drive system as needed for reuse.

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