Modular assembly of high-pressure shutdown components for steam turbines and its inspection and testing methods

Abstract

This invention discloses a modular device for high-pressure shutdown assembly pipelines in steam turbines and its inspection and testing method. This modular device integrates multiple dispersed interfaces and functional components into independent integrated valve group modules through a modular design. Multiple integrated valve group modules are fixed in place by connecting plates, eliminating the need to rebuild support structures and adapting to existing installation environments, thus offering high installation convenience. Each integrated valve group module corresponds to a pressure tap of the high-pressure shutdown assembly, achieving clear functional zoning. This optimization and integration of multiple interfaces significantly reduces the number of sealing points, fundamentally lowering the probability of oil leakage. The inspection and testing method for this modular device covers the testing of the device's basic performance, flow path unobstructedness, shell pressure resistance, valve sealing performance, and overall sealing performance, providing strong assurance for the stable operation of the steam turbine safety system.

Description

Technical Field

[0001] This invention relates to the field of steam turbine safety system technology, and in particular to a modular device for high-pressure shutdown components of steam turbines and its inspection and testing method. Background Technology

[0002] The turbine shutdown assembly is a core component of the turbine safety system. By controlling the flow of high-pressure safety oil, it ensures rapid and reliable turbine shutdown under abnormal operating conditions, directly impacting the operational safety and stability of the generator set. Traditional turbine shutdown assemblies have a dense network of instrument and pipeline interfaces, numbering as many as 61, which presents several drawbacks in practical applications: First, poor sealing performance and a high risk of oil leakage. Repeated disassembly and maintenance in confined spaces easily cause wear on the sealing surfaces, leading to oil leakage, fluctuations in safety oil pressure, and in severe cases, triggering the protection system to shut down the turbine. Second, the maintenance process is complex and unreliable. Traditional maintenance relies on manual operation, making it difficult to ensure consistent sealing at each interface, resulting in significant safety hazards after long-term use. Third, maintenance efficiency is low. Frequent maintenance shutdowns not only affect continuous unit operation but also increase equipment wear and production costs. Furthermore, traditional designs cannot adapt to high-frequency disassembly and assembly requirements, further exacerbating the high maintenance costs. Currently, there is a lack of a modular device for the high-pressure shutdown assembly pipelines of turbines and its inspection and testing methods. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a modular device for the pipeline of a high-pressure shutdown component of a steam turbine and a method for its inspection and testing.

[0004] The technical solution adopted by the present invention to solve its technical problem is: to construct a modular device for the pipeline of a high-pressure shutdown component of a steam turbine, which includes multiple independent integrated valve group modules and a connecting plate. The multiple integrated valve group modules are installed on the connecting plate, and the connecting plate is fixed to the existing support on site. Each integrated valve group module is connected to the pressure tap of the high-pressure shutdown component, and each integrated valve group module is provided with a medium flow channel, a module main valve, an instrument primary valve, an instrument secondary valve, an oil inlet connector, an instrument connector, and a pressure measuring interface.

[0005] The medium flow channel is connected to the oil inlet connector, the module main valve, the instrument primary valve, the instrument secondary valve, and the instrument connector, and is used to deliver the pressure oil output by the high-pressure shut-off component;

[0006] The main valve of the module is used to control the overall on / off state of the corresponding integrated valve group module;

[0007] The primary valve and the secondary valve of the instrument are used to achieve graded isolation of the instrument branch;

[0008] The oil inlet connector is used to connect the integrated valve group module to the pressure tap of the high-pressure shut-off component to introduce pressurized oil.

[0009] The instrument connector is used to transmit pressure oil signals;

[0010] The pressure measurement interface is used for instrument calibration.

[0011] In some embodiments, the module main valve, the instrument primary valve, and the instrument secondary valve are all cartridge-type needle valves, and the module main valve, the instrument primary valve, and the instrument secondary valve are all installed on the integrated valve group module by means of threaded connection.

[0012] In some embodiments, both the oil inlet connector and the instrument connector are mounted on the integrated valve group module using a union-type connection, and a sealing ring is provided between the oil inlet connector and the instrument connector and the integrated valve group module.

[0013] In this embodiment, a method for inspecting and testing a modular device for high-pressure shutdown components of a steam turbine is also constructed. This method is used to inspect and test the aforementioned modular device for high-pressure shutdown components of a steam turbine, and includes the following steps:

[0014] S1. Basic module inspection: Perform external dimension inspection, channel inspection, chemical composition analysis, mechanical property analysis, and weld flaw detection on the integrated valve group module;

[0015] S2. Flow detection: Connect low-pressure compressed air to the integrated valve group module, open the valve inside the integrated valve group module, and check whether compressed air is blown out from the outlet end of the integrated valve group module.

[0016] S3. High-pressure housing pressure resistance test: Fully open the valve of the integrated valve group module, seal the outlet end of the integrated valve group module, connect the test pressure fluid to the inlet end of the integrated valve group module, start the hydrostatic hydraulic test bench to control the high-pressure resistance test pressure, and determine whether there is leakage in the housing and joints of the integrated valve group module.

[0017] S4. Valve stem high-pressure sealing test: Seal the outlet end of the integrated valve group module, connect the test pressure fluid through the inlet end of the integrated valve group module, start the hydrostatic hydraulic test bench to control the sealing test pressure, and close the internal valves of different outlets of the integrated valve group module in sequence. Determine whether there is leakage in the corresponding valve when the internal valves of different outlets are closed.

[0018] S5. Gas pressure sealing test: Using a gas cylinder, nitrogen is introduced into the inlet of the integrated valve group module and the entire integrated valve group module is immersed in water for a certain period of time to determine whether there is any leakage in all parts of the integrated valve group module.

[0019] S6. Low-pressure housing pressure resistance test: Fully open the valves of the integrated valve group module, seal the outlet end of the integrated valve group module, connect the inlet end of the integrated valve group module to the test pressure fluid, and use a hydrostatic hydraulic test bench to control the low-pressure resistance test pressure to determine whether there is leakage at the housing and joints of the integrated valve group module.

[0020] In some embodiments, step S1 includes:

[0021] S11. Use measuring tools to inspect the shape and interface dimensions of the integrated valve group module;

[0022] S12. Use an endoscope to inspect the medium flow channel of the integrated valve group module to ensure that the medium flow channel is clean and free of impurities;

[0023] S13. Analyze the chemical composition of the material of the main body of the integrated valve group module;

[0024] S14. Conduct mechanical performance testing on the main body of the integrated valve group module to verify its strength and toughness;

[0025] S15. Use PT flaw detection method to inspect the welds of the main body of the integrated valve group module.

[0026] In some embodiments, in step S2, the pressure of the low-pressure compressed air connected to the inlet of the integrated valve assembly module is 4 bar to 8 bar using an air gun.

[0027] In some embodiments, in step S3, the hydrostatic test bench is first started to control the sealing test pressure to 170 bar to 190 bar, and the pressure is held for 9 to 11 minutes to determine whether the corresponding valve has leakage. Then, the hydrostatic test bench is used to control the sealing test pressure to 350 bar to 370 bar, and the pressure is held for 14 to 16 seconds to determine whether the corresponding valve has leakage.

[0028] In some embodiments, in step S4, the hydrostatic test bench is first started to control the sealing test pressure to 120 bar to 140 bar, and the pressure is maintained for 9 to 11 minutes to determine whether the corresponding valve has leakage. Then, the hydrostatic test bench is used to control the sealing test pressure to 260 bar to 280 bar, and the pressure is maintained for 14 to 16 seconds to determine whether the corresponding valve has leakage.

[0029] In some embodiments, in step S5, the integrated valve module is connected to nitrogen gas at 38 bar to 42 bar and immersed in water for 9 to 11 seconds. Then, it is observed whether bubbles are generated in all parts of the integrated valve module to verify whether there is any leakage in all parts of the integrated valve module.

[0030] In some embodiments, the inspection and testing method further includes step S7, identification inspection: visually inspecting the identification of the integrated valve group module.

[0031] The implementation of this invention has the following beneficial effects: This modular device for the high-pressure shut-off assembly pipeline of a steam turbine integrates multiple dispersed interfaces and functional components into independent integrated valve group modules through modular design. Multiple integrated valve group modules are fixed and installed via connecting plates, eliminating the need to rebuild supports and adapting to the existing installation environment, thus offering high installation convenience. Each integrated valve group module corresponds to a pressure tap of the high-pressure shut-off assembly, achieving clear functional zoning. The integration and optimization of traditional multiple interfaces significantly reduces the number of sealing points, fundamentally lowering the probability of oil leakage. The main module valve can achieve overall on / off control of a single integrated valve group module. The primary and secondary instrument valves achieve hierarchical isolation of instrument branches. During maintenance, corresponding valves can be selectively closed without overall shutdown, supporting partial maintenance, greatly improving maintenance efficiency, reducing unit downtime, and lowering production costs. The pressure measurement interface provides a convenient channel for instrument calibration, allowing calibration work to be completed without disassembling pipelines, further improving operation and maintenance convenience, while ensuring the accuracy of pressure oil signal transmission and enhancing equipment reliability. Attached Figure Description

[0032] To more clearly illustrate the technical solution of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort. In the drawings:

[0033] Figure 1 This is a schematic diagram of the integrated valve group module in some embodiments of the present invention;

[0034] Figure 2 This is a schematic diagram of the overall structure of the turbine high-pressure shutdown component pipeline modular device in some embodiments of the present invention. Detailed Implementation

[0035] To provide a clearer understanding of the technical features, objectives, and effects of this invention, specific embodiments are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the orientations or positional relationships indicated by terms such as "front," "rear," "upper," "lower," "left," "right," "longitudinal," "horizontal," "vertical," "horizontal," "top," "bottom," "inner," "outer," "head," and "tail" are based on the orientations or positional relationships shown in the accompanying drawings, and are constructed and operated in a specific orientation. They are only for the convenience of describing this technical solution and do not indicate that the device or element referred to must have a specific orientation; therefore, they should not be construed as limitations on this invention.

[0036] It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "linking," "fixing," and "setting" 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. When an component is referred to as being "on" or "below" another component, the component can be located "directly" or "indirectly" on the other component, or there may be one or more intermediary components. The terms "first," "second," "third," etc., are only for the convenience of describing this technical solution and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," "third," etc., may explicitly or implicitly include one or more of that feature. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0037] Please see Figure 1 and Figure 2 This is a modular device for the pipeline of a high-pressure shutdown component of a steam turbine, which includes multiple independent integrated valve group modules 1 and a connecting plate 2. The multiple integrated valve group modules 1 are installed on the connecting plate 2, and the connecting plate 2 is fixed to the existing bracket 3 on site. Each integrated valve group module 1 is connected to the pressure tap of the high-pressure shutdown component, and each integrated valve group module 1 is provided with a medium flow channel, a module main valve 11, an instrument primary valve 12, an instrument secondary valve 13, an oil inlet connector 14, an instrument connector 15, and a pressure measuring interface 16. The medium flow channel is connected to the oil inlet connector 14, module main valve 11, instrument primary valve 12, instrument secondary valve 13, and instrument connector 15 to deliver the pressure oil output by the high-pressure shutdown component; the module main valve 11 is used to control the overall on / off state of the corresponding integrated valve group module 1; the instrument primary valve 12 and instrument secondary valve 13 are used to achieve graded isolation of the instrument branches; the oil inlet connector 14 is used to connect the integrated valve group module 1 and the pressure tap of the high-pressure shutdown component to introduce pressure oil; the instrument connector 15 is used to transmit pressure oil signals; and the pressure measurement interface 16 is used for instrument calibration.

[0038] Specifically, the main valve 11 is used to control the overall on / off state of the corresponding integrated valve group module 1, realizing independent start / stop control of a single integrated valve group module 1; the instrument primary valve 12 and the instrument secondary valve 13 work together to realize the hierarchical isolation of the instrument branches, ensuring system safety during instrument maintenance; the oil inlet connector 14 is used to connect the integrated valve group module 1 to the pressure tap of the high-pressure shutdown component, realizing the stable introduction of high-pressure safety oil; the instrument connector 15 is used to transmit the pressure oil signal to the external monitoring instrument, providing data support for the system operating status; the pressure measuring interface 16 is used to connect to the calibration equipment to perform accuracy calibration of the instrument, and the calibration operation can be completed without disassembling the pipeline.

[0039] Understandably, this modular device for the turbine high-pressure shutdown assembly pipeline integrates multiple dispersed interfaces and functional components into an independent integrated valve group module 1 through modular design. Multiple integrated valve group modules 1 are installed and fixed by connecting plates 2, eliminating the need to rebuild the support structure, adapting to the existing installation environment, and offering high installation convenience. Each integrated valve group module 1 corresponds to a pressure tap of the high-pressure shutdown assembly, achieving clear functional zoning. By integrating and optimizing the traditional multiple interfaces, the number of sealing points is significantly reduced, fundamentally lowering the probability of oil leakage. The module master valve 11 can realize the overall on / off of a single integrated valve group module 1, while the instrument primary valve 12 and instrument secondary valve 13 achieve hierarchical isolation of instrument branches. During maintenance, corresponding valves can be closed selectively without overall shutdown, supporting partial maintenance, greatly improving maintenance efficiency, reducing unit downtime, and lowering production costs. The pressure measurement interface 16 provides a convenient channel for instrument calibration, allowing calibration work to be completed without disassembling the pipeline, further improving operation and maintenance convenience, while ensuring the accuracy of pressure oil signal transmission and enhancing the reliability of equipment operation.

[0040] In a specific embodiment, the integrated valve group module 1 comprises three modules: module A, module B, and module C, all mounted on the same connecting plate 2. The integrated valve group module 1 is generally rectangular in shape. The oil inlet connector 14 is located below the integrated valve group module 1, the instrument connector 15 is located above the integrated valve group module 1, and the module main valve 11 and the instrument primary valve 12 are located on the front panel of the integrated valve group module 1. The integrated valve group module 1 has a media flow channel with an inner diameter of Φ5mm. The main components of the integrated valve group module 1 are made of 304 stainless steel forgings. The valves of the integrated valve group module 1, the valve core, and the valve seat all use a metal hard seal for easy maintenance and repair. The valve seat is integrally machined within the integrated valve group module 1.

[0041] Furthermore, the main valve 11, the primary instrument valve 12, and the secondary instrument valve 13 are all cartridge-type needle valves, and are all installed on the integrated valve assembly module 1 via threaded connections. Cartridge-type needle valves are characterized by their compact structure, good sealing performance, and high adjustment accuracy, making them suitable for the modular design requirements of the integrated valve assembly module 1. Direct installation on the integrated valve assembly module 1 via threaded connections ensures a strong connection, convenient disassembly and assembly, and facilitates future maintenance and replacement.

[0042] Both the oil inlet connector 14 and the instrument connector 15 are installed on the integrated valve group module 1 using a union-type connection. Sealing rings are provided between the oil inlet connector 14 and the instrument connector 15 and the integrated valve group module 1. The union-type installation of the oil inlet connector 14 and the instrument connector 15 greatly simplifies the disassembly and assembly process between the connectors and the integrated valve group module 1. During maintenance or replacement of the connectors, it is not necessary to disassemble other related components, reducing maintenance difficulty and labor intensity. The sealing rings further enhance the sealing performance between the connectors and the integrated valve group module 1, effectively preventing pressure oil leakage. Combined with the structural characteristics of the union-type installation, it can maintain a good sealing effect even after multiple disassemblies and reassemblies, adapting to the requirements of high-frequency disassembly and reassembly conditions. Specifically, the internal conical seal of the oil inlet connector 14 uses an O-ring, and the front face seal of the oil inlet connector 14 uses a trapezoidal ring.

[0043] In this embodiment, a method for inspecting and testing a modular device for high-pressure shutdown components of a steam turbine is also constructed. This method is used to inspect and test the aforementioned modular device for high-pressure shutdown components of a steam turbine, and includes the following steps:

[0044] S1. Module basic inspection: Perform external dimension inspection, channel inspection, chemical composition analysis, mechanical property analysis and weld flaw detection on integrated valve group module 1;

[0045] S2. Flow detection: Connect low-pressure compressed air to the integrated valve group module 1, open the internal valve of the integrated valve group module 1, and check whether compressed air is blown out from the outlet end of the integrated valve group module 1 to confirm that the medium flow channel of the integrated valve group module 1 is unobstructed and free of impurities.

[0046] S3. High-pressure housing pressure resistance test: Fully open the valve of integrated valve group module 1, seal the outlet end of integrated valve group module 1, connect the inlet end of integrated valve group module 1 to the test pressure fluid, start the hydrostatic hydraulic test bench to control the high-pressure resistance test pressure, and determine whether there is leakage in the housing and joints of integrated valve group module 1.

[0047] S4. Valve stem high-pressure sealing test: Seal the outlet end of the integrated valve group module 1, connect the test pressure fluid through the inlet end of the integrated valve group module 1, start the hydrostatic hydraulic test bench to control the sealing test pressure, and close the internal valves of different outlets of the integrated valve group module 1 in sequence. Determine whether there is leakage in the corresponding valve when the internal valves of different outlets are closed.

[0048] S5. Gas pressure sealing test: Using a gas cylinder, nitrogen is introduced into the inlet of the integrated valve module 1 and the entire integrated valve module 1 is immersed in water for a certain period of time to determine whether there is any leakage in all parts of the integrated valve module 1.

[0049] S6. Low-pressure housing pressure resistance test: Fully open the valve of integrated valve group module 1, seal the outlet end of integrated valve group module 1, connect the inlet end of integrated valve group module 1 to the test pressure fluid, use a hydrostatic hydraulic test bench to control the low-pressure resistance test pressure, and determine whether there is leakage at the housing and joints of integrated valve group module 1.

[0050] The inspection and testing methods for this modular turbine high-pressure shutdown assembly pipeline cover the basic performance, flow path unobstructedness, shell pressure resistance, valve sealing performance, and overall sealing performance. Basic module testing ensures the structural and material quality of the device; flow path testing ensures the medium flow path is free of impurities and blockages, preventing interference with valve operation; high-pressure shell pressure resistance testing verifies the pressure resistance and sealing capability of the shell and joints under high-pressure conditions; high-pressure valve stem sealing tests precisely test the sealing reliability of the valves at each outlet of the integrated valve group module 1; pneumatic sealing tests further identify and address any deficiencies, verifying overall sealing performance; and low-pressure shell pressure resistance testing verifies the stability of the device under long-term operating pressure. This comprehensive testing method is logically rigorous and progressively advanced, enabling thorough investigation of potential hazards and ensuring that all performance indicators meet standards after the device is put into use, providing strong support for the stable operation of the turbine's safety system.

[0051] Step S1 includes:

[0052] S11. Use measuring tools to inspect the shape and interface dimensions of the integrated valve group module 1;

[0053] S12. Use an endoscope to inspect the medium flow channel of the integrated valve group module 1 to ensure that the medium flow channel is clean and free of impurities;

[0054] S13. Analyze the chemical composition of the material of the main body of the integrated valve group module 1.

[0055] S14. Conduct mechanical performance testing on the main body of the integrated valve group module 1 to verify its strength and toughness;

[0056] S15. Use PT flaw detection method to inspect the welds of the main body of the integrated valve group module 1.

[0057] In a specific embodiment, S11, according to the valve group size inspection table, use measuring tools such as calipers and rulers to fully inspect the external dimensions and interface dimensions of the main body of the integrated valve group module 1 to ensure that all dimensional parameters meet the drawing requirements.

[0058] S12. According to the valve group size inspection table, insert the endoscope into the medium flow channel of the integrated valve group module 1 to ensure that the inside of the medium flow channel is clean and free of oil, metal debris and other impurities.

[0059] S13. Based on the chemical composition analysis report, the chemical composition of the material of the integrated valve module 1 is tested using a spectrometer and other relevant chemical instruments to confirm that the material composition is consistent with the design requirements.

[0060] S14. Based on the mechanical performance test report, tensile test and impact test are carried out on the main body of the integrated valve group module 1 to verify that its strength, toughness and other mechanical indicators meet the design standards.

[0061] S15. Based on the PT flaw detection report, conduct a comprehensive inspection of all welds of the integrated valve group module 1 using the PT flaw detection method. The inspection standard shall not be lower than NB / T47013.5 Class II or similar standards to ensure that the welds are free from defects such as cracks and porosity.

[0062] Understandably, dimensional checks are performed using measuring tools to ensure the module's shape and interface dimensions meet the drawing requirements, guaranteeing installation compatibility. Endoscopic inspection is used for channel inspection, allowing direct observation of the cleanliness of the media flow channels and preventing impurities from affecting device operation. Chemical composition analysis ensures that the material of integrated valve module 1 meets design standards, guaranteeing its high-pressure resistance, corrosion resistance, and other properties. Mechanical performance testing verifies the strength and toughness of integrated valve module 1, ensuring it can withstand pressure and vibration during operation. Weld flaw detection uses PT (Potential Transformer) testing to strictly control weld quality and prevent leakage or structural failure due to weld defects. These detailed testing steps work together to comprehensively ensure the basic quality of integrated valve module 1, laying a solid foundation for subsequent performance tests and actual operation.

[0063] In step S2, the inlet of the integrated valve assembly module 1 is purged with an air gun, and the pressure of the low-pressure compressed air is between 4 bar and 8 bar. This pressure range effectively removes residual impurities without damaging the internal valves or sealing structure of the integrated valve assembly module 1 due to excessive pressure; the pressure parameter setting is scientifically reasonable. Simultaneously, purging the inlet with an air gun creates a stable airflow within the flow channel, ensuring comprehensive detection of flow channel patency and accurate determination of any blockage. Specifically, in step S2, the inlet of the integrated valve assembly module 1 is purged with an air gun, using low-pressure compressed air at 6 bar. The internal valves, including the module main valve 11, instrument primary valve 12, and instrument secondary valve 13, are opened. By determining whether stable compressed air is being blown out from the outlet of the integrated valve assembly module 1, it is confirmed that the medium flow channel is unobstructed and free of blockage.

[0064] In step S3, the hydrostatic hydraulic test bench is first activated, and the sealing test pressure is controlled at 170 bar to 190 bar for 9 to 11 minutes to determine if the corresponding valves leak. Then, the hydrostatic hydraulic test bench is used to control the sealing test pressure at 350 bar to 370 bar for 14 to 16 seconds to determine if the corresponding valves leak again. The pressure range of 170 bar to 190 bar corresponds to approximately 1.1 times the maximum operating pressure of the device, and the 9 to 11 minute holding time can fully verify the sealing stability of the housing and joints of the integrated valve module 1 under normal high-pressure conditions. The pressure range of 350 bar to 370 bar corresponds to approximately 1.1 times the maximum design pressure, and the 14 to 16 second holding time can test the pressure resistance of the device under extreme high-pressure environments. The phased pressure testing and reasonable holding time settings simulate the actual operation and extreme conditions of the device, and ensure sufficient safety redundancy through moderate overpressure testing. This allows for a comprehensive investigation of potential leakage hazards in the housing and joints, ensuring the safety and reliability of the device under high-pressure environments. In a specific embodiment, all valves of the integrated valve group module 1 are fully opened, the outlet end is sealed tightly with a special sealing component, and hydraulic oil is connected to the inlet end as the test fluid. The hydrostatic hydraulic test bench is started, and the pressure is first increased to 180 bar and held for 10 minutes to determine if there is any leakage at the housing and joints of the integrated valve group module 1. Then, the pressure is increased to 360 bar and held for 15 seconds to again determine the sealing status of the housing and joints. No leakage indicates it is qualified. Alternatively, to determine if a corresponding valve is leaking, pressure changes can be recorded using a pressure sensor. An abnormal drop in pressure indicates leakage at the corresponding valve. This method can also be used to determine if the following valves are leaking, and will not be elaborated further here.

[0065] In step S4, the hydrostatic hydraulic test bench is first activated, and the sealing test pressure is controlled at 120 bar to 140 bar, held for 9 to 11 minutes, to determine if the corresponding valve leaks. Then, the hydrostatic hydraulic test bench is used to control the sealing test pressure at 260 bar to 280 bar, held for 14 to 16 seconds, to determine if the corresponding valve leaks again. The pressure range of 120 bar to 140 bar is suitable for the sealing test requirements of the valve and valve stem under normal operating pressure, and the holding time of 9 to 11 minutes can fully verify the sealing stability of the valve and valve stem under normal operating conditions. The pressure range of 260 bar to 280 bar corresponds to the ultimate operating pressure of the valve and valve stem, and the holding time of 14 to 16 seconds can test the sealing ability of the valve and valve stem under extreme pressure. By sequentially closing different outlet valves for targeted testing, valves and valve stems with poor sealing performance can be accurately located, avoiding the omission of hidden dangers caused by overall testing. In a specific embodiment, the outlet end of the integrated valve group module 1 is kept blocked, while the inlet end is continuously connected to the test fluid. Start the hydrostatic hydraulic test bench, first raise the pressure to 132 bar, hold the pressure for 10 minutes, then close the internal valves of different outlets in sequence, and determine whether there is any leakage in the corresponding valves; then raise the pressure to 270 bar, hold the pressure for 15 seconds, repeat the above operation of closing the valves, and determine the sealing condition of each valve again. If there is no leakage, it is qualified.

[0066] In step S5, nitrogen gas at 38 bar to 42 bar is introduced into the integrated valve module 1 and it is immersed in water for 9 to 11 seconds. The presence of bubbles is then observed in all parts of the integrated valve module 1 to verify whether there is any leakage. The nitrogen pressure range for the pneumatic sealing test is 38 bar to 42 bar. This pressure value can effectively detect minute leaks without damaging the device. Immersing the module in water for 9 to 11 seconds and observing the formation of bubbles to determine if there is leakage is a direct, sensitive, and easy-to-operate method that can quickly and accurately verify the overall sealing performance of the device. In a specific embodiment, 40 bar of nitrogen gas is introduced into the inlet of the integrated valve module 1 using a gas cylinder, all valves are closed, and the entire module is immersed in water for 10 seconds. The presence of bubbles in all parts of the integrated valve module 1 is then checked; no bubbles indicate that the overall sealing performance is qualified.

[0067] In step S6, in a specific embodiment, all valves of the integrated valve group module 1 are fully opened, the outlet is blocked, and the inlet is connected to the filtered test pressure fluid. The pressure is raised to 120 bar using a hydrostatic hydraulic test bench and held for 48 hours. During the pressure holding process, the pressure value is recorded every 6 hours to determine whether there is leakage at the shell and joints. If the pressure remains stable and there are no abnormalities, it is considered qualified.

[0068] The inspection and testing method also includes step S7, label inspection: The labeling of the integrated valve assembly module 1 is inspected visually. The labeling on the integrated valve assembly module 1 body is verified visually to ensure consistency with the assembly drawings. Labeling, as important product identification information, contains key information such as product model, serial number, and specifications. Accurate labeling ensures product traceability and facilitates accurate product identification during installation, maintenance, and repair, avoiding installation compatibility issues or maintenance errors due to incorrect labeling. In a specific embodiment, the labeling of the integrated valve assembly module 1 is randomly inspected visually to verify whether the product model, serial number, specifications, and other information on the label are consistent with the assembly drawings. If discrepancies are found, a comprehensive re-inspection of the entire batch of modules is conducted.

[0069] In practical applications, this modular device for the turbine high-pressure shutdown assembly pipeline optimizes and integrates the turbine high-pressure shutdown assembly pipeline, reducing the traditional 61 interfaces to 6. This significant reduction in interface number significantly lowers the risk of oil leakage. Furthermore, standardized component selection and installation methods improve sealing reliability and ease of disassembly and assembly. A comprehensive and systematic inspection and testing method ensures that all performance parameters of the device meet standards, greatly shortening maintenance time and supporting partial maintenance without shutting down the system. This invention has been successfully applied to multiple units within the group and has the potential for widespread application in nuclear power plants. It effectively reduces equipment maintenance costs, improves the safety and stability of generator unit operation, and has significant economic and social benefits.

[0070] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made with respect to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A method for inspecting and testing a modular device for a high-pressure shutdown component pipeline of a steam turbine, which is used to inspect and test the modular device for a high-pressure shutdown component pipeline of a steam turbine. The modular device for a high-pressure shutdown component pipeline of a steam turbine includes multiple independent integrated valve group modules (1) and a connecting plate (2). Multiple integrated valve group modules (1) are installed on the connecting plate (2). The connecting plate (2) is fixed to the existing bracket (3) on site. Each integrated valve group module (1) is connected to the pressure tap of the high-pressure shutdown component. Each integrated valve group module (1) is provided with a medium flow channel, a module main valve (11), an instrument primary valve (12), an instrument secondary valve (13), an oil inlet connector (14), an instrument connector (15), and a pressure measuring interface (16). The medium flow channel is connected to the oil inlet connector (14), the module main valve (11), the instrument primary valve (12), the instrument secondary valve (13), and the instrument connector (15) to deliver the pressure oil output by the high-pressure shutdown component; the module main valve (11) is used to control the overall on / off state of the corresponding integrated valve group module (1); the instrument primary valve (12) and the instrument secondary valve (13) are used to realize the graded isolation of the instrument branch; the oil inlet connector (14) is used to connect the integrated valve group module (1) and the pressure tap of the high-pressure shutdown component to realize the introduction of pressure oil; the instrument connector (15) is used to realize the transmission of pressure oil signal; the pressure measuring interface (16) is used for instrument calibration. Its features are, The inspection and testing method includes the following steps: S1. Module basic inspection: Perform external dimension inspection, channel inspection, chemical composition analysis, mechanical property analysis and weld flaw detection on the integrated valve group module (1); S2, Flow detection: Connect low-pressure compressed air to the integrated valve group module (1), open the internal valve of the integrated valve group module (1), and check whether compressed air is blown out from the outlet end of the integrated valve group module (1); S3, High pressure shell pressure test: Fully open the valve of the integrated valve group module (1), seal the outlet end of the integrated valve group module (1), connect the test pressure liquid to the inlet end of the integrated valve group module (1), start the hydrostatic test bench to control the high pressure test pressure, and determine whether there is leakage in the shell and joint of the integrated valve group module (1). S4. Valve stem high-pressure sealing test: Block the outlet end of the integrated valve group module (1), connect the test pressure liquid through the inlet end of the integrated valve group module (1), start the hydrostatic hydraulic test bench to control the sealing test pressure, and close the internal valves of different outlets of the integrated valve group module (1) in sequence. Determine whether there is leakage in the corresponding valve when the internal valves of different outlets are closed. S5. Gas pressure sealing test: Using a gas cylinder, nitrogen gas is introduced into the inlet of the integrated valve group module (1) and the integrated valve group module (1) is immersed in water for a certain period of time to determine whether there is any leakage in all parts of the integrated valve group module (1). S6. Low-pressure housing pressure resistance test: Fully open the valve of the integrated valve group module (1), seal the outlet end of the integrated valve group module (1), connect the inlet end of the integrated valve group module (1) to the test pressure liquid, use the hydrostatic hydraulic test bench to control the low-pressure pressure resistance test pressure, and determine whether there is leakage in the housing and joint of the integrated valve group module (1).

2. The inspection and testing method for the modular device of the turbine high-pressure shutdown assembly pipeline according to claim 1, characterized in that, Step S1 includes: S11. Use measuring tools to inspect the shape and interface dimensions of the integrated valve group module (1); S12. Use an endoscope to inspect the medium flow channel of the integrated valve group module (1) to ensure that the medium flow channel is clean and free of impurities; S13. Analyze the chemical composition of the material of the main body of the integrated valve module (1); S14. Perform mechanical performance testing on the main body of the integrated valve group module (1) to verify its strength and toughness; S15. The weld seams of the main body of the integrated valve group module (1) are inspected using the PT flaw detection method.

3. The inspection and testing method for the modular device of the turbine high-pressure shutdown assembly pipeline according to claim 1, characterized in that, In step S2, the pressure of the low-pressure compressed air connected to the inlet of the integrated valve group module (1) is 4 bar to 8 bar using an air gun.

4. The inspection and testing method for the modular device of the turbine high-pressure shutdown assembly pipeline according to claim 1, characterized in that, In step S3, the hydrostatic test bench is first started to control the sealing test pressure to 170 bar to 190 bar and hold the pressure for 9 to 11 minutes to determine whether the corresponding valve has leakage. Then, the hydrostatic test bench is used to control the sealing test pressure to 350 bar to 370 bar and hold the pressure for 14 to 16 seconds to determine whether the corresponding valve has leakage.

5. The inspection and testing method for the modular device of the turbine high-pressure shutdown assembly pipeline according to claim 1, characterized in that, In step S4, the hydrostatic hydraulic test bench is first started to control the sealing test pressure to 120 bar to 140 bar and hold the pressure for 9 to 11 minutes to determine whether the corresponding valve has leakage. Then, the hydrostatic hydraulic test bench is used to control the sealing test pressure to 260 bar to 280 bar and hold the pressure for 14 to 16 seconds to determine whether the corresponding valve has leakage.

6. The inspection and testing method for the modular device of the turbine high-pressure shutdown assembly pipeline according to claim 1, characterized in that, In step S5, the integrated valve module (1) is connected to nitrogen gas at 38 bar to 42 bar and immersed in water for 9 to 11 seconds. Then, observe whether bubbles are generated in all parts of the integrated valve module (1) to verify whether there is any leakage in all parts of the integrated valve module (1).

7. The inspection and testing method for the modular device of the turbine high-pressure shutdown assembly pipeline according to claim 1, characterized in that, The inspection and testing method also includes step S7, identification inspection: visual inspection of the identification of the integrated valve group module (1) is carried out.

8. The inspection and testing method for the modular device of the turbine high-pressure shutdown assembly pipeline according to claim 1, characterized in that, The module main valve (11), the instrument primary valve (12), and the instrument secondary valve (13) are all cartridge needle valves, and the module main valve (11), the instrument primary valve (12), and the instrument secondary valve (13) are all installed on the integrated valve group module (1) with threaded connection.

9. The inspection and testing method for the modular device of the turbine high-pressure tripping assembly pipeline according to claim 1, characterized in that, The oil inlet connector (14) and the instrument connector (15) are both installed on the integrated valve group module (1) in a union-type manner, and a sealing ring is provided between the oil inlet connector (14) and the instrument connector (15) and the integrated valve group module (1).

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