PLANT RELIABILITY EVALUATION SYSTEM, PLANT RELIABILITY EVALUATION METHOD, AND PLANT RELIABILITY EVALUATION PROGRAM

Abstract

To enhance reliability of apparatus through in-service inspections.SOLUTION: A plant reliability evaluation system S comprises: a detection unit 511 for detecting environmental information of a plant P in operation; and a soundness monitoring unit 514 configured to continuously monitor the soundness of apparatuses constituting the plant P on the basis of the environmental information of the operating plant during operation and importance information on the apparatuses constituting the plant P.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a plant reliability evaluation system, a plant reliability evaluation method, and a plant reliability evaluation program. [Background technology]

[0002] Maintenance methods based on system and component reliability are required for nuclear facilities such as nuclear power plants, Fukushima decommissioning, and reprocessing facilities.

[0003] Patent Document 1 describes an invention for a facility management support system that is expected to enable highly convenient operation by reviewing template contents. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-189088 A Summary of the Invention [Problem to be solved by the invention]

[0005] The method used in the United States has the problem that it requires a long period of time and a large amount of resources to evaluate the deterioration of systems and equipment based on the results of in-service inspections (ISI).

[0006] The U.S. Reactor Oversight Process (ROP), which the Nuclear Regulatory Commission referred to after the earthquake, requires constant monitoring of the integrity of the entire nuclear power plant. For operation beyond 40 years, constant monitoring of the reliability of not only conventional equipment but also large structures such as structural materials and weld lines is necessary.

[0007] Therefore, the present invention aims to improve the equipment reliability (ER) of not only conventional equipment but also large structures such as structural materials and weld lines by simultaneously utilizing in-service inspections and operating parameters of nuclear equipment. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the present invention provides a plant reliability evaluation system, comprising: an electrochemical corrosion potential sensor for measuring an electrochemical corrosion potential in the water chemistry of a lower plenum region of a nuclear reactor; The sampling pipe is connected to the drain pipe. Measure hydrogen concentration in reactor water 1. a water quality measuring device and a dose rate monitor for measuring a dose rate in the piping of the reactor; A memory unit that stores the composition of materials constituting the reactor, deterioration data of the materials, and inspection results; The corrosion potential, the hydrogen concentration, and the dose rate, which are environmental information of a plant in operation, and information on the importance of the equipment constituting the plant. , the material composition, the material degradation data, the inspection results a health monitoring unit that constantly monitors the health of the equipment constituting the plant based on the above, and instructs preventive maintenance of the equipment based on a result of the health evaluation of the equipment during operation by the health monitoring unit; Corrosion potential While monitoring the In the lower plenum area The amount of hydrogen injected into the feed water of the reactor by the hydrogen injection device is adjusted so that the corrosion potential is reduced to a target value; The measurement results from the first water quality measuring device A preventive maintenance unit that adjusts a hydrogen concentration in reactor water of the nuclear reactor; a life cycle management unit that develops a repair plan for the plant based on preventive maintenance instructions for corrosion of equipment by the preventive maintenance unit and on the results of the equipment health evaluation by the health monitoring unit; Equipped with.

[0009] The method for evaluating reliability of a plant of the present invention includes the steps of: measuring a corrosion potential in a water chemistry in a lower plenum region of a nuclear reactor by using an electrochemical corrosion potential sensor; 1. The water quality measuring device is The sampling pipe is connected to the drain pipe. A step of measuring a hydrogen concentration in reactor water, and a step of measuring a dose rate in a piping of the reactor by a dose rate monitor; A step in which a memory unit stores a material composition constituting the reactor, deterioration data of the material, and an inspection result; The health monitoring unit monitors the corrosion potential, the hydrogen concentration, and the dose rate, which are environmental information of the plant during operation, and the importance of the equipment constituting the plant. information, material composition, material degradation data, inspection resultsa step of constantly monitoring the health of the equipment constituting the plant based on the result of the health evaluation of the equipment during operation by the health monitoring unit, and a step of a preventive maintenance unit instructing preventive maintenance of the equipment; Corrosion potential While monitoring the In the lower plenum area adjusting the amount of hydrogen injected by a hydrogen injection device into the feedwater of the reactor so that the corrosion potential is reduced to a target value; The measurement results of the first water quality measuring device In the reactor water Water adjusting the concentration of the element; A life cycle management unit develops a repair plan for the plant based on a preventive maintenance instruction for corrosion of equipment by the preventive maintenance unit and a result of the equipment health evaluation by the health monitoring unit; Execute.

[0010] The plant reliability evaluation program of the present invention includes a procedure in which a computer measures a corrosion potential in the water quality of a lower plenum region of a nuclear reactor by using an electrochemical corrosion potential sensor; A first sampling pipe connected to the drain pipe of the reactor a step of measuring a hydrogen concentration in reactor water of the nuclear reactor by a water quality measuring device; a step of measuring a dose rate of a piping of the nuclear reactor by a dose rate monitor; a step of storing in a storage unit the composition of materials constituting the reactor, deterioration data of the materials, and inspection results; The corrosion potential, the hydrogen concentration, and the dose rate, which are environmental information of a plant in operation, and information on the importance of the equipment constituting the plant. , the material composition, the material degradation data, the inspection results a procedure for constantly monitoring the health of the equipment constituting the plant based on the above, a procedure for instructing preventive maintenance of the equipment based on the results of the health evaluation of the equipment during operation, Corrosion potential While monitoring the In the lower plenum area adjusting the amount of hydrogen injected by a hydrogen injection device into the feedwater of the reactor so that the corrosion potential is reduced to a target value; The measurement results of the first water quality measuring device In the reactor water Water Steps for adjusting the concentration of the element, A procedure for formulating a repair plan for the plant based on preventive maintenance instructions for corrosion of the equipment and results of an evaluation of the soundness of the equipment; This is to carry out the above. Other means will be described in the description of the embodiment of the invention. Effect of the Invention

[0011] According to the present invention, by simultaneously utilizing in-service inspection and operating parameters of a nuclear facility, the reliability of equipment can be improved, including not only conventional equipment but also large structures such as structural materials, welds, etc. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a diagram showing reliability and life cycle management of equipment in the nuclear power plant according to the present embodiment. [Diagram 2] FIG. 1 is a configuration diagram of a reliability evaluation system for a nuclear power plant. [Diagram 3] FIG. 1 is a configuration diagram of a nuclear power plant. [Figure 4] FIG. 2 is a diagram illustrating a hardware configuration of a server. [Diagram 5] FIG. 2 is a hardware configuration diagram of a terminal. [Figure 6] FIG. 1 is a functional block diagram of a reliability evaluation system for a nuclear power plant. [Figure 7] FIG. 1 is a diagram illustrating reliability and life cycle management of weld lines in a nuclear power plant. [Figure 8] FIG. 1 is a diagram illustrating reliability and life cycle management of piping in a nuclear power plant. [Figure 9] 10 is a flowchart showing a periodic inspection process of a comparative example. [Figure 10] FIG. 1 is a diagram showing reliability and life cycle management of equipment in a nuclear power plant of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, a comparative example will be described with reference to Figures 9 and 10, and a preferred embodiment of the present invention will be described with reference to Figures 1 to 8. In the following description, the same components will be denoted by the same reference numerals and the description will be omitted as appropriate.

[0014] Operation of Comparative Example 9 is a flow chart showing a routine inspection process of a comparative example, which is carried out with the nuclear power plant shut down. The inspector starts the inspection during the periodic inspection (step S40). In the comparative example, the structural materials, weld lines, etc. related to the soundness of the reactor are inspected and evaluated separately. The inspector evaluates the inspection results (step S41) and sets the inspection cycle (step S42).

[0015] Next, the inspector replaces the facility / equipment (step S43), and reflects this in a large-scale repair plan (step S44). Finally, the inspector evaluates the plant life (step S45), and ends the process of FIG.

[0016] Figure 10 is a diagram showing the reliability and life cycle management of equipment in a nuclear power plant of a comparative example, and is based on AP-913 of the Nuclear Power Operations Association of the U.S. AP-913 is a diagram showing the process for managing the reliability of equipment and facilities related to the operation of a power generating nuclear reactor and the life cycle of the plant.

[0017] First, the management system classifies the importance (step S50), and monitors performance according to this importance (step S51). Then, the manager continuously improves the reliability of the equipment according to this importance (step S53). The manager performs preventive maintenance of the facility / equipment (step S54). The facility / equipment for which preventive maintenance has been performed becomes the target of the performance monitoring process (step S51).

[0018] Based on the performance monitoring results, the manager takes corrective measures for the facility / equipment (step S52). The results of the corrective measures are then fed back to the performance monitoring process (step S51) and the process of continuously improving the reliability of the equipment (step S53).

[0019] Finally, the administrator performs life cycle management (step S55) based on the continuous equipment reliability improvement process (step S53), corrective measures (step S52), and performance monitoring process (step S51).

[0020] Operation and Configuration of the Present Embodiment In this embodiment, the reliability of the entire power plant is visualized by introducing a soundness assessment of structural materials and large structures into the conventional AP913 approach.

[0021] In preparation for more than 40 years of operation, it will be possible to constantly monitor the reliability of not only conventional equipment but also large structures such as structural materials and weld seams. This will be reflected in optimal inspections, equipment replacement, and large-scale repair work, optimizing costs while ensuring reliability.

[0022] FIG. 1 is a diagram showing reliability and life cycle management of equipment in a nuclear power plant according to this embodiment. The reliability evaluation system S shown in Fig. 2 classifies structures by their importance (step S10). The importance of a structure is determined based on factors that affect the safety system in the reactor, the integrity of the fuel in the reactor, and the release of radioactive materials outside the system, and is determined not only by legal requirements but also by the results of conventional inspections, the fluids that the structure comes into contact with under operating conditions, and the types and concentrations of chemical substances contained in the reactor water in the reactor pressure vessel during operation.

[0023] The types of structures classified in step S10 include reactor pressure vessels, shrouds, shroud supports, jet pumps, grid plates and other reactor internal structures, equipment related to the insertion of control rods, turbine casings, bearings, condensers, generators and hydrogen supply equipment, heat exchangers of the old condensate system, fuel support plates, main piping connecting equipment whose safety importance and power generation importance are higher than the threshold, etc. Nuclear facilities include fuel processing plants, nuclear fuel cycle plants, radioactive waste disposal sites, etc.

[0024] In step S11, the reliability evaluation system S monitors the soundness of the structure. The monitoring of the soundness involves evaluating the current reliability of the structure based on previous inspection results and conventional knowledge such as the operational status of the plant P, maintenance specifications, standards, and papers. The reliability evaluation system S may further monitor the soundness of the structure based on periodic inspection information of the plant P.

[0025] Based on the type of structure classified in step S10, the reliability evaluation system S continuously improves the reliability of the equipment (step S13). Specifically, the reliability evaluation system S performs inspection and mitigation (step S14). In the inspection step, the reliability evaluation system S selects an inspection frequency and inspection method that minimizes costs while ensuring reliability, taking into account the inspection results, maintenance standards, laws, and regular inspection processes. In the mitigation step, the reliability evaluation system S instructs the worker's terminal 6 to perform stress relaxation and / or environmental mitigation (step S14). In response to this, the worker performs stress relaxation and / or environmental mitigation for the structure.

[0026] The reliability evaluation system S takes measures for the operation method based on the monitoring results of the soundness of the structure (step S12). Here, the measures for the operation method refer to improvements in the operation and operation method of the plant P, enhanced sampling, operation changes of mitigation techniques, etc.

[0027] The reliability evaluation system S optimizes the repair plan based on the results of the health monitoring, the results of the countermeasures for the operation method, and the results of the continuous reliability improvement of the structure (step S15). The optimization of the repair plan here is life cycle management, and large-scale construction and inspection are required. Therefore, the reliability evaluation system S optimizes the plan to minimize costs while ensuring the reliability of the structure, taking into account the long-term regular inspection process.

[0028] FIG. 2 is a configuration diagram of a reliability evaluation system S for a nuclear power plant P. The reliability evaluation system S includes a server 5, a usage environment information sensor 58, a corrosion potential sensor 4, and a plurality of terminals 6.

[0029] The server 5 is a computer that embodies the functional parts of the reliability evaluation system S. The terminal 6 is an input / output device for accessing the server 5. The usage environment information sensor 58 is a sensor that detects the usage environment of the equipment that constitutes the plant P. The corrosion potential sensor 4 is a sensor that detects corrosive environment information of the equipment that constitutes the plant P.

[0030] FIG. 3 is a configuration diagram of a nuclear power plant P. The plant P is a boiling water nuclear power plant, and includes a reactor pressure vessel 20, a reactor containment vessel 21, a turbine 22, a recirculation system piping 23, a reactor cleanup system 24, and a plurality of corrosion potential measuring devices. The reactor pressure vessel 20 installed inside the reactor containment vessel 21 has a core 25 loaded with a plurality of fuel assemblies (not shown) disposed therein.

[0031] Each of the two recirculation systems has a recirculation system piping 23 and a recirculation pump 26. A main steam piping 27 connected to the reactor pressure vessel 20 is connected to the turbine 22. A condenser 28 connected to the turbine 22 is connected to the reactor pressure vessel 20 through a condensate piping 29 and then a feedwater piping 30. An off-gas system piping 31 is connected to the condenser 28. The off-gas system piping 31 is connected to the condensate piping 29, and a dose rate monitor 32 is installed near the main steam piping 27.

[0032] The reactor clean-up system 24 has piping connected to the recirculation system piping 23 and a drain piping 33 connected to the bottom of the reactor pressure vessel 20, and has a purification device (not shown) within the system. The reactor clean-up system 24 is connected to the feedwater piping 30.

[0033] Water quality measuring device 34a is connected to drain pipe 33 by sampling pipe 35a, and water quality measuring device 34b is connected to reactor cleanup system 24 by sampling pipe 35b. Water quality measuring device 34c is connected to feedwater pipe 30 by sampling pipe 35c, and water quality measuring device 34d is connected to main steam pipe 27 by sampling pipe 35d.

[0034] The corrosion potential sensor 4 is installed at a relevant location in the boiling water nuclear power plant using the local power range monitor outer cylinder tube 1. The corrosion potential sensor 4 is installed at a corresponding position in the lower plenum 36 in order to measure the water quality in the lower plenum 36 at the bottom of the reactor pressure vessel 20. In this case, in order to measure the corrosion potential near the pressure vessel bottom head 8, the corrosion potential sensor 4 is installed at a height near the pressure vessel bottom head, and a corrosion potential measurement window is opened at that height (not shown).

[0035] In the corrosion potential measurement using the local power range monitor, it is not possible to obtain a direct correspondence with the sampled water quality such as oxygen, hydrogen peroxide, etc. However, in the case of the corrosion potential measurement near the pressure vessel bottom head 8 as described above, the reactor water can be sampled using the sampling pipe 35a and measured by the water quality measuring device 34a.

[0036] By measuring the corrosion potential in this manner, the amount of hydrogen injected into the feedwater from the off-gas system piping 31, which is a hydrogen injection device, is adjusted so that the corrosion potential in the lower plenum 36 falls to a target value. The surplus hydrogen injected into the reactor water in the reactor pressure vessel 20 is exhausted to the off-gas system piping 31 via the main steam piping 27, the turbine 22, and the condenser 28. The surplus hydrogen exhausted to the off-gas system piping 31 is combined with oxygen in a recombiner (not shown) provided in the off-gas system piping 31 and treated.

[0037] The hydrogen concentration of the feedwater is obtained by measuring the feedwater sampled through sampling pipe 35c with water quality measuring device 34c. The dose rate of main steam pipe 27 during hydrogen injection is monitored by dose rate monitor 32.

[0038] In this method, since a plurality of corrosion potential sensors 4 can be arranged on the local power range monitor outer tube 1, by installing them at a plurality of locations in the boiling water nuclear power plant, it is possible to three-dimensionally map the corrosive environment in which stress corrosion cracking (SCC) occurs in the structural members of the boiling water nuclear power plant within the lower plenum 36. As a result, it is possible to provide a maintenance measure for ensuring the long-term safety, soundness, and reliability of the nuclear power plant.

[0039] FIG. 4 is a diagram showing the hardware configuration of the server 5. As shown in FIG. The server 5 is, for example, a computer installed in a data center. The server 5 includes a central processing unit (CPU) 51, a storage unit 57, a read only memory (ROM) 52, a random access memory (RAM) 53, an operation unit 54, a display unit 55, and a communication unit 56.

[0040] The CPU 51 is a central processing unit, and executes a program 571 stored in the storage unit 57. The program 571 is executed by the CPU 51 to perform each process shown in FIG. The CPU 61 embodies each of the functional units shown in Fig. 6 by executing the program 571. Note that each process executed by the CPU 61 will be described later with reference to Figs.

[0041] The storage unit 57 is a large-capacity storage device, and is configured, for example, by a hard disk drive or a flash memory.

[0042] The RAM 53 is a volatile memory and functions as a work area for temporarily storing various programs executable by the CPU 51, input data, output data, parameters, etc. The ROM 52 is a non-volatile memory and stores, for example, a BIOS (Basic I / O System) and the like.

[0043] The operation unit 54 is configured with a keyboard equipped with cursor keys, numeric input keys, various function keys, etc., and a pointing device such as a mouse. The operation unit 54 detects press signals of keys pressed on the keyboard and operation signals from the mouse. The CPU 51 executes various processes based on the operation signals from the operation unit 54.

[0044] The display unit 55 is configured to include a monitor display such as an LCD (Liquid Crystal Display). The display unit 55 displays various screens according to a display signal input from the CPU 51. The display unit 55 and the operation unit 54 may also employ a touch panel display.

[0045] FIG. 5 is a diagram showing the hardware configuration of the terminal 6. As shown in FIG. The terminal 6 is, for example, a tablet terminal owned by each worker. The terminal 6 includes a CPU 61, a storage unit 67, a ROM 62, a RAM 63, a touch panel display 64, and a communication unit 66.

[0046] The CPU 61 is a central processing unit, and executes a program 671 stored in the storage unit 67. The program 671 is, for example, a browser, and is executed by the CPU 61 to realize input / output processing with the server 5.

[0047] The storage unit 67 is a large-capacity storage device, and is configured, for example, by a hard disk drive or a flash memory.

[0048] The RAM 63 is a volatile memory and functions as a work area for temporarily storing various programs executable by the CPU 61, input data, output data, parameters, etc. The ROM 62 is a non-volatile memory and stores, for example, a BIOS.

[0049] The touch panel display 64 is a display such as an LCD with a transparent touch panel superimposed on it. The touch panel display 64 detects a pressing signal generated when the touch panel is pressed. The CPU 61 executes various processes based on the operation signal from the touch panel display 64. The touch panel display 64 displays various screens based on a display signal input from the CPU 61.

[0050] FIG. 6 is a functional block diagram of a reliability evaluation system S for a nuclear power plant. The reliability evaluation system S includes a detection unit 511 , an importance classification unit 512 , a regular inspection information receiving unit 513 , a health monitoring unit 514 , a preventive maintenance unit 515 , and a life cycle management unit 516 . The detection unit 511 detects environmental information of the operating plant P. The environmental information detected by the detection unit 511 includes any of the types and concentrations of chemical substances contained in the reactor water of the reactor pressure vessel in operation, the types of materials, and construction data at the time of construction.

[0051] The health monitoring unit 514 constantly monitors the health of the equipment constituting the plant P based on environmental information of the plant P during operation and importance information of the equipment constituting the plant P. Note that the health monitoring unit 514 may also constantly monitor the health of the equipment constituting the plant P based on periodic inspection information and / or standard information of the plant P, and is not limited thereto.

[0052] The preventive maintenance unit 515 instructs preventive maintenance for each device, based on the result of the health evaluation of the devices constituting the plant P during operation by the health monitoring unit 514. The life cycle management unit 516 develops a repair plan for the plant P based on preventive maintenance instructions for corrosion of the equipment from the preventive maintenance unit 515 and the results of the equipment health evaluation from the health monitoring unit 514.

[0053] The regular inspection information receiving unit 513 receives input of regular inspection information and / or standard information of the plant P. Note that the regular inspection information receiving unit 513 is not an essential component.

[0054] The importance classifying unit 512 classifies the importance of the devices that configure the plant P. Note that the importance classifying unit 512 is not an essential component, and the importance of the devices may be classified manually.

[0055] FIG. 7 is a diagram showing the reliability and life cycle management of weld lines in a nuclear power plant. Types of weld lines include those found on reactor pressure vessels, shrouds, shroud supports, jet pumps, lattice plates and other reactor internal structures, equipment related to the insertion of control rods, turbine casings, bearings, condensers, generators and hydrogen supply equipment, and the joints between structures and piping such as heat exchangers in the old condensate system.

[0056] The reliability evaluation system S classifies the weld lines by their importance (step S20). The importance of the weld line is determined by influencing factors such as the safety system in the reactor, the integrity of the fuel in the reactor, whether it affects the release of radioactive materials outside the system, whether it is determined by law, conventional knowledge, factors that affect long-term integrity evaluation such as the welding method, the type of welding, the metal used in welding, post-processing such as polishing after welding, the fluid that comes into contact, and the type and concentration of chemical substances contained in the reactor water in the reactor pressure vessel during operation.

[0057] The reliability evaluation system S monitors the soundness of the weld line (step S21). Specifically, the monitoring of the soundness of the weld line is to evaluate the current reliability of the weld line based on the results of previous inspections and the operational status of the plant P, maintenance specifications, standards, papers, and other conventional knowledge.

[0058] Based on the type of weld line classified in step S20, the reliability evaluation system S continuously improves the reliability of the equipment (step S23). Specifically, the reliability evaluation system S performs inspection and mitigation (step S24). In the inspection, the reliability evaluation system S selects an inspection frequency and inspection method that minimizes costs while ensuring reliability, taking into account the inspection results, maintenance standards, laws, and regular inspection processes. Then, in the mitigation, the reliability evaluation system S instructs stress relaxation and / or environmental relaxation (step S24). In response to this, workers perform stress relaxation and / or environmental relaxation on the weld line.

[0059] The reliability evaluation system S takes measures for the operation method based on the monitoring result of the soundness of the weld line (step S22). Here, the measures for the operation method refer to improvements in the operation and operation method of the plant P, enhanced sampling, operation changes of mitigation techniques, etc.

[0060] The reliability evaluation system S optimizes the repair plan based on the results of the health monitoring, the results of the countermeasures for the operation method, and the results of the continuous improvement of the reliability of the equipment (step S25). The optimization of the repair plan here is life cycle management, and large-scale construction and inspection are required. Therefore, the reliability evaluation system S optimizes the plan to minimize costs while ensuring the reliability of the facilities and equipment, taking into account the long-term regular inspection process.

[0061] FIG. 8 is a diagram showing the reliability and life cycle management of piping in a nuclear power plant. The type of piping includes the type of fluid that flows through it, its material, whether it is installed on the reactor side, turbine side, or rad equipment. The type of liquid includes whether it contains water, steam, or chemicals.

[0062] The reliability evaluation system S classifies the piping by its importance (step S30). The importance of the piping is determined based on whether it affects the safety system in the reactor, the integrity of the fuel in the reactor, the release of radioactive materials outside the system, whether it is determined by law, company regulations, or standards, and environmental factors such as the concentration of radioactive materials and the type and concentration of chemical substances.

[0063] The reliability evaluation system S monitors the soundness of the piping (step S31). Specifically, the monitoring of the soundness of the piping evaluates the current reliability of the piping based on the results of previous inspections, the operating state of the plant, maintenance codes, standards, papers, and other conventional knowledge.

[0064] Based on the type of weld seam classified in step S30, the reliability evaluation system S continuously improves the reliability of the equipment (step S33). Specifically, the reliability evaluation system S performs inspection and mitigation (step S34). In the inspection step, the reliability evaluation system S selects an inspection frequency and an inspection method that minimize costs while ensuring reliability, taking into account the inspection results, maintenance standards, laws, and regular inspection processes. Then, in the mitigation step, the reliability evaluation system S performs stress relaxation and / or environmental mitigation.

[0065] The reliability evaluation system S takes measures for the operation method based on the monitoring result of the soundness of the weld line (step S32). Here, the measures for the operation method refer to improvements in the operation and operation method of the plant P, enhanced sampling, operation changes of mitigation techniques, etc.

[0066] The reliability evaluation system S optimizes the repair plan based on the results of the health monitoring, the results of the countermeasures for the operation method, and the results of the continuous improvement of the reliability of the equipment (step S35). The optimization of the repair plan here is life cycle management, and large-scale construction and inspection are required. Therefore, the reliability evaluation system S optimizes the plan to minimize costs while ensuring the reliability of the equipment, taking into account the long-term regular inspection process.

[0067] By incorporating the corrosion environment, material composition, material deterioration data, and inspection results that were obtained during in-service inspections into the equipment reliability instead of the equipment reliability stipulated by the Institute of Nuclear Power Operations (INPO) in the United States, it becomes possible to constantly monitor the deterioration status of structures, equipment, and systems, making it easier to constantly monitor the health of Plant P and evaluate the plant life cycle.

[0068] <<Variation>> The present invention is not limited to the above-described embodiment, and includes various modified examples. For example, the above-described embodiment has been described in detail to clearly explain the present invention, and is not necessarily limited to those having all of the configurations described. It is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. In addition, it is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

[0069] The above configurations, functions, processing units, processing means, etc. may be realized in part or in whole by hardware such as an integrated circuit. The above configurations, functions, etc. may be realized by software by a processor interpreting and executing a program that realizes each function. Information such as the program, table, file, etc. that realizes each function can be stored in a recording device such as a memory, a hard disk, or an SSD (Solid State Drive), or a recording medium such as a flash memory card or a DVD (Digital Versatile Disk).

[0070] In each embodiment, the control lines and information lines are those that are considered necessary for the explanation, and not all control lines and information lines in the product are necessarily shown. In reality, it may be considered that almost all components are connected to each other. [Explanation of symbols]

[0071] S Reliability Evaluation System 1 Local Power Range Monitor Outer Tube 20. Reactor Pressure Vessel 21 Reactor Containment Vessel 22 Turbine 23 Recirculation system piping 24 Reactor Cleanup System 25 Core 26 Recirculation Pump 27 Main steam pipe 28 Condenser 29 Condensate piping 30 Water supply pipe 31 Off-gas system piping 32 Dose rate monitor 33 Drain piping 34a~34d Water quality measuring device 35a~35c Sampling piping 35d Sampling piping 4. Corrosion potential sensor 5 Server 51 CPU 511 Detection unit 512 Importance classification section 513 Periodic Inspection Information Reception Department 514 Health Monitoring Department 515 Preventive Maintenance Department 516 Life Cycle Management Department 52 ROM 53 RAM 54 Control section 55 Display section 56 Communications Department 57 Memory section 58 Operating environment information sensor 6 Terminal 61 CPU 62 ROM 63 RAM 64 Touch Panel Display 66 Communications Department 67 Memory section

Claims

1. a corrosion potential sensor for measuring the corrosion potential of the water chemistry in the lower plenum region of the reactor; a first water quality measuring device connected to a drain pipe of the reactor by a sampling pipe and configured to measure a hydrogen concentration in the reactor water; a dose rate monitor for measuring a dose rate in the reactor piping; A memory unit that stores the composition of materials constituting the reactor, deterioration data of the materials, and inspection results; a health monitoring unit that constantly monitors the health of the equipment constituting the plant based on the environmental information of the plant during operation, which is the corrosion potential, the hydrogen concentration, and the dose rate, as well as importance information of the equipment constituting the plant, the material composition, the deterioration data of the material, and the inspection results; instructing preventive maintenance of the equipment based on a result of the health evaluation of the equipment during operation by the health monitoring unit; a preventive maintenance unit that adjusts an amount of hydrogen injected by a hydrogen injection device into the feed water of the reactor while monitoring the corrosion potential, and adjusts a hydrogen concentration in the reactor water of the reactor, which is a measurement result by the first water quality measurement device, so that the corrosion potential of the lower plenum region is reduced to a target value; a life cycle management unit that develops a repair plan for the plant based on preventive maintenance instructions for corrosion of equipment by the preventive maintenance unit and on the results of the equipment health evaluation by the health monitoring unit; A plant reliability evaluation system comprising:

2. A second water quality measuring device connected to the purification system of the reactor by a sampling pipe and measuring a hydrogen concentration; a third water quality measuring device connected to the reactor water supply pipe by a sampling pipe and measuring a hydrogen concentration; a fourth water quality measurement device connected to the main steam pipe of the reactor by a sampling pipe and configured to measure a hydrogen concentration; 2. The plant reliability evaluation system according to claim 1, further comprising:

3. The plant is a power plant including a nuclear reactor pressure vessel.

2. The plant reliability evaluation system according to claim 1 .

4. The equipment is related to control rod insertion and reactor internals.

4. The plant reliability evaluation system according to claim 3.

5. The equipment is any one of a reactor pressure vessel, a shroud, a shroud support, a jet pump, a lattice plate, a fuel support plate, and a main piping connecting equipment whose safety importance and power generation importance are higher than a threshold value; 4. The plant reliability evaluation system according to claim 3.

6. The equipment includes any one of a structure, a welded line, and a pipe.

4. The plant reliability evaluation system according to claim 3.

7. a regular inspection information receiving unit that receives input of regular inspection information and / or standard information of the plant; Further comprising: the health monitoring unit constantly monitors the health of the equipment constituting the plant based on the environmental information during operation, importance information of the equipment constituting the plant, the material composition, deterioration data of the material, inspection results, regular inspection information of the plant, and / or standard information; 2. The plant reliability evaluation system according to claim 1 .

8. an importance classification unit that classifies the importance of equipment constituting the plant; 2. The plant reliability evaluation system according to claim 1, further comprising:

9. a corrosion potential sensor measuring a corrosion potential in a water chemistry in a lower plenum region of the nuclear reactor; a first water quality measuring device connected to a drain pipe of the reactor by a sampling pipe and measuring a hydrogen concentration in the reactor water; a dose rate monitor measuring a dose rate in a piping of the nuclear reactor; A step in which a memory unit stores a material composition constituting the reactor, deterioration data of the material, and an inspection result; a health monitoring unit constantly monitors the health of the equipment constituting the plant based on environmental information of the plant during operation, which is the corrosion potential, the hydrogen concentration, and the dose rate, as well as importance information of the equipment constituting the plant, the material composition, deterioration data of materials, and inspection results; A preventive maintenance unit instructs preventive maintenance of the equipment based on a result of the health evaluation of the equipment during operation by the health monitoring unit; the preventive maintenance unit monitors the corrosion potential and adjusts the amount of hydrogen injected by the hydrogen injection device into the feed water of the reactor so that the corrosion potential of the lower plenum area is reduced to a target value, thereby adjusting the hydrogen concentration in the reactor water of the reactor, which is a measurement result by the first water quality measurement device; A life cycle management unit develops a repair plan for the plant based on a preventive maintenance instruction for corrosion of equipment by the preventive maintenance unit and a result of the equipment health evaluation by the health monitoring unit; A plant reliability evaluation method comprising the steps of:

10. The computer A procedure for measuring the corrosion potential in the water quality of the lower plenum region of a nuclear reactor by means of an electrochemical corrosion potential sensor; measuring a hydrogen concentration in reactor water of the reactor by a first water quality measuring device connected to a drain pipe of the reactor by a sampling pipe; measuring a dose rate in said reactor piping with a dose rate monitor; a step of storing in a storage unit the composition of materials constituting the reactor, deterioration data of the materials, and inspection results; a procedure for constantly monitoring the soundness of the equipment constituting the plant based on the environmental information of the plant during operation, which is the corrosion potential, the hydrogen concentration, and the dose rate, as well as the importance information of the equipment constituting the plant, the material composition, the deterioration data of the materials, and the inspection results; a procedure for instructing preventive maintenance of the equipment based on a result of the health evaluation of the equipment during operation; a step of adjusting the amount of hydrogen injected by a hydrogen injection device into the feed water of the reactor while monitoring the corrosion potential, so that the corrosion potential of the lower plenum region is reduced to a target value, and adjusting the hydrogen concentration in the reactor water, which is a measurement result by the first water quality measurement device; A procedure for formulating a repair plan for the plant based on preventive maintenance instructions for corrosion of the equipment and results of an evaluation of the soundness of the equipment; A plant reliability assessment program to carry out.

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