JPH04344967A - Supporting device for equipment maintenance management optimization - Google Patents

Abstract

PURPOSE:To support the optimization for the equipment maintenance management by evaluating the fault mode and fault influence degree of equipments and parts for object of maintenance in a power generation plant and deciding the maintenance priority. CONSTITUTION:It is composed of a central processing unit(CPU) equipped with primary and secondary data bases, and having function of a keyboard, a CRT, printer information processing and control. A program is stored in a ROM, and operation/maintenance data, installation data, and basic data are stored in the primary data base. On the other hand, reliability evaluation data, fault analysis data, and maintenance management/evaluation data are stored in the secondary data base and constructed by inputting the estimation result using the primary data. In this case, the check item for information selection shall be the evaluation of the specification of the maintenance system, reliability evaluation analysis, maintenance priority, fault analysis, time up to fault, and fault characteristic, and the maintenance priority is decided by fault influence degree and maintenance system by evaluating the fault mode and fault influence degree in the power generation plant.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support device for optimizing equipment maintenance management in a power generation plant.

0002

[Prior Art] Conventionally, reliability-oriented maintenance (RC) for aircraft has been used as a decision-making method for systematic inspection and inspection optimization of equipment consisting of a huge number of devices and parts.
M), and how to apply it to nuclear power plants can be found in Thermal and Nuclear Power Generation Vol. 41 No. 5, pages 11 to 19.

[0003] Furthermore, Japanese Patent Application Laid-open No. 63-208716 relates to the maintenance management of large-scale plant equipment, and describes how to predict and manage the lifespan of plant equipment and parts based on failure and maintenance records, and to develop appropriate maintenance methods. A technique is disclosed that reduces the labor and time required for maintenance management of plant equipment. On the other hand, Japanese Patent Application Laid-Open No. 2-69619 also relates to maintenance management of equipment in large plants, and in particular, equipment maintenance based on a statistical life evaluation method based on maintenance performance data and a maintenance status evaluation method that converts expert knowledge into logic. A technique for diagnosing a situation and supporting decision-making for equipment maintenance work based on the diagnosis has been disclosed.

0004

[Problem to be solved by the invention] RCM of the above-mentioned prior art
According to the decision logic tree (LTA), it is possible to select whether maintenance work is unnecessary or the type of maintenance work (CD-PM or TD-PM), but consideration must be given to optimizing the maintenance method for each degree of failure impact. No consideration is given to evaluation points based on specific maintenance data (actual results) such as evaluation of time to failure, analysis of failure cases, and evaluation of countermeasure effects, and from the perspective of optimizing inspections, FMEA, The problem was that it was biased toward analytical evaluations such as LTA, and the RCM decision logic tree had many ambiguous points and lacked specificity.

[0005] Furthermore, the technology disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 63-208716 does not take into consideration the functions of the equipment configuration of the parts or the usage environment conditions, and even the same type of equipment and parts cannot be used. Different plants have different inspection cycles and replacement periods, and there are many cases where the planned cycle and the actual maintenance cycle are different. Furthermore, the technology disclosed in Japanese Unexamined Patent Publication No. 2-69619 performs reliability evaluation analysis on equipment and parts to be maintained, determines the degree of failure impact, and determines maintenance priority based on the degree of failure impact. No consideration is given to optimizing the method.

An object of the present invention is to comprehensively and systematically evaluate each item related to failure using information related to maintenance, and to present the comprehensive evaluation to support optimization of equipment maintenance management.

[0007]

[Means for Solving the Problem] The above object is to provide an input section for specifying equipment to be maintained and its maintenance method, equipment information of the equipment, equipment operation/maintenance information, and basic information of equipment maintenance in advance. reliability evaluation means for evaluating a failure mode and failure impact degree based on an input database, information input from the input means and information from the database; and maintenance determining a maintenance priority based on the failure impact degree and the maintenance method. a priority determination means, a time-to-failure evaluation means for evaluating the validity of an inspection cycle for equipment whose maintenance priority is determined to be high; and a time-to-failure evaluation means for important parts, for extracting corresponding failures from the database. A failure analysis method, a failure characteristic evaluation method that determines the optimal maintenance method based on the failure pattern when extending the equipment inspection cycle, and a preset maintenance optimization logic are used to determine the optimal equipment maintenance management based on the combination of the above examination results. This is achieved by comprising an information processing section having a comprehensive evaluation means that outputs comprehensive evaluation information that supports the evaluation, and an output section that displays the comprehensive evaluation information output by the comprehensive evaluation means.

[0008]

[Operation] According to the above configuration, the reliability evaluation means for the equipment and parts to be maintained in the power generation plant is based on the information about the equipment and parts to be maintained and their maintenance methods inputted from the input means and the information from the database. Evaluate the failure mode and failure impact level, use the failure impact level and the specified maintenance method to determine the maintenance priority using the maintenance priority determining means, and if maintenance is performed according to this maintenance priority, the Since maintenance is performed in sequence, there is no wasted work and it is possible to support optimization of equipment maintenance management.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the apparatus of this embodiment. This device has primary and secondary databases, and is composed of a keyboard for inputting commands and information, a CRT and printer for outputting information, and a central processing unit (CPU) for processing and controlling these information. The program is stored in ROM. The database (primary) stores operation/maintenance data, equipment data, and basic data in advance. On the other hand, the database (secondary) is reliability evaluation data,
Failure analysis data and maintenance management/evaluation data are stored, and these data are constructed by inputting the results of evaluation using primary data according to the examination procedure. This device selects and outputs the requested screen to the CRT using keyboard operations, and outputs the evaluation results after setting the conditions, and is primarily used for discussions in an interactive manner.

FIG. 2 shows a flowchart of the process of combining the evaluations obtained by examining each consideration item to obtain a comprehensive evaluation. As a means of efficiently organizing a wide range of information and making it possible to select appropriate information, we have carefully selected the following six items to consider that are necessary for decision-making. The items to be considered are (1) identification of maintenance method, (2) reliability evaluation analysis, (3) maintenance priority,
(4) Failure analysis, (5) Evaluation of time to failure, (6)
This is an evaluation of failure characteristics. The depth of the study is such that each item is examined down to the level of each component and failure mode of the system's component equipment. In addition, as a method of inspection/inspection optimization, the optimal maintenance work is selected and
This method employs a method of determining recommendations by using preset maintenance optimization logic. In other words, this logic incorporates knowledge and experience for optimization.

[0012] To systematically accumulate information, a database is constructed for each type of information. In addition, CRT provides the necessary information in a timely manner and provides a functional output display.
In addition to making it possible to select and narrow down the output items for optimization by selecting factors and items, the standard output sheet is determined after consideration, and related outputs that you want to see are displayed simultaneously in a window on the same CRT screen. I did it like that. For example, in the output display of a failure cause diagram or FMEA sheet, if the user wants to know the material of the displayed component, the device specifications are output in a window.

[0013] Specifications such as names and types of systems, equipment, and parts are registered in the equipment database. The operating hours, inspection dates, and inspection details are entered for each piece of equipment into the operation/maintenance database. The basic database stores data such as maintenance optimization logic, equipment design data, classification definitions and keyword explanations used for maintenance classification, etc.

[0014] A fault tree diagram is created for the target device/component, and a failure mode and effect analysis (FMEA) is performed to identify failure modes and evaluate the degree of failure influence. Furthermore, the importance of components/failure modes (probability that a base event (failure mode of equipment or components) contributes to the failure of the top event (system or equipment)) is evaluated using failure tree analysis (FTA) or failure mode effects and Determined by criticality analysis (FMECA). The results of these reliability evaluation analyzes are stored in the reliability evaluation database and maintenance management/evaluation database. For critical parts with high importance (for example, the top 10 in importance), the corresponding failures are extracted from the operation/maintenance database and failure analysis is performed.

[0015] Maintenance priority is determined from a combination of maintenance method and failure impact degree for parts/failure modes, and the validity of the current maintenance method is evaluated. Preventive maintenance must be performed if the failure of such equipment impairs the safety of the plant or leads to problems with power generation. Of these, for maintenance priority 1 and 3 (improvement required due to TD-PM), the time until failure or time until parts replacement obtained from the operation/maintenance database and the parts life stored in the equipment design database. Evaluate the validity of the inspection cycle by comparing it with the time (design value). If the time to failure or time to parts replacement based on actual operating results is shorter than the design value, perform a failure analysis, and if the actual inspection cycle is longer than the design value and there is a need to extend the inspection cycle, evaluate the failure characteristics. conduct.

[0016]Failure analysis clarifies the target system for the result (failure situation), the cause system, and the countermeasure system. In the process of analysis, these include the use of reliability evaluation analysis results, verification of suitability of materials, structure, strength, capacity, etc. based on design evaluation items and maintainability design contents obtained from equipment design databases, and comparison between equipment specifications and failures. This is done by examining correlations and confirming the effectiveness of the measures taken. Evaluate the adequacy of current maintenance by clarifying the cause of failure and the effectiveness of countermeasures.

In evaluating the failure characteristics, one pattern is identified from among the six patterns of failure rate curves, and the maintenance method is optimized for each pattern. For failure characteristics other than those with increasing failure rate, time-scheduled maintenance may actually increase the number of failures, which is not preferable. In this case, condition monitoring maintenance, enhanced screening before product installation, or modification after finding the cause of the failure (
(based on failure analysis) is required.

The above results are stored in a maintenance management/evaluation database and summarized as a comprehensive evaluation.
Output on top. This information contributes to decision-making for inspection and inspection optimization.

FIGS. 3 to 8 show detailed flowcharts of the program of this embodiment. When the program starts, there is an option to register and calibrate the database (D/B), which allows you to register and calibrate the D/B. When the program inputs the maintenance method for each plant name, system name, and equipment name, and also the failure impact degree of reliability evaluation analysis results for each part name and failure mode, the maintenance priority and optimum according to the input conditions are shown in Figure 14. output action 1. When there is an instruction to proceed to the next step in optimization action 1, or when critical parts are extracted by FTA, proceed to failure analysis. In failure analysis, the source of failure and the effectiveness of countermeasures are input from the results of searching and sorting the contents of failure records for plant name, system name, equipment name, component name, and failure mode. Based on these conditions, the program outputs recommendations regarding whether the inspection cycle can be extended. When evaluating the time until failure, input the time until failure, time until parts replacement, and parts service life, and based on these conditions, the program outputs recommendations regarding whether the inspection cycle can be extended. When evaluating failure characteristics, the failure rate curve pattern and failure characteristics are input, and based on these conditions, the program outputs recommendations for extending the inspection cycle. When the input and evaluation are completed, a comprehensive evaluation of the plant name, system name, equipment name, component name, and failure mode is output to the CRT as the evaluation result. Furthermore, the contents of the maintenance management/evaluation database can be output by inputting necessary data items from the keyboard. The database (primary) includes equipment database, operation/maintenance database, and basic database. In the equipment database, specifications such as names, models, etc. of systems, equipment, and parts are registered. The basic database stores data such as maintenance optimization logic, equipment design data, classification definitions and keyword explanations used for maintenance classification, etc. One output example of each database is shown in FIGS. 9 to 11.

FIG. 9 shows an example of equipment specifications for a pump, which is an important equipment in a plant, and the type, capacity, parts materials, etc. are registered.

FIG. 10 is an output example of a pump inspection and maintenance history, in which inspection date, inspection category, parts replacement history, etc. are input.

FIG. 11 is an output example of the content explanation of the maintenance optimization logic.

FIG. 12 shows a flowchart of reliability evaluation analysis. A failure cause diagram (F
(fault tree diagram) and identify the cause of the failure.

FIG. 13 shows an example of a failure cause diagram for a pump. Next, a failure mode and effect analysis (FMEA) is performed to determine the failure influence rank of the component/failure mode.

FIG. 14 shows pump failure mode influence analysis (F
An example of FMEA) is shown below. Here, rank A of failure impact degree is
indicates that the failure of the equipment would impede the safety of the plant;
Rank B indicates that the failure of the device will hinder power generation, and rank C indicates that there is no effect. Furthermore, the importance of the component/failure mode (this combination is called the basic event) (the probability that the basic event contributes to the failure of the top event) is calculated using failure tree analysis (FTA) or failure mode influence and criticality analysis ( FM
ECA). For critical parts with high importance, for example, the top 10 in importance, the corresponding failures are extracted from the operation/maintenance database and failure analysis is performed. Furthermore, the results of these reliability evaluation analyzes are stored in a reliability evaluation database.

Failure analysis clarifies the result (failure situation), target system, cause system, and countermeasure system. In the process of analysis, these are: 1) Utilization of reliability evaluation analysis results, 2) Verification of suitability of materials, structure, strength, capacity, etc. based on design evaluation items and maintainability design contents provided from the equipment design database, and 3) This is done by examining the correlation between equipment specifications and failures, and confirming the effectiveness of the measures taken.

FIG. 15 shows items to be considered in failure analysis. Here, the abnormality level is classified as shown in FIG. 16, and analysis is normally performed on whether the abnormality level is catastrophic, serious, or minor. However, when considering latent failures (discernible physical conditions that indicate impending functional failure), symptoms of abnormal levels are also subject to analysis.

FIG. 17 shows an example of failure analysis results. This example is an analysis of a seawater pump, and the results (failure status) are evaluations of the causes and effectiveness of countermeasures against large pump vibrations, abnormal bearing wear, etc. In both cases, the cause of the failure was due to poor design and was not due to maintenance. As a result of failure analysis, if the cause of the failure is determined to be due to design factors such as material, structure, strength, capacity, etc., and countermeasures are evaluated to be highly effective, the evaluation results of the time to failure will also be taken into account. The current inspection cycle will be extended. Through failure analysis, we clarify the causes of failures and the effectiveness of countermeasures, and evaluate the adequacy of current maintenance. The failure analysis results are stored in the failure analysis database in an organized form as shown in the example shown in FIG.

[0029] Maintenance priority is determined from a combination of maintenance methods and failure effects for parts and failure modes, and the validity of the current maintenance method is evaluated. This technique is a unique feature of the present invention that has not been seen before. The maintenance method for the target equipment and parts was determined by investigating the inspection frequency and inspection contents obtained from the operation and maintenance database, and then determining the maintenance classification (JIS Z8115) shown in Figure 18 given from the basic database.
Specify according to the following.

FIG. 19 shows the evaluation results of maintenance priority and optimization action 1. This maintenance priority and optimization action 1 determines the combination of failure influence degree and maintenance method determined by the reliability evaluation analysis based on the maintenance optimization logic registered in the basic database. Cases in which the failure of the equipment impedes plant safety or interferes with power generation and the maintenance method is corrective maintenance are out of the question, and preventive maintenance must be performed. In addition, for maintenance priority items 1 and 3, consideration item (5) is applied to evaluate the validity of the inspection period.
Evaluate the time until failure. The evaluation results of maintenance methods and maintenance priorities are stored in the maintenance management/evaluation database.

[0031] Evaluate the validity of the current inspection cycle by comparing the time until failure or time until parts replacement obtained from the operation/maintenance database and the component service life (design value) given from the equipment design database. do.

FIG. 20 shows a flowchart for evaluating the time until failure and optimizing the maintenance method. Search for cases of failures (targeting abnormal levels C, M, and D) or normal replacement of parts (replacement during periodic inspections, etc.) by target part and failure mode from the operation/maintenance database and sort by date. Sort and list the time until failure (=TB) or time until parts replacement (=TC). On the other hand, component service life (design value=TA) is similarly listed from the equipment design database and compared. When TB or TC does not reach TA, the cause of the failure and the effectiveness of countermeasures are checked from the failure analysis database, and if it is determined that there is no problem, the inspection cycle is extended. If TB or TC is the same as or longer than TA, the current maintenance is continued. moreover,
If there is a need to improve maintenance methods, such as extending the inspection cycle, evaluate the failure characteristics in consideration item (6). In addition, in some cases, we aim to improve maintenance methods by adopting improved or new products.

FIG. 21 shows the time until failure and the evaluation results of optimization action 3. Although it is not possible to decide whether or not the inspection cycle can be extended based on a single logic, this device is considered effective because it allows the lifespan of parts to be determined from the aspects of design values, operating results, and failure analysis. . The evaluation results of time until failure are stored in the maintenance management/evaluation database.

[0034] Failure characteristics refer to patterns of changes in failure rate curves over time, and it is necessary to perform maintenance appropriate for each failure characteristic.

FIG. 22 shows a flowchart for evaluating failure characteristics and optimizing maintenance methods. In evaluating failure characteristics, the failure rate curve pattern of the target component/failure mode is investigated based on the operation/maintenance database, and identified according to the failure rate curve pattern classification shown in FIG. 23 given from the basic database. Optimization action 4 is determined from a combination of failure characteristics, maintenance method, and failure analysis results.

FIG. 24 shows failure characteristics and optimization action 4.
The evaluation results are shown below. In the relationship between failure characteristics and inspection intervals, the optimal maintenance period is at the annual limit (the year when it enters the wear region)
This is last-minute maintenance. For failure characteristics other than those with increasing failure rate, time-scheduled maintenance may actually increase the number of failures, which is not preferable. In this case, condition monitoring maintenance, enhanced screening before product integration, or modification after finding the cause of failure (based on failure analysis) is required. The evaluation results of these failure characteristics are stored in a maintenance management/evaluation database. The evaluation results stored in the maintenance management/evaluation database can be
Output to RT.

FIG. 25 shows an output example of the evaluation results. This output example is sorted by component and failure mode, and is organized by inspection details, cause,
This is a list of failure cases, etc. In addition, as a comprehensive evaluation, the results of each consideration item and the evaluation results based on maintenance optimization logic are output on one sheet for each component and failure mode.

FIG. 26 shows an example of output of comprehensive evaluation. In this example, the maintenance method is appropriate for the current TD-PM, and it has been evaluated as a critical component.

Since this embodiment is constructed as described above, it produces the effects described below.

[0040]B. Using the device of this example, all the equipment and parts targeted for the power generation plant are examined by the reliability evaluation analysis (FTA, FMEA) of item (2) to identify failure causes and evaluate the impact on the plant, and the subsequent items to be considered ( By evaluating the maintenance priority in 3), it is possible to easily identify "things that cause unplanned plant shutdowns because no maintenance has been done at all." Furthermore, consideration item (1)
The correlation between inspection content and failure can be evaluated in failure analysis and evaluation of time to failure in consideration item (5), and the relationship between equipment/parts, inspection content, and inspection cycle can be clearly seen in the subsequent comprehensive evaluation. From this, it is possible to judge the validity of the current inspection cycle. This optimizes inspections and inspections.

B. In order to review whether excessive inspections are being carried out during periodic inspections without any correlation to the service life of parts or the rate of deterioration, and whether unnecessary inspections are causing a decline in equipment utilization rate or exposure to radiation, 1) In evaluating the time to failure in item (5), consider the time to failure and time to parts replacement from operation and maintenance data, and the parts service life (from equipment design data).
The validity of parts replacement time can be determined by comparing and considering the design value), so appropriate maintenance can be carried out based on the service life of the parts.

2) Grasp the pattern of the failure rate curve for the failure mode of the device/component in the evaluation of failure characteristics in consideration item (6), and examine the abnormality level and cause of failure in the failure analysis in consideration item (4). - By listing the results of examining the effectiveness of countermeasures over time, the relationship between maintenance and the rate of deterioration of parts can be clarified, allowing for appropriate maintenance that takes into account the rate of deterioration of parts.

3) By specifying the maintenance method in consideration item (1) and evaluating the failure characteristics in consideration item (6), a decision can be made as to whether or not inspection is unnecessary. For example, if the failure characteristic is DFR and the maintenance method is TD-PM, the inspection is determined to be unnecessary. In this case, inspection may actually increase the number of failures.
It can be said that it is not desirable. Through the above steps, inspections and inspections are optimized.

C. Although the inspection cycle cannot be completely optimized using simple logic, since the device according to this embodiment can clarify the characteristics of parts and their failures, it is possible to determine how to maintain them (whether the inspection cycle can be extended, etc.). It is possible to provide accurate information on whether to increase the frequency of inspections, etc.).

d. By operating the equipment according to this implementation, the economic efficiency and reliability of the plant will be significantly improved.

[0046]

[Effects of the Invention] According to the present invention, the reliability of equipment and parts to be maintained in a power generation plant can be improved by using information on equipment and parts to be maintained and their maintenance methods input from the input means and information from the database. If the evaluation means evaluates the failure mode and failure impact degree, the maintenance priority determination means determines the maintenance priority based on the failure impact degree and the specified maintenance method, and if maintenance is performed according to this maintenance priority,
Since maintenance is performed in the order of importance for the power plant, there is no wasted work and it is possible to support optimization of equipment maintenance management.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart of a process for obtaining an overall evaluation of an embodiment of the present invention.

FIG. 3 is a detailed flowchart of the flowchart shown in FIG. 3;

FIG. 4 is a detailed flowchart of the flowchart shown in FIG. 3;

FIG. 5 is a detailed flowchart of the flowchart shown in FIG. 3;

FIG. 6 is a detailed flowchart of the flowchart shown in FIG. 3;

FIG. 7 is a detailed flowchart of the flowchart shown in FIG. 3;

FIG. 8 is a detailed flowchart of the flowchart shown in FIG. 3;

FIG. 9 is an example of outputting equipment data (pump equipment specifications) according to the embodiment of the present invention.

FIG. 10 is an example of output of operation/maintenance data (pump inspection/maintenance history) according to the embodiment of the present invention.

FIG. 11 is an output example of basic data (classification and content explanation of maintenance optimization logic) according to the embodiment of the present invention.

FIG. 12 is a reliability evaluation analysis flowchart of the embodiment of the present invention.

FIG. 13 is an output example of a failure cause diagram (pump) according to the embodiment of the present invention.

FIG. 14 is an example of output of failure mode effect analysis (pump) according to the embodiment of the present invention.

FIG. 15 shows items to be considered in failure analysis of the embodiment of the present invention.

FIG. 16 is a classification of abnormality levels according to an embodiment of the present invention.

FIG. 17 is an example of output of failure analysis results (pump) according to the embodiment of the present invention.

FIG. 18 is an explanatory diagram of general maintenance classification.

FIG. 19 is an example of output of evaluation results of maintenance priority and optimization action 1 according to the embodiment of the present invention.

FIG. 20 is a flowchart for evaluating the time until failure and optimizing the maintenance method according to the embodiment of the present invention.

FIG. 21 is an example of the output of evaluation results of time-to-failure optimization action 3 according to an embodiment of the present invention.

FIG. 22 is a flowchart for evaluating failure characteristics and optimizing maintenance methods according to the embodiment of the present invention.

FIG. 23 is a classification diagram of general failure rate curve patterns.

FIG. 24 is an example of output of evaluation results of failure characteristics and optimization action 4 according to the embodiment of the present invention.

FIG. 25 is an output example of evaluation results for each consideration item in the embodiment of the present invention.

FIG. 26 is an example of output of comprehensive evaluation of the embodiment of the present invention.

[Explanation of symbols]

Claims (1)

[Claims] 1. An input unit for specifying equipment to be maintained and its maintenance method; a database into which equipment information of the equipment, operation/maintenance information of the equipment, and basic information of equipment maintenance are input in advance; and the input means. reliability evaluation means for evaluating a failure mode and failure impact degree using information input from the database and information from the database; a maintenance priority determining means for determining a maintenance priority based on the failure impact degree and the maintenance method; For equipment that has been determined to have a high priority, there is a time-to-failure evaluation means that evaluates the validity of the inspection cycle; for important parts, there is a failure analysis means that extracts corresponding failures from the database; and equipment inspection. When extending the cycle, we use a failure characteristic evaluation method that determines the optimal maintenance method based on the failure pattern, and comprehensive evaluation information that supports optimization of equipment maintenance management from a combination of the above examination results using preset maintenance optimization logic. 1. A support device for equipment maintenance management optimization, comprising: an information processing section having a comprehensive evaluation means for outputting; and an output section for displaying comprehensive evaluation information output by the comprehensive evaluation means.