Research On Theory And Methods Of Maintenance Decision Making For Equipment In Power Plant

With the larger and complicated trend of equipments in power plant, it requires high maintenance. The traditional planned maintenance can bring about"too early or too late"maintenance, which cause a great of loss. It is an effective means to adopt the right maintenance for different equipments. In order to enhance the reliability and security of equipment, reduce maintenance costs, and improve the competitiveness of enterprise, the theory and methods of condition-based maintenance decision making for equipment in power plant are studied in this dissertation.The advantages and disadvantages of planned maintenance are analyzed, and the theory and methods for maintenance decision making based on RCM are put forward in this dissertation. The RCM model for analyzing is conducted, in which fault mode, effect and criticality are analyzed. Based on the qualitative analysis, a quantitative analysis method for the essentiality of fault mode is proposed, which evaluation factors include fault criticality, probability and detectability, and this method is helpful for enterprise to select the right maintenance for different equipments.According to the probability and essentiality of equipments, a strategy of on-line and off-line maintenance is brought forward in this dissertation. Condition monitor and fault diagnosis technology for equipment management are introduced, and the system structure and functions are discussed in detail. The operating information of equipment is put forward, which can be used to implement condition-based maintenance.After the introduction of condition-based maintenance, we put forward its working flow. A method for equipment condition monitoring cycle is proposed by using the reliable data of equipment. According to the vague of equipment state, an evaluation model for equipment is constructed by using fuzzy theory on the basis of the deteriorative degree, which can meet the requirements of the implementation for CBM.The main business processes for equipment management are analyzed in detail, and the function models for the equipment management system based on condition monitoring and fault diagnosis are proposed by means of IDEF. Through the analysis of system information, the data model is constructed. Based on the proposed function and data models, the system is developed by combining computer, network, database and PRAC technology, which can act as a power tool to successfully guarantee the CBM in power plants.