Research On Reliability Analysis And Fault Diagnosis Expert System Of Belt Conveyor

As the most widely used continuous conveying machine with the high efficiency and long conveying distance, belt conveyor is an indispensable part of mining machinery. With more complicated working conditions and the longer delivery distance, the higher quality of belt conveyor is needed. In the design process of the belt conveyor, the reliability is a key factor which must be considered. A systematic reliability analysis of the belt conveyor and the targeted improvement and maintenance are conducted so as to control its probability of failure and improve the reliability. Then a fault diagnosis system suitable for belt conveyor based on reliability analysis is designed and it can be used to find the fault reason rapidly and accurately when anything goes wrong with the belt conveyor. The outage rate can be reduced and the reliability of belt conveyor is improved.For the above requirements, a set of reliability analysis system applied to the belt conveyor is proposed in this thesis and used to analysis the reliability of belt conveyor. A fault diagnosis expert system for belt conveyor is designed based on reliability analysis. The main research contents and conclusions are presented as follows:(1) The preliminary reliability analysis model of the belt conveyor is established by analyzing the structure and functional principle of belt conveyor. Then the agreed level and analysis process of reliability analysis are developed according to the relevant reliability analysis standards. Furthermore, the failure data is combined to establish the failure mode database based on the FMEA.(2) Comparing the reliability analysis methods FMECA and FTA, an FTF reliability analysis method is proposed by taking advantage of two methods’ advantages. The FMECA analysis of the belt conveyor is conducted at first, and then FTA analysis is carried on with the top event which caused by high severe degree basic events. Then the cause of the malfunction and the importance degree of basic events were obtained. And the weak links of belt conveyor are also gotten by sorting the results. The analysis results can be reference of reliability design and maintenance of belt conveyor.(3) The basic principle and design method of fault diagnosis expert system based on FTF analysis is studied. The diagnostic rules and logical relation of events of FTF are connected, and weight the results of FMECA and FTA quantitative analysis used to endow the priority level of every rule. Combining the frameworks and rules to represent the diagnostic knowledge, then the knowledge base of belt conveyor based on FTF is established. The reasoning mechanism based on diagnostic rules and priority is designed to find the fault reason by analyzing layer by layer. The performance of expert system is tested by analyzing the fault reason of drum fault as example, and the result shows us that the performance is well.(4) Using the graphical programming language develops for fault diagnosis system of belt conveyor based on Lab VIEW, the software contains the artificial diagnosis method based on reliability analysis and intelligent diagnosis method based on fault diagnosis expert system. Then the function and operation method of every module of the softwareare introduced in detail.At the end of this thesis, the summarizations of the research and expectation of the related technology development are presented.