Analysis And Research Of Expert System For Hydraulic System Fault Diagnosis In Wood-based Panel Hotpress

With the development of economy and standard of living, Wood-based panel Industry's development is rapid more and more. The key machine of Wood-based panel manufacturing is hotpress, which hydraulic system is more and more complex and it make fault diagnosis of hydraulic system is more and more difficult. Because hydraulic system's working medium work in obturation, press instrument and flowmeter cann't measure easily the state of working medium, so hydraulic system's default is difficult for precision diagnosis. At present, the administration and maintenance of hydraulic system are very weak in wood-based panel hotpress, neglecting the accumulation of the original fault record ,the historical fault record and the theoretical summary of the diagnostic experience. Most of the experience is not turned into systematic written materials which make the diagnosis and maintenance have little systematic science in them. It is necessary that building wood-based panel hotpress hydraulic system fault diagnosis system with perfect reasoning and hugeness repository, So it is imperative for us how to excavate,arrange and take the advantage of the experience of the experts to make efficient diagnosis . This thesis summarizes the fault histories of common wood-based panel hotpress hydraulic system, building knowledge database, studying and designing fault diagnosis system according to the characteristic of wood-based panel hotpress hydraulic system faulting. Fault diagnosis system is made with friendly man-machine conversation interface that took Windows mac os as developing flat,Visual BASIC program language and ACCESS database language as developing tools. This system adopt belief measure theory to collecting expert's knowledge,blend reasoning control tactic and deep priority search tactic to express full diagnosis structure arrangement, cause and effect relationship fairly, which improve knowledge express ability and knowledge's strictness. Database have preferable maintenance, which can delete,append and search convenient for expert system's maintenance and expansion. This system has huge database contain familiar 29 fault phenomenon, overlay hydraulic pump,hydraulic valve,hydraulic urn,pipeline and hydraulic accessory 160 piece of fault information etc. This system is accurate and credible through simulation experiment on QD hotpress. For the first time, apply the expert system in the hotpress hydraulic system fault diagnosis of wood-based panel industrial equipment. This diagnosis system enhances the efficiency and accuracy for hydraulic fault diagnosis in wood-based panel hotpress and provides the base for the further studying on it, and it is significant to improve the efficiency of wood-based panel industry.