Security Evaluation System Of Metal Structure Of Portal Slewing Crane Based On Expert Repository

With the constant deepening of opening to the world,the ports develop rapidly along with the international trade’s development.The mechanical equipments are also constantly moving in the direction of becoming larger,continuous and automated.At the same time,the possibility of mechanical equipment’s failure is increasing, the safety issue has become the major issue to the port enterprises.As the typical kind, there is great practical meaning for the safety research on portal slewing crane and there is also a certain degree of representation to all the cranes in ports.Taking the cylindrical type of the portal slewing crane as an example,the method of multiple indicators is used to assess the security of the portal slewing crane metal structure,and the safety assessment process is described in detail.The theoretical research on expert repository is divided into two aspects: knowledge processing and repository’s establishing and maintaining. There are three different ways to obtain the security evaluation knowledge. The security evaluation is analysed with two factors,which are the design factor and the fault factor.An expert repository is set up by analysing the two factors above,which includes the aspects below.The single component’s and the whole machine’s security assessment indicators are determined by referencing to the indicators-constructing principles of the security evaluation.Multi-component and multi-factor safety assessment system of multi-layer crane metal structure is also established. Combined with the existing theory,the thesis proposes the method to determine the state value of various indicators and ascertains the limit value of the assessment indicators.The positive and negative nature of the single-component indicators of the security evaluation are analysed and ascertained,too.The weight in every assessment layer and every single indicator is established by using the method of dividing the weights on average.Combined with the existing theoretical knowledge of zero dimension,the non-dimensional treatment of different evaluation indicators is established.The arithmetic average model is used to synthesize the evaluation value of the indicators of the normal component and the geometric average model is used to synthesize the evaluation value of the main components of the whole machinery.Finally, the inference engine of the evaluation system is established.The computer programming language Visual C#2.0is used to develop the security evluation system of the portal slewing crane metal structure.Combined with the test data in the port,the thesis elaborates the security evaluation process.The feasibility of the research methods and the practicability of the evaluation system are also verified.