Failure Analysis And Performance Evaluation Of Local Stability Of Real - Length Telescopic Boom

With the rapid development of social economy,mobile cranes are widely used in various fields, such as truck crane and all terrain crane, etc. At the same time, requirements are also increasing to cranes and crane safety issues are more and more important. The solid web type telescopic jib, as the key part of the mobile cranes, is a determinant for the lift and safety. Telescopic jib which is large thin-walled structures is mostly instability. Currently, there is no security and life assessment methods to the telescopic jib existed local buckling defects in service.To solve the above problems, the stability of the in-service solid telescopic jib is studied. Focus of the paper is local stability of telescopic jib that has been generated local buckling in-service. Firstly, parameter modeling can be established with APDL language of ANSYS software and the jib model of mobile cranes can be changed by parameter adjustment. Secondly, overall instability of jib is analyzed and the critical buckling load is extracted with two methods which are eigenvalue buckling analysis and geometric nonlinear analysis. The method is proposed to acquire jib buckling critical load. Third, the telescopic jib existed local buckling defects in service is studied with the sub-model technology. It can be used to analyze safety margin of jib defect, determine local buckling critical point, research on the defect’s impact to local stability and provide a basis for life prediction and remanufacturing entry point for jib in service. A new idea is proposed for the jib that presented buckling failure in-service. Finally, the secondary development software is established by method that ANSYS is retrieved by C#.Studies have shown that the use of geometric nonlinear buckling analysis is more reasonable to forecast jib buckling critical load; When there are different buckling failures at the jib cylinder support structure, the impact on the local stability is different; It can greatly enhance the analysis efficiency and enhance software usability that using parametric modeling approach and software retrieval form.