Study On Reliability And Sensitivity Of Metal Structure Of Overhead Travelling Crane Based On Response Surface Method

The safety and reliability of crane girder affects the overall reliability and stability of the hanging weight, and even related to the life safety of the operation personnel, bridge crane in industrial production in modern society plays an important role. It is widely used in various industries, the working environment is very bad especially under full load conditions vulnerable to failure. In addition, such as vibration and impact of accidental factors will affect the crane safety. The work of crane safety reliability assessment, due to the presence of random and unknown factors, resulting in the metal structure of the corresponding random, although using the finite element software can calculate crane under the specific working environment of strength and stiffness, but under complex conditions, it is difficult to quantitatively quantitative crane metal structure on the safety probability value. Therefore, it is of great economic significance to study the reliability and sensitivity of the crane under the condition of considering the randomness of the parameters of the main girder of the crane girder. In accordance with the requirements of the "crane design code", this paper has made three criteria to determine whether the crane is invalid.Because of the crane metal structure complex and parameters of multi variable, function to random variables expressed directly, the direct application of the traditional theory and method on the reliability and sensitivity analysis difficult, using the ANSYS finite element software to the of reliability, sensitivity analysis can avoid solving the implicit function. Model to repeat the process in the analysis, in order to correct and improve efficiency of the model using the command flow parametric modeling, using the visual studio development of powerful function, the APDL language package design the bridge machine reliability analysis of special software system, through the man-machine interaction input data, generate command flow and mobilize the ANSYS analysis and save the analysis result to perform a function in the analysis process confirmed the convenience and high efficiency of the of the system.This paper established a model according to the crane crane metal structure and mechanical characteristics of the actual project, the small failure probability analysis, Monte Carlo method requires many samples, so considering the random variables under the condition of strength, using PDS module in the ANSYS response surface method of crane metal structure static stiffness, the dynamic stiffness reliability and sensitivity are discussed, the reliability can be quantified, obtained by sensitivity analysis of random parameters on the degree and the effect of structure optimization design, can provide reference for the design of metal structure and personnel; to study the changes of the height of girder crane reliability changes.