Mechanical Anslysis And Structural Optimization Of Auto- Fixture For Bolt Joint

Bolted joint is the most key piece of grid components, its quality directly affects the quality and safety of grid. LAN Zhou University of Technology undertake State Planning Commission key research project, named " arbitrary distribution center of screw hole on the sphere CNC machining equipment development", and developed a new type of automatic indexing of nodes ball clamping device, who can process joint node automatically and effectively .There are some defects found in daily usage, its performance needs to be further improved.This research based on vibration and optimal design theory, adopting finite element method, using finite element software ANSYS to proceed a static and dynamic analysis, and then proceed a structural optimization for the device. Researches completed in this paper are as following:First of all, proceeding a static analysis of the device and the key components to identify the main factors affecting the deformation and stress distribution for further improvement.Secondly, proceeding a dynamic analysis for the key components of the device and overall to identify the main factors affecting the stability for further improvement. A new method, using V-shaped spring element to simulate normal and tangential stiffness of the contact surface, is put forward innovative in the dynamic analysis.Thirdly, through the static and dynamic analysis we find out that a large deformation at the dovetail rail ramp, large stress located at the joint of equivalent nut and screw and a significant swing at the connection part of screw and dovetail slide. In order to reduce the deformation we use the rectangle guide rail instead of dovetail rail. To lower the maximum stress, we make a sudden increase in end units of each. We use the cross-shaped cross section in stead of rectangular cross section in the middle of the connection and reduce the weight of the structure and increase dynamic stiffness and improve the stress distribution.Fourthly, sensitivity analysis for clamping device is proposed based on parameter optimization of the finite element method .proceeding a sensitive analysis to determine the parameter used in further optimization analysis.In comparison with original model, the optimized model has been greatly improved in the static and dynamic performance.Last , posed in this article, parametric sensitivity analysis based optimization approach is not just for the clamping device research, study and improvement but for the other kinds of complex mechanical systems as well, so the research methods and conclusions of this paper has a broad engineering significance.