Research On Analysing And Controlling Clamping Deformation Of Precision Thin-wall Workpiece

Among the precision parts in aeronautical and astronautical engineering, many parts have thin-wall, complex structure, and high tolerance requirements. Because of the poor rigidity, they are easy to deform when the cutting forces and clamping forces are employed. It is difficult to ensure the machining accuracy using the traditional machining techniques. The purpose of this thesis is to study the deformation problems of precision thin-walled components in the process of clamping and machining. The main work is as follows.Firstly, the principles of fixture-design scheme for precision thin-walled parts were put forward. The influence degree on the deformation of thin-walled parts was theoretically studied with several different fixtures.Secondly, the clamping deformation of the thin-walled parts was studied. Clamping deformations are divided into main deformation and minor deformation. FEM (Finite Element Method) was used to analyze the clamping deformation. Key technologies in FEM was studied and testified.Thirdly, two methods of controlling the clamping deformation were put forward. One is to optimize the positions of locators and clampers in the fixture scheme with a sub-problem iterative optimization method. The other is to clamping the work-pieces with variational clamping forces. Two methods were exemplified.Finally, a prototype system was developed, which can create APDL program based on varied relative parameters, call some commands of the ANSYS software and simulate the deformation result。...