3D machining allowance analysis method for the large thin-walled aerospace component

The structural distortion problem of large thin-walled aerospace components has roused much concern on more agile, digitized and cost-efficient precision manufacturing techniques, in particular, designing suitable machining plans according to the real shape of workpieces. To improve the machining accuracy of large thin-walled aerospace components, a methodology of three-dimensional machining allowance modeling and analysis is proposed in this paper. Firstly, the fundamental principles of 3D models matching and alignment between the casting blank and the design part are presented. And by datum transformation from virtual design references to real-world references on casting blanks which are accessible more easily, measuring, positioning and machining the casting blank will be more convenient to realize. Furthermore, the technical character of a large thin-walled aerospace component is considered and a technical framework for 3D machining allowance analysis is given. Finally, the proposed methodology is validated by an experimental study using a typical large thin-walled aerospace component of a hypersonic vehicle. Improvements in accuracy and efficiency performance are realized in comparison with traditional methods.