Hollow turbine blade 3D wall-thickness analysisbased on its ict measurement data

The wall thickness of aero-engine hollow turbine blade is a very critical parameter for ensuring its strength, which needs to be carefully inspected in the production stage. A template based 3D normal direction wall-thickness auto analysis method using its cone beam CT (computed tomography) images and CAD (computer aided design) model was introduced. Sub pixel level edge detection algorithm was adopted to extract accurate inner and outer blade surface point cloud data from its CT images. In order to enhance the calculation efficiency, evenly grid data structure was used to hold the point cloud. Then, through the intersecting calculation between the wall thickness analysis template exported from the blade CAD model and the point cloud data, the 3D wall thickness deviation distribution of the predefined region would be generated automatically. A set of simulation data was used to verify the precision of the discussed 3D wall thickness calculation method.