Study on the inner surface finishing of irregular spatial elbow pipe by the centerline reconstruction

Due to the compact space structure of aerospace engine, the structure of the inner spatial elbow pipe of the engine exhibits irregular geometric characteristics, which makes the inner surface of the curved pipe difficult to polish, especially the bending place’s surface quality cannot be ensured. It is centerline reconstruction that can be a good solution to this problem, which measures the outer surface contour line and generates the spatial point cloud of the elbow pipe and thus, the irregular geometric centerline of the spatial elbow pipe is rebuilt. Furthermore, the polishing path of the spatial elbow pipe is calculated and optimized. At the same time, using of magnetic abrasive finishing (MAF) has well in flexible machining characteristics, the outer space of the elbow pipe is loaded with rotating magnetic field, so as to get form a “magnetic abrasive brush” inside the tube, achieve the purpose of bending the inner surface finishing. Under the same processing time, compared with the pure manual measuring magnetic grain processing, the reconstruction of the center line of the magnetic processing can make the space bend surface roughness lowered to 0.11 μm, which improves the processing quality of the tube surface and the processing efficiency.