Aiming at the problems of low efficiency, poor uniformity, and poor consistency of the existing burr removal process for the intersecting-hole parts top shell in the servo mechanism, a suggestion of using the abrasive flow deburring process was proposed. Through the analysis of the internal structure of the workpiece and the planning of the deburring processing path, the runner simulation model of each processing path was established, and the flow field characteristics of the corresponding path of each inlet runner group were compared, analyzed and optimized for better process path. Deburring verification experiments were carried out on the top shell workpiece. The results show that the uneven distribution of the streamline inside the flow channel and the large difference in the streamline pressure can be effectively improved by increasing the drainage section structure at the exit of the large hole and extending the length of the flow channel. Finally, the problem of inconsistent burr removal effect during processing can be solved and the sharp edges at the entrance and exit can also be effectively protected. After the experiment, the internal burrs of the runner are removed, and the edges of the internal small holes are rounded, which improves the surface quality and performance of the workpiece.