Roughing and finishing the mounting surface of the oil pan, quickly remove the irregular machining margin of the forging surface and achieve a more scientific and reasonable surface roughness standard; finishing the pin hole of the oil pan, standardized and efficient reamer, the edge through grinding and polishing processing, can produce a stronger surface roughness and use time! The feed speed can reach 200-500m/min, with stronger machining accuracy and dimensional stability to produce stronger processing safety performance!