Dalian marine parts are used for marine machinery, which requires higher quality of castings, especially compactness. In the process design of casting, the layout of riser, exhaust needle and chill is very important for the process design of external mold, especially for the upper mold; When designing the sand core process, the layout and connection of the exhaust channel between each sand core, the exhaust channel between the sand core and the mold cavity, and the channel between the sand core and the upper profile exhaust needle are the difficulties in designing the sand core process. The design of exhaust system and riser is related to the success of the casting process. Through comprehensive consideration, including gating system, riser, exhaust needle and chill. 4 is sand core assembly, including pouring system, exhaust system and sand core positioning. Since the development of SLA Photoforming technology in the mid-1980s to the late 1990s, dozens of different RP technologies have emerged. In addition to the above-mentioned ones, typical ones include 3DP, etc. However, SLA, LOM, SLS and FDM are still the mainstream of RP technology.