Shell mold stacking casting process of fastener and wall-through screw nut

The invention discloses a process comprising three steps, namely precoated sand molding, stacking and pouring, wherein the precoated sand molding is as follows: connecting a mold for a fastener and a wall-through screw nut with a core shooting machine together, placing sand in a hopper of the core shooting machine, using the core shooting machine to shoot the sand into the mold cavity of a mold, heating to 240 DEG C and getting one shell mold at an interval of 50 seconds; the stacking is as follows: taking out the shell molds and stacking a plurality of the shell molds together; and the pouring is as follows: injecting molten iron into the mold cavity from the top of the shell molds which are stacked together in a centralized manner so as to cast the fastener and the wall-through screw nut. The casting process has the advantages of high production efficiency, uniform thickness of a product, aesthetic appearance of the product, high utilization rate of the molten iron and low production cost.