What's is the shell mold casting?

Shell casting was invented by Johannes Cronin in Germany in the 1940s, also known as the Cronin process, which has been widely used; Compared with ordinary sand casting, shell casting has the characteristics of less equipment investment, small footprint, convenient production, high production efficiency, less sand for casting, less dust on the production site, low noise, and thus less pollution to the environment, high surface finish of the production of castings, high dimensional accuracy, and good material properties

The casting method of forming a thin shell cast with a mixture of silica sand or zirconium sand and resin with a high strength thermosetting material and pouring to obtain the casting is called shell casting. The principle is as follows: the preheated (about 280 ~ 320 ° C) metal mold plate is connected to the flip bucket equipped with resin sand, and the flip bucket is turned so that the resin sand falls on the template. When the resin is hot, it melts, and binds the sand to form a thin shell, and then the tipping bucket is reset to make the unfused resin sand fall, and the template with the shell type can be heated to harden the thin shell. Generally divided into two shells, the first layer is the surface layer, can make the casting smooth; The second layer is the strengthening layer, which enhances the strength of the shell. After each crust is heated to harden