With the progress of science and technology and the vigorous development of casting industry, different casting methods have different mold preparation contents. Taking sand mold casting, which is widely used, as an example, mold preparation includes molding material preparation, molding and core making. Various raw materials used for molding and core making in sand casting, such as casting raw sand, molding sand binder and other auxiliary materials, as well as molding sand, core sand and coating prepared from them, are collectively referred to as molding materials. The task of molding material preparation is to select appropriate raw sand, binder and auxiliary materials according to the requirements of castings and the properties of metals, Then they are mixed into molding sand and core sand with certain properties in a certain proportion. Commonly used sand mixing equipment include roller type sand mixer, countercurrent sand mixer and continuous sand mixer. The latter is specially designed for mixing chemical self hardening sand, with continuous mixing and fast sand mixing speed.
Molding and core making are carried out on the basis of determining the molding method and preparing the molding materials according to the requirements of the casting process. The precision of casting and the economic effect of the whole production process mainly depend on this process. In many modern foundry workshops, modeling and core making have been mechanized or automated. Common sand molding and core making equipment include high, medium and low pressure molding machines, air impact molding machines, boxless injection molding machines, cold core box core making machines, hot core box core making machines, coated sand core making machines, etc.
After the casting is taken out from the pouring cooling mold, there are gates, risers, metal burrs and drapes. The casting cast by sand mold also adheres to sand, so it needs to go through the cleaning process. The equipment for this kind of work includes polishing machine, shot blasting machine, pouring and riser cutting machine, etc. Sand falling cleaning of sand castings is a process with poor labor conditions. Therefore, when selecting the molding method, we should try our best to create convenient conditions for sand falling cleaning. Due to special requirements, some castings need post-treatment, such as heat treatment, shaping, antirust treatment, rough machining, etc.