The basic raw material for the manufacture of sand is the casting sand and the binder of sand type. The most commonly used casting sand is silica sand. The high temperature performance of silica sand can not meet the requirements of the use of zircon sand, chromium iron ore, corundum sand and other special sand. In order to make the sand type and core has a certain strength, in the handling, molding and pouring liquid metal will not be deformed or damaged, generally in casting to add a type of sand binder, loose sand particles bonded to become the type of sand. The most widely used sand binder is clay, and can also be used in a variety of drying oil or semi-drying oil, water-soluble silicate or phosphate and a variety of synthetic resins for the sand binder.
Sand mold Casting used in the sand type of the binder used in accordance with the type of sand and the way to build strength are divided into clay wet sand type, clay dry sand type and chemical hardening sand type 3 kinds.