This product is mainly used in cast iron, cast steel wet type, surface dry type, dry type and high pressure molding as molding sand binder, compared with other similar products in China, the product has high montmorillonite content, excellent wet compressive strength and hot wet tensile strength, high expansion and good thermal stability, using the product can improve the reuse of molding sand, reduce the amount of bentonite addedand reduce the moisture of the sand system, increasethe strength and toughness of the molding sand, improve the air permeability, improve the casting quality , solve the problems of casting sand clamping, scarring, lumping, porosity, sand punching and sand mold collapse, as well as reduce the rejection rate, so as to reduce the production cost and storage and transportation costs of foundry enterprises.