Castings - Green Sand for Casting

Summary of uses

Casting is the metal processing method of pouring a molten metal into a mold and castings can be obtained by this method. Many castings are used as parts of automobiles, construction machines, agricultural machines, and machine tools.
A mold used for casting is called a casting mold, a material for a casting mold made by using silica sand as the aggregate and bentonite and water as the caking additives and kneading the mixture is called green sand (or casting sand), and making a casting mold from green sand by compression molding is called mold making. A casting mold obtained by this method is called a green sand mold, and the method of casting using a green sand mold is called green sand casting.
While many processing methods have been developed, green sand casting is used widely around the world because of its low running cost, high productivity per unit time, and other characteristics, and it is believed that about 70% of iron castings, which are used mainly as automobile parts, are made by this casting method. Against such a background, caking additives for green sand for casting are the major application of bentonite in the world.
When bentonite combines with water, it shows a plastic property. Green sand before it is formed into a casting mold also has this property. This is because the properties of the clay are transferred to silica sand coated with the clay.

Bentonite mixtures

The requirements to be met by green sand depend on the casting line. In order to meet various requirements, we provide mixtures of different types of bentonite with different properties (such as highly heat-resistant bentonite and burnable bentonite).

Various types of bentonite

Total engineering

At KUNIMINE, we not only provide bentonite products, but also help customers solve various problems with green sand through our total engineering based on proprietary technologies and know-how accumulated over a long period of time.

Product lineup

Bentonite products

Product name Type Feature
KUNIGEL VAS Na Low water content, Good heat resistance
KUNIBOND TY Na Ease of sand filling, Good heat resistance
NEO-KUNIBOND Artificial Na type Fast-acting property, Ease of mold destruction

Other additives for green sand for casting
 KUNISTACH K (Corn / α-starch)  Coal dust, etc.

Bentonite mixtures



[Feel free to contact us for information.]
We may be able to provide bentonite products already combined with starch or other additives for green sand.