As all known, lost foam casting technology is widely recognized by the casting industry because of its unique advantages comparing with traditional process. Nevertheless, there are still some defacts in lost foam casting process. Sand adhering defect is one of the common casting defects.

Sand adhering defect in lost foam casting appears in different parts in different situations:

    1. Under the condition of no negative pressure, sand ashering defect usually appears at the bottom or side, and on the hot parts or molding sand non-compact zone.

    2. Under the condition of negative pressure, it is possible to occur in every part, especially in the csting corner and overheated place.

The following factors is generally regarded as the reason for sand adhering defect in lost foam casting:

    a. Paint coaling peeling or cracking. That makes liquid metal seep into sand molding, and causes mechanical sand penetration.

    b. The effect of negative pressure degree on the flow ability of molten metal. The greater the negative pressure degree, the better the fluidity of the metal liquid, the easier to form the sticky sand.

As the increasingly competitive foundry industry, requirements in the loss foam castings are increasingly stringent, which gives the domestic EPC enterprises a alarm that, only make maximum efforts to improve the casting quality, and prevent casting defects, such as sand ahering defect, can we develop in the fierce competition and obtain progress.

CHAENG - Great Wall Steel Casting

Email: casting@chaeng.co