Molding sand reclamation method and reclamation equipment

A molding sand reclamation method comprising:

• measuring a water content and a magnetized matter content of molding sand discharged from green sand casting equipment;
• comparing the measured water content with a first control value, and if the water content exceeds the first control value, drying the molding sand until the water content becomes equal to or less than the first control value;
• comparing the measured magnetized matter content with a second control value, and if the magnetized matter content exceeds the second control value, magnetically separating the molding sand until the magnetized matter content becomes equal to or less than the second control value;
• thereafter, reclaiming the molding sand by dry mechanical reclamation until a loss-on-ignition becomes equal to or less than a third control value;
• and
• classifying the molding sand until a total clay content becomes equal to or less than a fourth control value.

A molding sand reclamation method comprising:

• recovering molding sand that has been discharged from green sand casting equipment, separately as overflow sand, sand adhering to the product, main mold/core-mixed sand and sand lumps/sand;
• drying the overflow sand until the water content is equal to or less than a first control value, removing foreign matter from the overflow sand, and storing the overflow sand;
• removing foreign matter from the sand adhering to the product, magnetically separating the sand adhering to the product until the magnetized matter content is equal to or less than a second control value, and storing the sand adhering to the product;
• crushing the main mold/core-mixed sand, removing foreign matter from the main mold/core-mixed sand, and storing the main mold/core-mixed sand;
• crushing the sand lumps, removing foreign matter from the sand, and storing the sand;
• extracting and blending the stored overflow sand, the stored sand adhering to the product, the stored main mold/core-mixed sand and the stored sand so that a ratio therebetween is always kept constant;
• reclaiming the blended sand by dry mechanical reclamation until a loss-on-ignition becomes equal to or less than a third control value;
• and
• classifying the blended sand until a total clay content becomes equal to or less than a fourth control value.

Molding sand reclamation equipment comprising:

• drying equipment that dries molding sand discharged from green sand casting equipment until a water content is equal to or less than a first control value;
• magnetic separation equipment that magnetically separates the molding sand until a magnetized matter content is equal to or less than a second control value;
• dry mechanical reclamation equipment that reclaims the molding sand until a loss-on-ignition is equal to or less than a third control value;
• classification equipment that classifies the molding sand until a total clay content is equal to or less than a fourth control value;
• first switching equipment that selects whether or not to pass the molding sand through the drying equipment;
• and
• second switching equipment that selects whether or not to pass the molding sand through the magnetic separation equipment.

Molding sand reclamation equipment comprising:

• overflow sand recovery equipment that recovers overflow sand discharged during a sand processing step;
• drying equipment that dries the overflow sand until a water content is equal to or less than a first control value;
• overflow sand foreign-matter removal equipment that removes foreign matter from the overflow sand;
• an overflow sand storage tank that stores the overflow sand;
• product-adhered sand recovery equipment that recovers sand adhering to the product;
• product-adhered sand foreign-matter removal equipment that removes foreign matter from the sand adhering to the product;
• magnetic separation equipment that magnetically separates the sand adhering to the product until a magnetized matter content is equal to or less than a second control value;
• a product-adhered sand storage tank that stores sand adhering to the product;
• main mold/core-mixed sand recovery equipment that recovers main mold/core-mixed sand;
• crushing equipment that crushes the main mold/core-mixed sand;
• main mold/core-mixed sand foreign-matter removal equipment that removes foreign matter from the main mold/core-mixed sand;
• a main mold/core-mixed sand storage tank that stores the main mold/core-mixed sand;
• sand lumps/sand recovery equipment that recovers sand lumps/sand discharged during a core sand extraction step;
• crushing equipment that crushes the sand;
• sand foreign-matter removal equipment that removes foreign matter from the sand;
• a sand storage tank that stores the sand;
• sand cutting/blending equipment that cuts out and blends sand from the overflow sand storage tank, the product-adhered sand storage tank, the main mold/core-mixed storage tank and the sand storage tank so that the ratio between the sand extracted from the respective storage tanks is always constant;
• dry mechanical reclamation equipment that reclaims the blended sand until a loss-on-ignition becomes equal to or less than a third control value;
• and
• classification equipment that classifies the blended sand until a total clay content becomes equal to or less than a fourth control value.