Collected sand processing method

A method for processing collected sand that is inflected from a main mold of green saint after casting is conducted, including the steps of

• separating each main mold of green sand into a part that has been unaffected by heat of molten metal and a part that has been affected by the heat of the molten metal,
• separately collecting the part that has been unaffected by heat of molten metal and the part that has been affected by the heat of the molten metal,
• adding a binder to the part that has been affected by the beat of the molten metal and adjusting the moisture content in the part,
• mixing at a predetermined ratio the part to which a binder is added and in which the moisture content is adjusted with the part that has been unaffected by the heat of the molten metal, and
• adjusting the moisture content in the mixed material to use it as molding sand, wherein the step for separating the main mold of green sand into a part that has been unaffected by heat of molten metal and a part that has been affected by the heat of the molten metal is achieved by making the pressure negative in an airtight member in which the green sand mold is put just after casting.

A method for processing collected sand that is collected from a main mold of green sand after casting is conducted, including the steps of

• separating each main mold of green sand into a part that has been unaffected by heat of molten metal and a part that has been affected by the heat of the molten metal,
• separately collecting the part that has been unaffected by heat of molten metal and the part that has been affected by the heat of the molten metal,
• mixing at a predetermined ratio the two kinds of collected sand, and
• adding a binder to the mixed sand and adjusting the moisture content in the mixed sand to use it as molding sand.

A method for processing green sand for a main mold that is obtained by separating and collecting a main mold of green sand after casting is conducted, including the steps of

• separating each main mold of green sand into a part that has been unaffected by heat of molten metal and a part that has been affected by the heat of the molten metal,
• separately staring in respective storing means the part that has been unaffected by heat of molten metal and the part that has been affected by the heat of the molten metal,
• processing and collecting the send that is separated and stored in the respective storing means by transferring the sands through the same path at different times, and collecting them in respective storing means,
• mixing at a predetermined ratio the two kinds of collected sand, and
• adjusting the moisture content in the mixed sand to use it as molding sand.

An apparatus for processing collected sand that is separated and collected from a main mold of green sand after casting comprising

• means for separating each main mold of green sand into a part that has been unaffected by heat of molten metal and a part that has been affected by the heat of the molten metal and storing the parts,
• means for separately collecting the part that has been unaffected by heat of molten metal and the part that has been affected by the heat of the molten metal, which parts are separated and stored,
• means for separately storing the part that has been unaffected by the heat of the molten metal and the part that has been affected by that heat, which parts are separately collected,
• clay- and moisture-content-adjusting means for adding a binder to the part that has been affected by the heat and adjusting the moisture content in the part,
• blending means for blending the part that has been unaffected by the heat of the molten metal and the part that has been affected by that heat at a predetermined ratio, and
• mixing means for adjusting the moisture content in the parts and mixing the parts.