METHOD FOR SEPARATING GREEN SAND MOLD AND AS-CAST MATERIAL AND DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To surely separate an as-cast material from a green sand mold and to surely disintegrate the green sand mold. SOLUTION: The flaskless green sand mold already poured with molten metal is air-tightly surrounded. The inner part of a structural body air-tightly surrounding the green sand mold is rapidly evacuated and reduced to the pressure of not higher than -200 mmHg within 0.5 sec to finally reach the pressure of -360 mmHg in the structural body. In this way, the b.p. of moisture is lowered in the whole green sand mold containing the moisture in a moisture condensed layer formed at the surrounding of the as-cast material in the green sand mold, and this moisture is boiled and the green sand mold is disintegrated and separated from the as-cast material. Thereafter, the as-cast material is taken out after releasing the air-tightly surrounding state.