Patent ID: 8225844

Claim:
A method for processing molding sand comprising the following steps: a) dividing the molding sand to be processed into at least two molding sand portions; then, b) adding a first molding sand portion to be processed to a mixer; then, c) moving a mixing tool provided in the mixer; then, d) measuring the force required to move the mixing tool; then, e) determining the actual compressibility of the molding sand portion in the mixer from the measured force; then, f) determining the difference between the actual compressibility and a reference compressibility; then, g) determining the quantity of water to be added to the molding sand portion in the mixer from the difference; then, h) adding the quantity of water determined in g) to the molding sand portion; then, i) moving the mixing tool provided in the mixer for a predetermined period of time; then, j) measuring the force required to move the mixing tool; then, k) determining the actual compressibility of the processed first molding sand portion from the measured force; then, l) determining the difference between the actual compressibility and the reference compressibility; then, m) determining a corrective quantity of water or a corrective quantity of new sand or a corrective quantity of clay from the difference between the actual compressibility and the reference compressibility; then, n) repeating steps b) to m) with a second molding sand portion to be processed, wherein before or together with step h) the corrective quantity of water or the corrective quantity of new sand or the corrective quantity of clay is added to the further molding sand portion.