METHOD FOR ADJUSTING COMPACTABILITY OF MOLDING SAND

摘要

PURPOSE:To adjust the compactability of molding sand with high accuracy by measuring the compactability index of recovered sand after primary water addition and kneading for specified time and executing the corrected secondary water addtion to adjust the index to a desired value from the coefft. of correcting moisture at said index. CONSTITUTION:The recovered sand is subjected to the primary water addition and kneading for specified time and after the stable state is attained, the compactability coefft. CB1 of the sand is measured in the case of adding water to the recovered sand and using said sand. The coefft. CB after the kneading for the specified time and the coefft. DELTAW/DELTACB for correcting the moisture are in a linear expression relation. The coefft. DELTAW/DELTACB1 for correcting moisture with respect to the above-mentioned CB1 is obtd. from the straight line graph and is multiplied by the difference from the desired coefft. CBP to obtain the required correction quantity for the secondary water spraying, by which the secondary water spraying is corrected. The compactability of the reconditioned sand is corrected. The compactability of the reconditioned sand is adjusted with the much higher accuracy and efficiency than in the conventional manual or other intuitional adjustments.