SAND QUALITY IN MODERN MOLDING LINES

19730867
Journal: AFS Transactions 1973, p. 129-134, Preprint No. 73-22, $3.00
Author: H.G. Levelink and E. Frank

The authors devised unique tests to measure directly the stripping ability of sand; its flowability; tendency to form scabs; tendency to "water explosion" defects (principally metal penetration); tendency toward mold wall movement; and resistance to erosion. These are illustrated in this paper. It shows clearly how difficulties grow with regard to stripping properties, scabbing tendency and explosion tendency. Raising the clay content has a favorable influence only on stripping properties, scabbing tendency, erosion tendency and mold stability. The explosion tendency is increased, however, and the flowability drops somewhat. In many respect, a higher moisture content has adverse effects, and actually has a favorable influence only on stripping properties and erosion resistance.