Foundry engineers have long known that certain AFS standard green sand properties tests provide limited information. This limitation is especially apparent when modern molding technology is employed to enhance green sand casting dimensional control. Furthermore, since sand conditioning involving moisture and/or clay directly affects mold quality more sensitive sand testing is needed. Too much clay in the system is expensive, and reduced bond usage can diminish green strength essential for mold handling. Similarly, high moisture levels equate to gas-related defects and insufficient moisture can cause friable molds. Most AFS standard green sand test are unable to detect the differences between gravity filled green sand and that which has been aeration filled. This paper addresses weather a modified cone jolt green sand test can discriminate between gravity filled green sand and that which has been aeration filled. For mis study gravity and aeration filled green sand specimens were tested using modified cone jolt tester at various target compactability levels. With adjustments to the cone/jolt test parameters subtle differences between gravity and aeration green sand are discerned.
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