The cone jolt toughness test is a dynamic test rather than a static one (such as for compression or shear measurement). A molding sand specimen is subjected to repetitive stressing with relatively light loads, and the number of jolts before failure are counted. It provides a comparative measure of the bulk toughness of a compacted sand specimen, and is sensitive to changes in mulling practice. Responsive to the rate of crack propagation, it is an excellent tool for detecting contaminants that can produce a "brittle" sand.
The weight of a 60° -included-angle steel cone is placed on a specially-prepared 2 in. (50.8 mm) diameter specimen. The support platform is jolted repeatedly until the specimen splits. The cone jolt toughness value is the number of jolts (shown on the counter) required to split the specimen.
Durably constructed, the unit consists of a base, motor drive, counter, and loading platform. Included are a special cup pedestal and plate for forming conical cavities in each end of the specimen. The cavities formed locate the specimen in the center of the platform and guide the tip of the cone penetrator.
The Dietert Company founded by Harry W. Dietert in 1922 is now part of DIETERT Foundry Testing Equipment Inc. Throughout the years, Dietert Laboratory instruments have been used worldwide in controlling sand quality for the production of high quality castings. Dietert moisture testing, analytical and mechanical test equipment have set the control standards for a wide range of industries and products.