Читать книгу Coal-Fired Power Generation Handbook - James Speight G., James G. Speight - Страница 61

Roll crushers are size reduction devices that shear and (or compress) the material that is to be reduced in size. The single-roll crusher is a popular piece of equipment and primarily consists of a heavy cast iron or steel fabricated frame on which are mounted the crushing roll and the stationary breaker plate. The breaker plate is provided with renewable wear plates bolted to the breaker plate. The roll usually has a series of long teeth spaced at intervals and various short teeth covering the entire crushing surface. The coal is squeezed between the revolving roll and the breaker plate. The long teeth act as feeders and also penetrate the lumps of coal, splitting them into smaller pieces, while the smaller teeth make the proper size reduction (Roman, 1967).

Double-roll crushers consist of two rolls that rotate in opposite directions. A double roll crusher can reduce run-of-mine coal (maximum top size 36 inches, 0.9 m) to a product with a top size in the range of 14 inches (350 mm) to 3/4 inch (19 mm). The roll size can vary from 12 x 18 inches to 60 x 60 inches and capacity may vary up to 2,000 tons/hour. Double-roll crushers generally produce minimal amounts of fines (Roman, 1967).