MECHANICAL SEED CLEANING AND HANDLING
Screen Numbering System The size of a round-hole screen is indicated by the diameter of its perforations. Perfora- tions larger than 5V2/64ths of an inch are measured in 64ths. Therefore, a 1-inch round- hole screen is called a No. 64, a 1/2-inch screen is a No. 32, and so forth. Screens smaller than 5i/2/64ths of an inch are measured in fractions