NIOSHTIC-2 Publications Search
Tunneling Machine Research - Size Distribution of Rock Fragments Produced by Rolling Disc Cutters.
NTIS: PB 233 414 :40 pages
The Bureau of Mines used a linear cutting apparatus equipped with a 7-inch disk cutter to cut grooves in marble, limestone, granite and quartzite under a normal force of 7,000 lb. The size distribution of the muck for various grooves was determined through sieve analysis. A statistical search showed that weibull distribution describes the size distribution better than other available functions. Results indicate that fineness modulus, chip population, and dimension of the largest chip can be used as indicators of cutting efficiency. The results correlate with those obtained from the boring machines and other laboratory experiments. Application of the principles established through this work to the operation of boring machines is explained.
IH; Report of Investigations
NTIS Accession No.
NTIS: PB 233 414
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division