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Design of a Compact Muffler for a Jumbo Drill.
Visnapuu-A; Lay-SE; Martin-JR; Schwaneke-AE
NTIS: PB 293 282 :12 pages
The Bureau of Mines, as a part of its goal to minimize occupational hazards associated with mining and mineral processing operations, has developed and field tested a compact exhaust air muffler for mechanized, jumbo-mounted pneumatic rock drills. The muffler is constructed of 1/8-inch sheet steel and has nominal dimensions of 1 3/4 by 9 by 13 inches. A directed air passage, flexible neoprene baffles, and an expandable slit-type outlet are incorporated to reduce drill exhaust air noise and eliminate muffler icing. Field tests in actual mining operations showed a 15-dba reduction in exhaust noise and an 8- to 12-dba reduction in overall drilling noise with no icing problems or decrease in drill performance. Data are presented on muffler construction, laboratory, and field test results.
IH; Report of Investigations
NTIS Accession No.
NTIS: PB 293 282
Page last reviewed: March 11, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division