Development of a Quiet Rock Drill. Volume 1 - Evaluation of Design Concepts.
NTIS: PB 283 774 Available for Reference At Bureau Libraries :95 pages
This report describes the results of a study to evaluate new design concepts for percussive rock drills that will result in quieter machines. It is shown that by incorporating such features as an efficient muffler, a plenum chamber integral with the machine body, and shroud tubes around the drill rods, etc., noise levels are reduced from about 114 decibels, a-weighted network (dba) to about 95 dba with very little change in drilling performance.
CP; Final Contract Report;
NTIS Accession No.
NTIS: PB 283 774 Available for Reference At Bureau Libraries
Ivor Hawkes Associates