Design of a Quiet Rock Drill. A Feasibility Study Using Principles of Leavell Pavement Breaker.
NTIS: PB/274-402 Available for Reference At Bureau Libraries :41 pages
This report shows the feasibility of a quiet stopper for drilling roof bolts in coal mines. The work is directly applicable to pneumatic percussive rock drills. The report shows an oscillator based on patented leavell concepts which results in a vibration-free tool and noiseless exhaust. The dynamics of the oscillator are analyzed. Independant rotation of drill rod is provided by an air motor (screw expander), and flushing of cuttings is accomplished by an air ejector in a compact lower housing. The feasibility of no exhaust noise, low drill machine noise, and vibration-free casing is discussed.
CP; Final Contract Report;
NTIS Accession No.
NTIS: PB/274-402 Available for Reference At Bureau Libraries
Vast Research Company