NIOSHTIC-2 Publications Search

Energy Absorption Systems for Mine Cages. Final Report, Vol. 1. Free Fall Testing of Single Tooth Safety Dogs on Keruing Guides.

Penning FA; Sorensen DR; Robertson DW
For Reference Only At Bureau Libraries :214 pages
A number of highly instrumented free-fall tests were performed on an arrestment system for a human cage in a vertical shaft. A single- tooth safety dog was used to stop on 4- by 6-in Keruing (Philippine mahogany) wet and dry wood guides. Twenty-seven free-fall tests were performed covering weights from 3 1/2 to 10 1/2 tons and hoisting velocities from 850 to 1,350 ft/min. Average g loads were measured from a low of 0.6 to a high of 3.4. The electronic instrumentation included piezoelectric and seismic mass accelerometers, strain gages on structural and mechanical elements, load cells in the guides, and distance measuring. Computer analysis was used to correlate with experimental measurements used to calculate stress. A statistical analysis gave no indication that the velocity or area affected the wood-crushing stress. The instrumentation revealed a chatter occurring during the stop that imposes loads much higher than the average g load, as shown by the accelerometers, strain gages, and load cells.
Publication Date
Document Type
CP; Final Contract Report;
Fiscal Year
Identifying No.
OFR 133(1)-81
NIOSH Division
Source Name
For Reference Only At Bureau Libraries
Performing Organization
Colorado School of Mines
Page last reviewed: October 29, 2021
Content source: National Institute for Occupational Safety and Health Education and Information Division