Effect of Ventilation on Conveyor Belt Fires.
Proc Symp on Safety in Coal Mining Pretoria Rep of So Africa 1987 Oct; :15 pages
This paper describes full-scale fire tests of conveyor belts conducted by the Bureau of Mines to determine the effect of airflows of 1.5 and 4.1 M/s on fire development and propagation. The tests were performed in an aboveground fire gallery approximately 27 m long. Rubber and polyvinyl chloride (pvc) belt samples 9.1 M long were placed on top rollers of a belt conveyor frame and instrumented with thermocouples to measure flame spread rates. Additional sensors monitored air temperatures and major combustion products. The ignition source was a liquid fuel tray fire located just below the upstream edge of the belt sample. Three different styrene butadiene rubber belts ignited and completely burned at both airflow rates. The flame spread rates, downstream gas temperatures, and co and co2 concentrations for each belt were less at the 4.1-M/s than at the 1.5-M/s airflow. Two pvc belts burned at the lower airflow with rapid flame spread rates, but at the higher airflow the same belts did not propagate flame, and damage was limited to the ignition region. A pvc belt and a chloroprene rubber belt did not burn at either airflow. The overall results indicate that for these test conditions, the higher airflow reduced the hazards of propagating conveyor belt fires.
Proc Symp on Safety in Coal Mining (Pretoria, Rep. of So Africa) Oct, 1987, 15 PP.