Analysis of fire-induced ruptures of 400-L propane tanks

A series of fire tests were conducted to study the thermal rupture of propane tanks. The tests involved 400-L ASME automotive propane tanks filled to 80 percent capacity with commercial propane. The tanks were brought to failure using torches and pool fires. The resulting thermal ruptures varied in severity from minor fissures, measuring a few centimeters in length, to catastrophic failures where the tank was flattened on the ground. The catastrophic failures would typically be called boiling liquid expanding vapor explosions (BLEVEs). The objective of this work was to develop a correlation between the failure severity and the tank condition at failure. The deformed propane tanks were measured in detail and the extent of deformation was quantified. The tank failure severity was found to be a complex function of a number of tank and lading properties at failure. This paper presents the measured data from the tanks and a step-by-step description of how the correlation was determined.