Impact Resistance of Steel from Derailed Tank Cars in Minot, ND

摘要

On a freezing morning in January 2002, a freight train derailed in Minot, North Dakota, causing five tank cars that carried anhydrous ammonia to catastrophically rupture. The event led to immediate release of over 142,000-gallons of anhydrous ammonia, posing a great hazard to the local community. Charpy V-notch impact testing of samples removed from the shell portions of several catastrophically fractured tank cars showed that the impact resistance of the steel for each tank car varied greatly. The NTSB metallurgical investigation also determined that brittle fractures and low impact resistance of the steel contributed to the catastrophic fracture of the tank cars. The paper discusses the results of Charpy V-notch impact testing of selected samples from the catastrophically fractured tank cars and addresses options for improving the construction of future tank cars.