Technical Reports

Aluminum Tank Car Puncture Resistance Evaluation

  • 01
  • Jul
  • 1992
AUTHOR: Federal Railroad Administration
SUBJECT: Hazardous Materials
KEYWORDS: Tank Car; Head Shield; Hazardous Material; Train Collision; Puncture Resistance; Accident Survivability
ABSTRACT: Experimental studies to maintain the safety of transporting hazardous material by rail have been extended to evaluate the effectiveness of steel head shields for the protection of the contents of DOT Type 111 aluminum tank cars. These studies comprised a series of full- and 1/5-scale model tests based on prior tests conducted on DOT Type 105A500W (chlorine) tank cars and DOT Type 112J340W tank cars. Design parameters were varied to establish the sensitivity of puncture resistance to head and tank head shield thicknesses, internal pressure, and temperature. The test to demonstrate puncture resistance, specified in Title 49, Part 179, section 179.105-5 of the Code of Federal Regulations, requires a threshold speed of 18 mph. The tests conducted in this study were intended to demonstrate the puncture resistance of various head configurations of a standard DOT Type 111 aluminum tank car, the puncture resistance of DOT Type 112/114 (propane) tank cars and DOT Type 105 (chlorine) tank cars and to investigate the relationship between the 1/5 and full-scale impact models. The results of the full-scale tests showed that bare aluminum heads had very low resistance to puncture and that heads protected by a 1/2-inch thick steel head shield had a puncture resistance of 16.5 mph. The 1/5-scale tests with steel chlorine and propane tank car heads demonstrated a much greater resistance to puncture than the aluminum tank car heads. The 1/5-scale tests showed that puncture resistance is strongly influenced by shield thickness and internal tank pressure which is affected by the temperature of the gas within the tank car.