This report presents an analysis of the results obtained in two tests of propane-laden DOT class 112/114A340 tank cars completely immersed in all-enveloping fires generated using JP-4 fuel. In the first test, an uninsulated car (RAX 201) ruptured at a pressure of about 335 PSIG after 24.6 minutes exposure to the fire. The safety valve incorporated on this car limited the maximum tank pressure to less than 350 PSIG, even in the all-enveloping fire. However, a rise in the temperature of the unwetted upper section of the steel shell to about 1200 degrees F precipitated rupture when the tank was about half full of liquid propane. In the second test, car RAX 202, insulated with a spray-on thermal protective coating, ruptured after about 93.7 minutes exposure to fire. With a heating rate averaging about 12,100 btu/hr/sq ft (43% of the 27,650 btu/hr-sq ft average from the first test), the longer time to rupture in this test is not solely due to insulation, as lower fire temperatures and other variables played an important part. As in the first test, rupture was precipitated by a rise in unwetted shell temperature to levels at which the shell strength could not withstand even the reduced tank pressures. As well as can be determined, it appears that the shell failure was initiated in an area which contained flaws or non-uniformities in the insulative coating.

  • Supplemental Notes:
    • An RPI-AAR Cooperative Program. Railroad Tank Car Safety Research and Test Project.
  • Corporate Authors:

    Railway Progress Institute

    801 North Fairfax Street
    Alexandria, VA  United States  22314

    Association of American Railroads Research Center

    3140 South Federal Street
    Chicago, IL  United States  60616
  • Authors:
    • Manda, L J
  • Publication Date: 1975-12-12

Media Info

  • Features: References;
  • Pagination: 114 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00130841
  • Record Type: Publication
  • Source Agency: Railway Progress Institute
  • Report/Paper Numbers: RA-11-6-31
  • Files: TRIS
  • Created Date: Apr 7 1976 12:00AM