Code Approval of Composite Propane Cylinders for Indoor Use ...

Task 2 – Conduct Preliminary Composite Cylinder Fire TestingThe purpose of Task 2 was to conduct preliminary fire performance testing of the compositecylinder to provide background information to the Advisory Group and NPGA.Preliminary TestingBattelle and ThermDyne performed preliminary fire testing for the project from February 17 toMarch 3, 2005, at the Mining Resource Engineering Limited’s test site north of Kingston,Ontario, Canada. Six conventional steel cylinders, 18 two-piece, linerless composite cylinders,and 11 one-piece, lined cylinders were tested in various fire exposure conditions, orientations,and fill levels. All cylinders were nominally 20 pound capacity (45 to 47 pound water capacity).The three fire conditions that were used in the preliminary fire tests to mimic a liquidhydrocarbon pool fire are described in Table 2 and a summary of the test plan is provided inTable 3.In the preliminary testing, the test cylinders were oriented either vertically (Figure 1) orhorizontally (Figure 2). In the horizontal position, the flame was directed at the side (as shown inFigure 2), at the valve, or at the base for the different tests.No steel cylinders ruptured during the testing. The relief valves opened between 375 and 400psig. Some relief valves re-closed above 300 psig, and some didn’t re-close until 100 psig. In alltests, the steel cylinders emptied before the cylinder walls softened and thinned enough torupture. One steel cylinder did show a bulge (Figure 3).When tested vertically and with a nominal fill level of 75 percent, the two-piece, linerlesscomposite cylinder did not fail (Figure 4). During these tests, propane began to leak around thevalve-cylinder connection and diffused through the cylinder walls after reaching peak pressuresbetween 98 psig and 118 psig. Figure 4 shows that the propane continues to permeate throughthe wall even though the cylinder pressure was essentially zero gage. The outer protective jacketwas consumed on all composite cylinder tests.Composite Propane Cylinders 9 February 2007for Indoor Use — Phase IIBattelle