A variety of test methods utilizing the Naval Ordnance Laboratory (NOL) type filament-wound ring specimen have been evaluated for their relative merits in determining hoop tensile strengths. The methods studied were the “standard” NOL split disk test, the NOL hydraulic test, and the split disk test using a notched ring specimen. Comparisons of 0.060-in. and 0.125-in. thick ring specimens were made for each of the three test methods, and the effects of three epoxy resin systems were also noted.

The notched ring test, the hydraulic test, and the “standard” split disk test yielded hoop tension test values of decreasing magnitude in the order indicated. Thinner-walled rings for each method gave higher and more consistent results than heavier-walled ring specimens. The type of epoxy resin system used for winding had no apparent effect on the relationship of the results of different test methods.