Thin-Metal Lined PRD 49-III Composite Vessels.

In this program a total of 22 - 8 in diameter PRD-49-3 filament wound vessels were evaluated for burst strength and fatigue performance. Eighteen vessels contained a 0.003 in 0.0762 mm thick 321 stainless steel liner for fluid containment while the remaining four had elastomeric liners. Six of the metal-lined tanks were burst tested at 70 deg F 21 deg C. The final vessel design with a metallic liner gave an average burst pressure of 2560 psi and an average performance factor PVW of 1.75 x 10 to the 6th inch. Twelve metal-lined vessels were cycled at strain levels equivalent to 50 and 75 of ultimate at 70 F 21 C All these vessels leaked in a relatively few cycles 20-60 cycles with failure occurring in all cases in the metallic liner. The thin liner would de-bond from the composite and buckle during depressurization. No composite failures or indications of impending composite failures were obtained in the metal-lined vessels.