One of the important features in designing a gasketed flanged joint is the ability to predict and control leakage from the joint. Extensive gasket leak tests both at room and elevated temperatures have been conducted in various laboratories under the sponsorship of the PVRC Bolted Flanged Connection (BFC) Committee. However, many of these laboratory tests were conducted using a scaled model with rigid plattens and under simulated conditions. To complement those data obtained from laboratories, several projects related to leak tests of full scale flange were conducted under the sponsorship of the PVRC BFC Committee. This bulletin presents the results of leak testing of a 24-inch Class 150 raised face weld neck flange subjected to internal pressures. Flexible graphite sheet with and without tangs, spiral wound with flexible graphite filler, corrugated stainless steel with flexible graphite on each side and aramid fiber gaskets were tested.

Comparison of the experimental leak-rates from this study and those predicted by the PVRC gasket constants based on the ROom Temperature Gasket Tightness Test (ROTT) was also made. The PVRC gasket constants, which were derived from numerous laboratory leak tests, are the key parameters for the new ASME design rules for bolted flanged joints.