Determination of Gasket Effective Width Based on Leakage

The concept of the effective gasket width is used in the ASME code for flange designs to account for flange rotation. Its origin has never been revealed and it is suspected that only limited experimental testing was conducted for verification. In addition, with the new design rules based on the new gasket constants obtained from ROTT tests conducted on rigid platens, there is a need to revise the effective gasket width formulas. This paper presents some work development conducted under the auspices of the PVRC and related to the investigation of the effect of the non-uniform gasket contact stress due to flange rotation on the leakage behavior of sheet gasket materials. A experimental investigation coupled with some numerical work were conducted to determine the effective gasket width and its variation with gasket type, flange flexibility and load.