A Leakage Rate Prediction Model for Flange Connections Based on the Relative Deformation of Gaskets

Flange connections are widely used in industries such as petrochemicals and nuclear power, where they encounter complex mechanical and thermal loads, making them potential sources of leakage. Leakage not only affects the continuity of production but can also lead to significant economic and personnel losses in severe cases. This paper proposes a leakage rate prediction model for flange connections based on the relative compressive deformation of gaskets, while also accounting for the effects of gasket creep. The parameter values for the leakage rate prediction model were obtained by fitting the data from the gasket sealing performance tests. Leakage rate testing was conducted on a DN50 flange connection device under internal pressure and static bending moment loads, with the corresponding leakage rates obtained through a pressure drop method. It was found that, under the same static bending moment, the leakage rate decreased as the pressure was reduced; conversely, under the same internal pressure, the leakage rate increased with an increase in bending moment. Numerical calculations were performed to analyze the deformation of the gasket in flange connections under different external loads, considering the effects of gasket creep, leading to the calculation of the relationship curve between leakage rate and medium pressure. A comparison between the simulated predicted leakage rates and experimental values showed good agreement, validating the accuracy of the leakage rate prediction model.