Sealing Performance of Pipe Flange Connections

In these environmentally sensitive times, it is very important to reduce the amount of gasses released into the environment from pipe flange connections. The design procedure in which the tightness of the joint is used as a design parameter, therefore, must be established for the pipe flange connection. In this study, sealing performance of the pipe flange connection is examined by conducting both the finite element simulation taking account of nonlinear stress-strain relationship of the gasket and the leakage test using nitrogen gas. The analytical objects are the pipe flange connections with the compressed asbestos sheet gasket, in which the gasket width and flange thickness are varied for the purpose of changing the amount of flange rotation. It is concluded that the leak rate of the pipe flange connection largely depends on the maximum gasket contact stress remained when the internal fluid is pressurized. The validity of the axisymmetric finite element model of the pipe flange connection is also demonstrated by comparing numerical and experimental results of the flange rotation angle.