Abstract
The stresses in pipe flange connections with asbestos gaskets and non-asbestos gaskets subjected to internal pressure at room temperature are analyzed taking account of a hysteresis in the stress-strain curve of the gasket using axisymmetric theory of elasticity and a three-dimensional finite-element method (FEM) . The contact gasket stress distributions, the hub stresses and the variations in axial bolt force are examined in each pipe flange connection with asbestos and non-asbestos gaskets. The characteristics of the connections are demonstrated between asbestos and non-asbestos gaskets. Moreover, the amount of leakage is estimated using the basic gasket property obtained from JIS B 2490 and the contact gasket stresses obtained from the axisymmetric theory of elasticity and FEM. The estimated results are in a fairly good agreement with the experimental results obtained from the leakage tests, where spiral wound gaskets (SWG) are used. It is found that the differences in the contact gasket stress distributions between pipe flange connections with asbestos and non-asbestos gaskets are small. The sealing performance of the pipe flange connections with non-asbestos gasket is better than that with asbestos gasket at room temperature.
