Sealing principle of stainless steel flange for pressure vessel
When the pre-tightening force is applied to the stainless steel flange bolts, the piao bolt presses the gasket through the flange ring, forcing the flange gasket to produce compression deformation. When the Piao bolt force reaches a certain value, forcing the stainless steel flange sealing surface and gasket on the four convex plane filled with the gasket deformation, which prevents the fluid media leakage created initial sealing conditions. At this time the Gasket unit effective sealing area of the pressure on the gasket is called the initial seal pressure. When the equipment or piping under pressure, the bolts are stretched by tensile stress, the flange sealing surface in the direction of separation of each other, the sealing surface and the gasket between the pressure drop, gasket compression decreased, pre-tight seal pressure drop. If the gasket has enough resilience, the deformation of the gasket can compensate the bolt and sealing surface separation value, and so that the pre-tight seal ratio pressure only down to not less than the working seal pressure, the flange still maintain a good sealing state. Conversely, such as the rebound capacity of the gasket is insufficient, the seal is lower than the pressure to work seal below the pressure, or even the sealing mouth re-emergence of the gap, the seal fails.