Principle analysis of blind flange sealing

Blind flange are usually used with flange gaskets, but wear occurs after a long time of use. This is due to the creep relaxation of sealing gaskets and bolts, which makes the residual stress on gaskets decrease gradually, and the sealing reliability of Stainless Steel B16.5 Class 300 Forged Blind Flange decreases gradually, and eventually leads to leakage failure. Therefore, we must understand the principle of stainless steel blind flange.

　　The main function of blind flange joint in pressure vessel and pressure pipeline is connection and sealing. The failure of blind flange is not due to strength problem, but due to the combined moment of bolt load, gasket reaction force and medium pressure, the deformation is caused by insufficient stiffness, which makes the pressure of gasket uneven, resulting in leakage of blind flange. Therefore, controlling the stiffness and deformation of blind flange is the key to flange.

　　In addition, because the factors involved in load and deformation of blind flange are relatively complex, it can only be indirectly reflected by experience and blind flange stress calculation for a long time. The calculation method of blind flange stiffness has been included in foreign codes, while the standards and regulations of vessels in China are formulated to ensure the safe operation of pressure vessels, and the safety of pressure vessels has become the goal. A pronoun for preventing strength failure or brittle fracture. Therefore, the requirement of blind flange material and the choice of gasket are the important guarantee of sealing.