Flange gaskets are used to create a static seal between two flanges faces, at various operating
conditions, with varied pressure and temperature ratings. A gaskets fills the microscopic spaces
and irregularities of the flange faces, and then it forms a seal that is designed to keep liquids and
gases. Correct installation of damage-free gaskets and demage-free flange faces is a requirement
for a leak-free flange connection.
If it would be technically possible, in order to manufacture flanges perfectly flat and smooth, and
perfectly compatible with one another under all operating conditions, a gasket would not be
necessary. But in normal practice it is not possible, because flange connections under any circumstances should be made. Small impurities and a small bit of dirt, is in practice not be
avoided and therefore it is necessary to use a gasket.
Types of gaskets
Materials for gaskets can be divided into three main categories: