Gaskets
Bolted flanges connections - Characteristics and components

In a bolted flange assembly, the gasket ensures the continuity of the pressure barrier by filling in the irregularities on the flange faces. In theory, if the flanges were perfectly rigid, flat, and perfectly smooth (zero surface roughness), no gasket would be necessary. In practice, surface imperfections, elastic deformations caused by loads, as well as temperature and pressure variations require the use of a gasket capable of adapting to these stresses while maintaining the assembly’s seal.

Gaskets can be classified into three main categories: non-metallic, semi-metallic, and metallic, each offering specific performance characteristics in terms of pressure, temperature, and chemical resistance. Their selection is based on standardized mechanical characteristics, notably the gasket coefficient