Soft Gaskets are used with flat-face and raised-face flanges in low and medium Pressure Class applications. Based on the inertness of the materials used, they can fill many chemical requirements, and be used up to very high service temperature.
Their fabrication is by either die-cutting or CAM cutting from several types of sealing sheet materials, such as: Compressed Fibre, Flexible Graphite, PTFE, Thermiculite®, Beater Addition, Solid or Cellular Rubber, Mineral Fibre Felt, Mica, Cork, etc.
For high temperature and pressure, thermo-mechanical cycles and shock, and in situations where the assembly procedures can not be adequately controlled, non-metallic gaskets can be reinforced with inner and outer rings of stainless steel.
For marine engine exhaust systems a specific typology of gaskets has been developed, called CENTISEAL, which allows the seal even in the presence of large and deformed flanges operating at very high temperature.