Tanged graphite gaskets range of graphite sheet sealing materials are manufactured from highly pure exfoliated graphite flake, with/without a reinforcing metallic core with the standard product offering graphite with a carbon content of 98% whiles for nuclear purposes its 99.85%.
Tanged graphite gasket laminates by Goodrich Gasket are suitable for moderately high temperature/high pressure gasket applications with a wide range of media. Using mechanical means or certain adhesives, graphite foils can be attached to the reinforcing core.
These gaskets are used in demanding industries such as petrochemical/refining industries as a result of absence of any rubber or polymeric binders making their stress retention levels high. This in turn ensures that the gasket stress applied upon assembly is retained during service.
In chemical service industry, though graphite based products are resistant to most chemicals it is highly imperative to consider any possible reaction between chemical medium and reinforcing metallic core as graphite is susceptible to attack by nitric acid or sulfuric acid at certain concentrations and temperature.
Based on the temperature and concentration of oxygen present and the purity of graphite it may burn away getting converted to oxides of carbon. With a well bolted flange graphite burns away very slowly in contact with the oxygen from the inner edges of the pipes. Whereas, high temperature gasket applications of fluids sealed with no oxygen is influenced by the attack on graphite from the oxygen in the atmosphere surrounding the flange.
Due to the complexity surrounding the oxygen and temperature for graphite getting burnt away the Tightness Testing Research Laboratory [TTRL] on behalf of Pressure Vessel Research Council [PVRC] has recorded maximum service.
Tanged Insert Graphite Sheet
Temperatures for various periods of service life requirements and the same is offered from the graphite sheets by Goodrich Gasket as below: