Dears,

Can spiral wound gasket-carrier ring 'high recovery' type with two spiral wound gaskets placed in two sides of a metallic ring - be used in H2rich HC service ?

regards,

sam

Dears,

Background of the above query is that we are checking the large bore flange leakage by Caesar-II's procedure for spiral wound gaskets while we are using carrier ring 'high recovery' type gasket with two spiral wound gaskets placed in two sides of a metallic ring & the service is H2richHC.

Is this approach enough for large bore flange leakage of H2 service ?

regards,

sam

Have you considered using RTJ joints ?

It isn't about a future application. So, RTJ joint can't be considered.

regards,
sam

sam,

Hydrogen has the ability to find the smallest of leak paths or porosity in materials. So the installation technique, flange face finish, or the filler of the spiral wound gasket might invalidate the CAESARII flange leakage analysis. Yes, the 'high recovery' spiral wound gaskets could work with the metallic ring, however there are other considerations along with the piping loads, bolt torques, and gasket compression area.

Request recommendations from the gasket vendor for filler materials in the spiral wound gasket along with bolt torques and any other installation guidelines. Inform the gasket vendor of the pressure class of flanges, bolt materials used, along with the hydrogen service conditions of pressure and temperature.

Some users of spiral gaskets select flexible graphite filler material and then wrap the spriral wound gasket with more flexible graphite tape before installing into the flange joints. If the service temperature is compatible with Teflon filler material, then the gasket vendor might have comparison of hydrogen leakage with different filler materials.

Thank You, Sir, for the reply.

Yes, the gasket has flexible graphite as filler material. Gasket vendor is very renowned; bolt torques & installation procedure is according to their suggestion.

regards,

sam