H2S resistent material

[FrankDNT]

dear all,
we are planning the design of a small unit where we will flow a gaseous stream of H2S (purity from 40% upto 80%) at variable temperature (from 50°C upto 500°C).

Do you have any suggestions about the selection of material for both piping (max P = 6 barg) and gaskets/sealants for thread connections?

thanks in advance
Francesco

 

[flexibox]

You cannot find an Oring to do the Temperature range of 50C to 500C. This is high temperature so you will need to use Graphoil gaskets and spiral wound gaskets. If you are using Mechanical Seals then you will need a Metal Bellows and I recommend a Dual Pressurized seal with API Plan 53B. There are other options to pressurize seals like Plan 53A & 53C but I believe that 53B is a better solution.

Use NPT & Flange connections

trust this helps

 

[FrankDNT]

Thanks a lot for your suggestion, I was thinking to some kind of "special" polymeric gaskets but the graphoil solutions sounds much more reasonable....

regards
Francesco

 

[HydraulicsPE]

There is a metal based O-ring shaped seal that has temperature ratings to 850C. Link follows:

http://www.tss.trelleborg.com/com/

http://www/media/downloads/catalogs/wills_rings_gb.pdf

 

[FrankDNT]

thanks a lot for the link, I'll go through the documentation carefully.

 

[Pumpone]

Double mechanical seal plus plan 54 or Double mechanical seal with contact and non-contact face with gas barrier should resolve the problem .
Go to Flowserve Mechanical seal contact....

 

[FrankDNT]

thanks also for this suggestion....so basically it seams the "plan" seal is the most indicated....I'll get deeper on this possibility.

Francesco