Suitable steels for 20% H2S environment

[PaulEng]

Does anyone have any knowledge on suitable steels for manufacturing equipment for use in a 20% H2S environment? Normally I would use AISI 4140 limited to 22RC but not at this elevated level of H2S.
Thanks and regards,
Paul

 

[CoryPad]

SAE 4130 with 22 HRC is widely used for these conditions.

 

[TVP]

SAE 4130 modified by the addition of Mo (up to 0.75%) is often used at 22 HRC for these conditions. Mo confers additional corrosion resistance in both Cl- and H₂S conditions.