NACE requirements for Hydrogen Embrittlement?

[awhicker84]

Hi,

I'm in the API compressor industry (oil and gas). We use NACE MR0175 and MR0103 (deals with H2S cracking), but I was curious if there are any standards for hydrogen embrittlement. I came across a Polyeurthane compressor that has 10% hydrogen in the process. The engineer (many years ago) decided to spec out NACE MR0175 / MR0103 compliant material for the impeller. Today I had to approve a material change for something else on the unit and it made me wonder. The only problem I could see process-wise is hydrogen embrittlement, but I can't find any standards that deal with it. I did find a few research docs.

I ended up allowing 304 SS.

Cheers,

 

[mk3223]

Take a look of API RP941 which is the steel used in the H2 service at elevated temperature. It may be the one you are looking for.

 

[SJones]

Hydrogen does play a role in the H2S cracking mechanism for carbon and low alloy steels and some high strength corrosion resistant alloys; hence, it can be beneficial to specify requirements intended for H2S service. Since you are involved with the oil and gas industry, it might pay you to get hold of API RP 571 which will give you an insight into various damage mechanisms and the susceptibility of different materials to those mechanisms.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[awhicker84]

thanks a lot!

 

[blacksmith37]

It is primarily semantics; There are a dozen names for the hydrogen induced cracking of high strength steel at ambient temperatures. I suppose " embrittled" means it is ready to crack.