API-934

[khati]

Hi ,

Can anyone tell me why do we use API-934, is it an additional requirement for 2 1/4Cr-1 Mo & 3Cr- 1Mo materials.
Can it be waived off..?

Thanks,

 

[vpl]

Khati,

When I googled "API 934" I found the following excerpt from IHS (which is a service that provides access to standards):

"This recommended practice presents materials and fabrication requirements for new 2-¼Cr and 3Cr steel heavy wall pressure vessels for high temperature, high pressure hydrogen service. It applies to vessels that are designed, fabricated, certified and documented in accordance with ASME Code Section VIII, Division 2, including Appendix 26, Mandatory Rules for Cr-Mo Steels with Additional Requirements for Welding and Heat Treatment and ASME Code Case 2151, as applicable.

Materials covered by this recommended practice are conventional steels including standard 2-¼Cr-1Mo and standard 3Cr-1Mo steels, and advanced steels including enhanced 2-¼Cr-1Mo, 2-¼Cr-1Mo-¼V, 3Cr-1Mo-¼V-Ti-B, and 3Cr-1Mo-¼V-Cb-Ca steels. The interior surfaces of these heavy wall pressure vessels may have an austenitic stainless steel weld overlay to provide additional corrosion resistance."

In regard to your question about whether the standard can be waived off -- it would seem to me that would be between you and your customer.


Patricia Lougheed

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