B16.5 - 904L RFSO Flanges

[marty007]

Hello,

I am working on two jobs being fabricated from 904L (N08904) material (B31.3, VIII-1), and the nozzles should have 904L B16.5 RFSO flanges.

Per ASME B16.5 (2017), the listed forging spec for this material is A-479. Unfortunately, when we request quotes from vendors, they all regret on A-479 and offer instead A-182.

This whole mess of 904L specifications came up in 2013 under the following thread: Thread 342249

At the time, I wrote to the code committee requesting that the accepted forging spec be changed to A-182 N08904. Unfortunately, I received no response, and the latest edition of B16.5 (2017) is still listing A-479 as the acceptable material spec for 904L forgings.

Two questions:
[ol 1]
[li]Is there any way to substitute A-182 N08904 material for A-479 N08904 material and still be in compliance with ASME B16.5 for use in B31.3 and VIII-1?[/li]
[li]I have sent maybe 5 interpretation requests to ASME code committees over the past 5 years (VIII-1, B16.5), and have never once received a response. I am sending them via the instructions for technical inquiries at the front of the code books. Is there a more effective way of requesting interpretations, because I really don't feel like I'm being supported here...[/li]
[/ol]

 

[XL83NL]

1. No idea. However, why not try to use lap joint flanges, where you use 904L lap joint stub ends to B16.11 with a stainless or carbon steel B16.5 lap joint flange?
2. Ive successfully issued interpretations or code request in the past, and send them to customercare@asme.org. They usually got picked up by Riad Mohamed for B31.3 work. For section VIII work it usually was someone else. Are you sure the email responses didnt end up in your spam?