amse b31.3 - stress ratio acc fig. 323.2.2B: documentation in the papers?

[demser]

Hi,

asme b31.3 fig. 323.2.2B allows application of low-T carbon steel below -48°C if the requirements on Stress Ratio are met.
But how is this "translated" into the documents, e.g. pipe class, or for ordering, or for documentation to a Notified Body?
In other words: How / where to fix it in words that an LTCS-made pipe can be operated at certain T below -48°C but only up to a certain stress ratio?
How is this done practically in the papers?

Thank you very much,
Reinhard

 

[XL83NL]

Good question. I think that for a notified body, the results of a stress analysis would need to be documented and provided in order to show compliance with a design code, and justify the waiver for Charpy V-notch testing. However this doesn’t waive the PED requirements probably, so if this is for PED work, it can be quite a challenge.
For other documents, such as a line class or pipe spec document, I’d make a note indicating this waiver.

Is such waiver available in EN 13480-2?

Wheee are you located? Is this for piping in the EU?

Huub

 

[demser]

Hi XLl83NL,
thank you for feedback.
My office is in the EU but design is - in this case - according to ASME.
This was a more general question, referring to piping and equipment. Also ASME BPVC allows this reduction in temperature if the stress is reduced.