ASME B31.8 Piping Spec

[Corgas]

I just came across a piping spec for underground Gas Pipeline - Sour Service (NACE MR0175/ISO 15156)designed according to ASME B31.8 -2007.

Design temps are -50F to 140 F.

Since I'm not familiar with B31.8 I started reading this document and on para 802.12 (b)it says:

"This code does not apply to piping with metal temperatures above 450 F or below -20 F.

Even though, proposed piping material ASTM A333 Gr 6 is good for this low temp it does not seem consitent with para 802.12 (b).

Should the design code be changed to ASME B31.3?

Thanks,

Corgas

 

[DLite30]

If you read further, it refers you to paragraph 812 which references ductile/brittle fracture control of the chosen pipe material at low temps...

Ask yourself which category your piping falls in:

B31.3 Process Piping: piping typically found in petroleum refineries, chemical, pharmaceutical,
textile, paper, semiconductor, and cryogenic plants, and related processing plants and terminals

B31.8 Gas Transportation and Distribution Piping Systems: piping transporting products which
are predominately gas between sources and terminals, including compressor, regulating, and
metering stations; gas gathering pipelines

 

[BigInch]

Read the first section of each code, "SCOPE", choose the appropriate code then use the appropriate pipe within the allowed temperatures for the material.

Let your acquaintances be many, but your advisors one in a thousand’ ... Book of Ecclesiasticus