Design of flanges using VIII Div. 2 for Reactor with T>800¬F

[labastidasjose]

Gentlemen,

I am now designing a Reactor with Design Temp of 850F using Section VIII Div. 2. For the design of flanges i am facing problems because Table 3 of Section II-D limits the maximum Use Temperature of Bolts to 800F for all the materials. Same table provides temperatures upto 1500F for Section VIII Div. 1. I am trying to find a paragraph in the Code allowing to use Section VIII Div. 1 vealues (like for external pressure), i have checked Interpretations and Code Cases as well and found nothing.
Any idea to help me?

Regards,

Decode.

 

[gr2vessels]

Unfortunately, you cannot use the maximum design temperature limits of div 1 in div 2 design for bolts. You seem stuck with 2 options: -using div 1 design for the reactor or lower only the flange design temperature to 800F, particularly if you can use the flange uninsulated (exposed to the atmosphere). Take note that the internal design temperature may not need to be extended to the flanges exposed to the cooler environment.
Cheers,
gr2vessels

 

[decode]

gr2vessels, thanks a lot for your reply, I already found the solution. See Code Case 2655 (Suplement 3 of 2010)

regards,

Decode