Normally the MAWP of nozzles is determined by the reinforcement of the opening in the shell rather than by the hoop stresses in the nozzle neck. Adding additional reinforcement is not expensive.
Checking mechanical integrity of a vessel after it has been in service is simple enough if the shell...
Allowable stresses in the ASME Code for carbon steel at elevated temperatures (above 700 or 800 degrees F) are based on the Creep to Rupture Criteria (100,000 hrs.). Creep is the result of long term exposure to elevated temperatures and would not necessarily be applicable for the fire case.
If...
You will need to determine the leg dimension corresponding to the throat dimension you need and specify the leg dimension on the weld symbol. The leg dimensions are easier for the welder and inspector to work with.
When considering weather to use seamless or rolled and welded plate, you should check the tolerances in the material specification. I think the material specs you referenced have a plus or minus 12 1/2% tolerance for seamless pipe whereas the rolled and welded plate will have a much lower...
