Design temperature and relieving temperature

[Leclerc]

As I understand, within the vessel Codes there is an allowable accumulation ( say 10%) which may be applied to design pressure/ MAWP. Also, where relief valve set pressure is set at this design pressure/ MAWP and there is overpressure of, say, 110% of set pressure, the valve relieving pressure is at the vessel allowable accumulation pressure.

Now to temperature:
For a system where vessel contents have a temperature coincident with pressure at the bubble point;

What should the vessel design temperature be? Should it be the bubble point at the design pressure/ MAWP, or should it be the bubble point at relieving pressure ?

 

[BigInch]

Why set design pressure at the bubble point?

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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

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