Tubesheet design temperature

[KarimElsaadany]

Hello everyone,
Is the tubesheet of a High Pressure Feedwater Heater designed based on the superheated steam temperature or the saturation temperature of the condensing zone?

 

[uglyspec]

It should be based on the design pressure indicated on the nameplate.

 

[Shashvat]

Hi KarimElsaadany.
I think it should be the higher temperature of the two, as the corresponding allowable stress and other corresponding entites would be lower for the higher temperature and hence the safer design.