Feedwater Heater Vent sizing 1

[jsteverm]

I'm looking for a rational explanation of the orifice sizing for the operating vent of feedwater heaters. I have seen sizing criteria stated as 0.5 to 1.5 % of extraction steam flow but I don't know where it comes from. HEI doesn't have a criteria that I could find.

 

[samuelliu]

The last sentence of 2.13 of HEI Standard, page 11, might be the answer to your question.

Regards,