The slightest Vacuum on a Boiler
The slightest Vacuum on a Boiler
(OP)
I've noticed from superheater outlet steam header pressure trending, that I have a slight vacuum on a water boiler that produces superheated steam. So far in previous 2 years I have found about 5 days where the boiler was on standby and my pressure was a 6 min avg of -0.4-psig to -0.01-psig. On these 5 particular days these readings were over 1 hour to 3 hour time periods. I understand we want to be above atmosphere in the boiler. Does anyone think this slight vacuum can cause extreme localized pitting in the superheater tubes?




