Base on our investigation,the current level measurement system can’t indicate the real level as the working environment inside and outside the drum is totally different which will cause big deviation.
And the water inside the drum is unsaturated as the feed water input. When the drum pressure is 1400psi, the deviation is up to 2 inches.
And when the drum pressure is beyond 2000psi, the deviation is up to 4 inches. Much higher drum pressure, bigger deviation and less safety. There is one direct way to check the problem which is opening the drum to check the water mark during outage period.
The high water level and low water level operation will cause big accident and MFT for power plants which are the hidden danger and can lead to big loss for the power plant.
We do hope more and more power plants can realize that and cares their boilers.
Any questions or disagreement, welcome to discuss.