Dear All,

May anyone help advise the indicators configuration for boiler drum level indicating gauges in power plants in North America.

1). In one drum indicating, what is the most popular prortfolio of different kind of indicators, such as how may gauges glass, how many DP indicator, or Electrode Indicators, oe some other kind of indicators. And any advise about the manufacturer of each kind of indicators?

2). About gauges, it seems it need maintence frequently, so is it still be used in most power plants? Or they use some other independent to replace it and just keep it at serviceable state according to ASME codes.

3). About the maintence of gauge glass: how frequently it would need clearance, and what is the general expected life time of gauge glass. Also any advise of gauge glass manufacturer.

Thank you for your help and best wishes to all
Paul

Paul, to answer your question,

1). For the drum levels we have two methods of indication..obviously the more the better. We have a level site glass as well as DP transmitters (for feedwater control) and local gauges. Transmitters such as those made by Emerson Rosemount are typical and what is most popular.


2). Would recommend setting up a Preventative maintenance schedule to calibrate the transmitters and gauges. Since this is a critical instrument, the more aggressive the better. We have our calibration intervals set up semi-annually for the drum level indications.

3). Glass? it typically varies site to site.. if your water quality is great, you wont need to replace or clean your site glass as often. poor water quality will start fogging the level indicator.
I hope this helps. thanks

What Paul said, AND, I cannot say enough good things about the electrode type such as hydra-step or eye high indicators. These typically operate stand alone and independent of DCS systems which is a GOOD THING. They are absolutely worth every bit of cost to purchase and maintain. Very reliable.

They work as well on conventional drum boilers and multiple drum HRSG applications.