Steam Boiler - overfill trip protection essential ? 1

[jamesbanda]

dear sirs,

we are buidling a new facility. our current boiler vendor at this stage has not proposed boiler overfil protection from excess level. we have a fire tube boiler.

We are recommending it based on our internal safety study.

I'd like to validate that this is normal pratice.

We believe level overfill risks water hammer and severe pipework damage - hence we should have protection...

 

[fjm3188]

Overfill protetion is legislated in some areas. In Ontario Canada, it is a provincial requirement that high water level shutdown be in place to prevent the burner from operating if the water level is 25 to 50% over the operating hash mark on the feedwater control.

You are aaabsolutely right in assuming damage to piping, fittings and joints through excessive water hammer. In addition, if you are using more than one boiler on the same header, insure stop and check valves are installed on the steam outlet of each boiler to prevent flooding of an unfired boiler.

 

[fjm3188]

In addition to my first reply, adequate area must also be maintained at the top of the steam boiler for proper steam separation giving you a higher quality "dry steam". (manufacturers' words, not mine.)

 

[jamesbanda]

Do you know which boiler code requires this overfill protection ?

 

[psafety]

NFPA 85