Two marine steam boilers' operation
Keeping a slave boiler pressurized in a two boiler system
In a two boiler system its often a problem to keep
the slave boiler at operation pressure when the steam demand is low. This
problem does not appear when the vessel is loading or unloading in a harbor
since those operations normally need both boilers. On the other hand, when the
ship is at sea and only one oil-fired boiler is used then the slave boiler
tends to cool down far below the required stand by conditions.
installations will be unnecessary if you happen to have an
EGE, exhaust gas economizer.
The method has been used in many ships and the chief engineers are satisfied
with the result.
When bringing a boiler on-line with another boiler, ensure that the working
pressure is the same in both boilers and be sure to drain condensate from the
steam line, before cracking the valve, to avoid
water hammering. Let the steam line be heated up before the
steam valve is fully opened.