Oil in boilers feedwater
Beware of oil in the boilers feed water system.
The steam boilers on board in ships nowadays have become a less evident part of the engine room than they were in the old days. However, the steam boilers are still important parts of the system, especially if the main engines are running on heavy fuel oil that need to be heated. I dont want to go through the entire instruction book for the marine boiler but just point out one important matter.
As we all know, a very thin layer of oil on the surface of the boiler tubes
or any of the direct heated surfaces of a boiler might cause local overheating
of the material and possible damage to the boiler. What we maybe not know is
how very small quantity of oil it requires to get a dangerous situation. A tube
break in a fuel oil heat exchanger is very easy to detect, a simple detector in
the hotwell will manage that, but a small crack in a tube may cause you an even
more serious problem.
An oily ring inside the water gauge glasses at the water level is a serious warning.