Principles of naval engineering - Historic Naval Ships Association

Chapter 10- PROPULSION BOILERSFuel Oil BurnersAlmost all fuel oil burners used on navalpropulsion boilers are mounted on the boilerfront. Special openings called burner cone openingsare provided in the furnace front for theburners.The two main parts of a fuel oil burner arethe atomizer assembly and the air register assembly.The atomizers divide the fuel oil intovery fine particles; the air registers permitcombustion air to enter the furnace in such away that it mixes thoroughly with the finelydivided oil. In addition to the atomizer assemblyand the air register assembly, a fuel oil burnerincludes various valves, fittings, connections,and (on new construction) burner safety deviceswhich prevent spillage of oil when an atomizerassembly is removed from the burner while theburner root valve is still open.ATOMIZERS.— Three main kinds of atomizersare now in use on naval boilers. Straightthrough-flowatomizers are used on most boilers.Return-flow atomizers are used on many ofthe newer ships, particularly those equipped withautomatic combustion controls. Steam-assistatomizers are used on boilers in some of thenewest ships.A fuel oil burner with a straight-throughflowatomizer is shown in cross section infigure 10-10. Figure 10-11 shows how burnersof this type look when installed at the boilerfront.INNER CASINGOUTER CASINGAIR DOOR HANDLESTATIONARY^!AIR FOILSGOOSE NECKBURNER CONE OPENING |,Hi-YOKEDISTANCE PIECEMOVABLE AIR DOORSINNER CASINGBURNER(SIDE VIEW)OUTER CASING(BOILER FRONT)BURNER BARRELBURNER COVER PLATEAIR DOOR HANDLEATOMIZER VALVEBURNER(FRONT VIEW)38.69Figure 10-10.— Cross-sectional view of fuel oil burner with straight-through-flow atomizer.241