Toc: Content: Marine Engineering Series, Page iiFront Matter, Page iiiCopyright, Page ivPreface, Pages v-viiAcknowledgements, Page xi1 - Historical development of the marine boiler, Pages 1-92 - Theoretical development of the marine boiler, Pages 10-173 - Tank type boilers, Pages 18-584 - Water tube boilers, Pages 59-1535 - Dual-fired boilers for oil and liquified natural gas, Pages 154-1646 - Composite boilers and exhaust-gas heat exchangers, Pages 165-2097 - Forced circulation boilers, Pages 210-2168 - Low-pressure steam generators, Pages 217-2329 - Superheaters and economisers, Pages 233-26410 - Materials used in construction, Pages 265-27711 - Boiler construction, Pages 278-33012 - Refractories and insulation, Pages 331-33513 - Boiler mountings, Pages 336-38114 - Boiler controls, Pages 382-40915 - Treatment of boiler water and feed water, Pages 410-43216 - Steam generation and boiler operation, Pages 433-46917 - Fire-fighting appliances, Pages 470-47918 - Water tube boiler surveys and repairs, Pages 480-52319 - Tank type boiler surveys defects and repairs, Pages 524-56420 - Certificates of competency, Pages 565-574Appendix, Pages 575-580Index, Pages 581,583-591
The boilers were also mostly used as heat-recovery boilers, from the exhausts of large marine diesel engines, as these operated at a lower temperature than a direct-fired boiler. Some were equipped as composite boilers, heated by exhaust gases when under way or with oil-firing when in port.
Where the boiler was arranged for composite firing, the central flue version was used with oil firing. Fired boilers sometimes included vertical water-tubes of more conventional form as well, to improve circulation. There could even be cross-tubes, as for the common vertical cross-tube boiler. A common form for ships had both inner and outer flues, with separate gas circuits for each; the inner used for oil firing and the outer for exhaust heat-recovery. This avoided problems of exhaust blowback into the oil-fired flue. Another composite form for ships used two boilers: one of minimal form with a central flue, used as a silencer economizer for the diesel engines, and another as a purely oil-fired central flue boiler. The economizer was used with pumped circulation (as it was usually mounted high up) as a feedwater heater. This system was used where a large amount of steam was required even when in port, such as for heated cargoes like banana boats and passenger liners.
The furnace was placed in the space between the tube banks. Early boilers were manually coal fired, later oil fired. The boiler was enclosed in a sealed casing of steel, lined with firebricks. Brick-lined end walls to this casing housed the firedoors or oil burner quarls, but had no heating surface. The uptake flue from the boiler was in the centre top of the casing, the exhaust gases passing around the steam drum. To reduce corrosion from flue gases over the drum, it was sometimes wrapped in a simple deflector shroud. Usually the lower part of the water drums were exposed outside the casing, but only the ends of the steam drum emerged. The water level was at around one-third of the steam drum diameter, enough to cover the ends of the submerged water-tubes.
The weight of the boiler rested on the water drums, and thus on supports from the firing flat's deck. The steam drum was only supported by the watertubes and was allowed to move freely, with thermal expansion. If superheated, the superheater elements were hung from this drum. Compared to the earlier Scotch and locomotive boilers, water-tube boilers with their reduced water volumes were considered lightweight and didn't require extensive supports.
In 1922, Harold Yarrow decided to exploit the increasing boom for electricity generation as a market for Yarrows to build land-based boilers. The first boilers, at Dunston Power Station and Brighton, were of the same marine pattern. As for their naval success, they were recognised for having a large radiant heating area and being quick to raise steam.
Only one "Yarrow" boiler was used in a railway locomotive, Nigel Gresley's experimental Engine 10000 of 1924 for the LNER company. Having observed the benefits of higher pressures and compound engines in marine practice, Gresley was keen to experiment with this approach in a railway locomotive. As with the land-based boilers, Harold Yarrow was keen to expand the market for Yarrow's boiler. 2b1af7f3a8