Reed water tube boiler

Advantages of the water tube boiler included comparative lightness and the ability to run at higher pressures.

[5] However, it was a vertically integrated business: from about 1857 it possessed its own source of iron ore, mined near the North Yorkshire coast in the vicinity of Whitby and Saltburn, and, according to the local historians Jim Cuthbert and Ken Smith, "it was said that [Palmers' shipyard] brought in iron ore at one end ... and sent it away again at the other end in the form of finished ships.

[13] In the Reed boiler, the tubes were bent into pronounced curves of varying radii to maximise surface area and therefore steam production, and baffles were used to direct hot gases.

[20][21] The down-comers thus promoted convection within the boiler, which needed to be rapid because of the small diameter of the tubes, and formed "a substantial part of [its] framework.

"[19][22][17] Steam was collected inside a dome on top of the top chamber, from which it passed out of the boiler for use via engine room controls, and in the Reed boiler all but the dome and the ends of the three water chambers was enclosed in a double-layered casing with an air gap and asbestos lining that reduced the temperature of the outer layer.

[17][25][26] A constant supply of pure water was essential for this type of boiler, as a shortage of water would rapidly result in an empty boiler liable to severe damage from the furnace, and the deposition of any contaminant, such as limescale, would result in a significant loss of efficiency and could block tubes.

[31] Therefore, additional feedwater was required, and it was supplied by apparatus such as an evaporator, as was fitted in HMS Spiteful, built by Palmers and launched in 1899.

[42][43] As fitted to torpedo boat destroyer HMS Lightning in 1895, a dry Reed boiler weighed 13.25 tons (12.44 tonnes).

[17] A Reed boiler could be designed to operate at internal pressures of up to 300 pounds per square inch (2,068 kilopascals) and, as constructed for torpedo boat destroyers such as Spiteful, which was capable of steaming at 30 knots, a set of four boilers and associated machinery required nearly 25 miles (40 kilometres) of tubing.

[51] Reed boilers were also installed in ships ordered by the Admiralty from other shipbuilders, for example on the River Clyde in Scotland.