A Practical Manual On Sea Water Distillation
With A Description Of The Necessary Machinery For The Process

SPARE GEAR. 155 of ample size to compensate for the furring up which in- evitably occurs. Steel pipes are now sometimes used. 19. The pipes through which the drinking water passes should be tinned inside. (d) Spare Gear. 20. Spare gear may be divided into two lots—First, such articles as are required to work the apparatus in the ordinary way—e.g., spanners, interchangeable coils (for convenience when the dirty tubes are being cleaned). &c.; and secondly, such articles as may be considered requisite to replace parts that are subject to much use and wear—e.g., the moving parts of the pump, &c. 21. On Government ships the spare gear is somewhat considerable, as will be seen from the list, which is sub- stantially as follows :— For the Pump.—Practically all the moving parts are duplicated in the spare gear, and these have to be fitted in place and worked when viewed by the inspecting officer, who generally also inspects the original moving parts under working conditions. For the Evaporator.—A complete set of heating surfaces is required ready for replacing the set already in the evaporator. All the coils and the separate parts of coils must be interchangeable. A spare coil drain is also some- times specified. For the Distilling Condenser.—The spare gear includes a set of cooling surfaces. The surfaces are usually fitted in gun-metal plates, so that the whole sheaf of tubes may replace the sheaf already in the distiller. Sometimes, however, the whole sheaf is not required, but simply a spare set of loose tubes.