NRM - collections Frequently Asked Questions. In simple terms, water is heated in the boiler and converted into steam which is fed into cylinders containing pistons. The pistons are pushed backwards and forwards by the expanding steam as it enters the cylinders.
Motion is created by an arrangement of crankshafts and connecting rods acting on the wheels.
Visitors can see the detailed inner workings of a steam engine in the sectioned Merchant Navy Class locomotive Ellerman Lines and in a sectioned replica of Rocket in the Great Hall. Former LNER Class V2 Green Arrow 1936 is in full working order and is occasionally used to haul steam charter trains on Britain's mainlines. For a steam locomotive to run on the mainline in Britain it needs a full mechanical overhaul, boiler insurance, a spark arrestor test, and ultrasonic testing of wheels, all of which are very costly. For example, Flying Scotsman has recently cost in the region of 750,000 to restore to mainline condition. Boiler certificates last ten years and are valid for seven years on the mainline.