Victoria & Alexandra -  The Worlds largest working mill steam engines.

Ellenroad Engine House has the only fully working cotton mill engines 

with their original steam plant

The Ellenroad mill engine of 1892 was a triple expansion steam engine built by J&W McNaught of St. George's foundry, Rochdale. When the new ring mill was built, the triple expansion engine was converted to a twin tandem compound engine by removing the high pressure and intermediate pressure cylinders and installing two high pressure cylinders. The conversion was undertaken by Clayton Goodfellow & Co Ltd, Blackburn. the flywheel was increased in size from 43 grooves for 1.5/8" (41mm) ropes to 44 grooves to accept ropes of 1.7/8" (47.6mm) diameter. 58.5 revolutions per minute, the new engine could produce 2650 IHP (indicated horse power).

Steam first enters the smaller, high pressure cylinders being directed into the cylinders through Corliss valves. The rotative valves are operated by Craigs cut-off gear and controlled by the Whitehead governor. The governor adjusts the valve gear continuously to ensure just the right amount of steam is admitted to produce the desired power and speed. The flywheel weighs over 80 tonnes: about the same as nine double deck buses.

The exhaust valves are situated in the bottom of the cylinders and the steam goes through these into the second, or low-pressure cylinders to be used a second time. The low-pressure cylinders have greater diameters than the high pressure cylinders to take advantage of the lower steam pressure. They have piston slide valves. Steam leaves the low pressure cylinders to be drawn, by air pumps into the condensers below the floor.

At the back of the low pressure cylinders there are cross-heads that