N7 Tank engine of Alfred John Hill at Cheddleton

The GER Class L77, LNER Class N7, is a class of 0-6-2T steam locomotives. They were designed by Alfred John Hill of the Great Eastern Railway and introduced in 1915. The design was perpetuated by Nigel Gresley of the LNER after the 1923 grouping. 134 were built; only one of them is preserved.

 

 

Also at Cheddleton on the Churnet Valley Railway

 

The N7s had superheaters and piston valves. They were unusual (for inside-cylinder locomotives) in having Walschaerts valve gear. They were, as London suburban locomotives, fitted with Westinghouse air brakes.
Some were fitted with condensing apparatus for working on the Metropolitan Line and the East London Line but the condensing apparatus was removed between 1935 and 1938.

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