South African Class 15F 4-8-2

The South African Railways Class 15F 4-8-2 of 1938 was the most numerous steam locomotive class in South African Railways service, with 255 Mountain type engines entering service between 1938 and 1948. Designed under W.A.J. Day, the Chief Mechanical Engineer, as a development of the Class 15E, it used Walschaerts valve gear rather than rotary cam poppet valves. The engines were built in five batches by four makers in Germany and the United Kingdom: Berliner Maschinenbau and Henschel in 1938, the North British Locomotive Company of Glasgow for 204 of them in three batches between 1938 and 1947, and Beyer, Peacock and Company in 1944. Several later took the large twelve-wheel tenders of the withdrawn Class 23.