South African Class 10B 4-6-2

The South African Railways Class 10B of 1910 was a class of 4-6-2 Pacific type steam passenger locomotives from the pre-Union era in the Transvaal. Ten locomotives, designed by Central South African Railways Chief Mechanical Engineer G.G. Elliot on the Class 10 design of his predecessor P.A. Hyde, were ordered from the North British Locomotive Company and delivered in 1910 as Class 10-2, five using saturated steam and five superheated with Schmidt superheaters. When they were assimilated into the South African Railways in 1912, the five superheated engines became Class 10B and the saturated ones Class 10A. Five more superheated Class 10B locomotives, built by Beyer, Peacock and Company, were delivered in January 1912, so the class was built by two firms. They had plate frames, Belpaire fireboxes, Walschaerts valve gear and 62 inch coupled wheels, the largest yet used in South Africa, and the superheated engines could handle almost 25 percent more load than their saturated sisters. They hauled passenger trains out of Johannesburg, spent most of their lives on the Cape Midland system out of Port Elizabeth, and were scrapped in 1974, although three of the reboilered Class 10BR survived into preservation.