A History of the South African Railways 25 Class Condensers and 25NC 4-8-4’s. After the Second World War, the South African Railways were in dire need of more motive power for its growing traffic, particularly for the artery connecting the Johannesburg area with Cape Town. This includes the 340 mile crossing of the semi-desert Karoo, where water is scarce. Comprehensive studies and development work led to the order for 90 Class 25 4-8-4s with condensing tenders and 50 non-condensing locomotives, Class 25NC, from North British and Henschel. They were the largest non-articulated narrow gauge locomotives ever built and the largest locomotives to use the Henschel condensing system.
In this book, renowned steam engineer Phil Girdlestone details the development of these ultimately very successful locomotives, which incorporated much American technology, such as cast steel frames, automatic axlebox wedges and firebox circulator tubes. He explains the many efforts to improve mechanical and thermal efficiency and output, and the initial problems with the separation of oil from the condensed steam, blower fans, the roller bearing rods and breaking connecting rods.
The locomotives were delivered in 1953-55. Their low water consumption and excellent riding qualities earned them their nicknames. Twenty years later, the usefulness of the complicated condensing locomotives was over, and by 1980 all but three had been converted to non-condensing. Regular service ended in 1992, but no less than 31 have been preserved. The book is illustrated with several technical drawings and numerous colour photographs showing these impressive machines at work in the often stunning South African landscape. In all, the book is a worthy tribute to SAR’s most remarkable locomotives. 160 pages A4, hb.