Class 423F 4-8-4T (1954)

Class 423F 2-Cylinder General Purpose Tank Locomotive
Designed by Mikhail Rodnivacek
Built in 1954 by Friedrich Krupp, Essen, Germany

The 423E was in every way the tank version of the 423E, the drawings of which were extended to include the rear bunker and trailing bogie (which is identical to the leading one), plus the side tanks. With their good acceleration and turn of speed, these husky engines were the absolute masters of the Bevice and Kropčahne suburban services, which at peak hours maintain a headway of as little as seven minutes. A further contingent of 423Fs was allocated to branch lines in the south, where their 1560mm wheels stood them in good stead on the sometimes stiff gradients and being tank engines enabled them to run to termini where turntables are too small or non-existent. Krupp, of Essen, supplied a total of 110 locomotives over a period of three years, making this one of the last large steam orders supplied by a German firm to a customer within Europe. The changeover to poppet valves on the RSR was proceeding apace when these locomotives were delivered and came just too late for the order to Krupp to be amended. Starting in 1956, all engines were converted at the first opportunity (usually in connection with the first general overhaul), becoming class 423FF.

Class 423FF 4-8-4T (1956)

In the mid-1980s, the remaining 83 members of the class were rebuilt to class 434F.

Text and graphics © Norman Clubb 2015