Scheffel bogie
A Scheffel bogie is a flexible, high-stability bogie designed to reduce lateral force vibrations and accommodate turning on narrow gauge tracks at high speed. It first went into service in a fleet of South African Railway (SAR) ore wagons in 1975. It is named after its inventor, Dr. Herbert Scheffel, who designed the Scheffel bogie to facilitate the development of South Africa's  narrow-gauge railway system. The Scheffel bogie was used to set the world narrow gauge speed record of  on Cape gauge tracks.