Safety Assessment for Flange Climb Derailment of Trains Running at Low Speeds on Sharp Curves

This paper investigates the possible causes of flange climb derailment in trains running at low speeds over sharp curves. Typically the load of the high rail decreases due to the over-canting and track twist after the initial section of a transition curve during the following sharp curve. Researchers used both test track field data, along with laboratory work using bench tests, which analyzed creep force using roller rigs. They discovered an estimated Y/Q ration (with Q being wheel load and Y being lateral force) that may assure drivers that low speed rail vehicles will not derail even in conditions when it would otherwise occur (as well as in the absence of anti-derailing guards). The authors also suggest a safety assessment protocol using the offloading of ∆Q/Q0 ratio in the same circumstance.