Rail Burn

A rail burn is a defect in the rail caused by wheel slip - typically a locomotive's driving wheels spinning against the rail instead of rolling. The intense localized heat and friction of the spinning wheel damages the rail surface and leaves a depression burned into the railhead.

How It Happens

A rail burn is created in a single event: a locomotive's wheels lose adhesion and spin against the rail at a standstill or very low speed - most often when starting a heavy train or on slippery rail. With the wheel spinning against one nearly fixed spot, intense heat is concentrated there, and the rapid heating and cooling alters the rail steel and burns a depression into the railhead then and there. Because the damage is to the rail rather than to the equipment passing over it, a rail burn is a track defect, not a car or wheel defect.

Why It Matters

The burn itself is the fixed result of that single slip event - the surface depression does not enlarge on its own the way wear does. What makes a rail burn serious is what can develop from it: the rapid heat-and-quench can leave hardened, embrittled metal and thermal cracks at the spot, and under the continued pounding of wheel loads that damage can become the initiation site for a transverse fracture growing down into the railhead. The FRA tracks this as an engine burn fracture (EBF). So while the burn is a one-time event, the rail must still be inspected and addressed before a fracture grows from it. Rail burns are found and dealt with through track inspection and maintenance-of-way work rather than through car interchange inspection, since the affected asset is the track itself; depending on severity a rail burn is addressed by grinding the railhead or replacing the affected rail.