Report on derailment near Trofors station, Nordlandsbanen line

The train continued for approximately 1,000 metres after the derailment. The derailed wagons suffered damage to their wheels and brake suspension, and some brake blocks were missing. There was damage to rails, sleepers and fastenings on a section between the 366.1 and 365.0 kilometre points in the direction of Trondheim.

Welding work had been carried out at the derailment site in October 2013 without the track being neutralised. This resulted in high compressive stresses on the track during a prolonged hot spell in the area in May 2014. A decision had been made to carry out neutralisation in spring 2014, but the work had not been registered in BaneData as deferred corrective maintenance. In this case, the work had been forgotten as an outstanding job. In connection with the derailment, minor adjustments to the track had also been carried out earlier the same day. The Accident Investigation Board Norway (AIBN) believes that this may have weakened the lateral stability and resistance to buckling of the track, which was already subject to compressive stresses.

The Head of the National Rail Administration's Region North has informed us that the rules have been tightened and that the welding of rails is no longer carried out unless the track can be satisfactorily neutralised at the same time, or fishplates are used if rails have to be replaced in temperatures that lie outside the neutral temperature range.

The AIBN does not propose any safety recommendations in connection with this investigation.