C4/​1996R A Freight Wagon Falling Down from the Rail­way Bed on Bridge at Hyvinkää, on 14 May, 1996

27.10.1997

On Tuesday, 14 May 1996 a loaded freight train was being shunted from the Hyvinkää workshop towards the Hyvinkää station along a branch line. The train was proceeding at an acceptable speed towards the bridge that leads over Kerkkolankatu Street. This street was heavily trafficed. Just before the bridge the seventh wagon of eight in the train derailed, traversed the entire bridge and, after the bridge, fell down from the high railway bed. An empty intermediary wagon that was behind the fallen wagon also derailed.

The glass carried in the car was destroyed, and the track was damaged along a stretch of about one hundred metres. No-one was injured in the accident. The total damages from the accident were less than 100 000 USD.

There were four principal reasons for the accident:

At the point where the car derailed, the track changes from flexible to rigid. K-43 rails, fastened with springs and screws to wooden cross-ties, change to K54-rails permanently fastened to concrete structure. At the same time, the rail gauge narrows by almost 9 mm for a short stretch.

The track curves to the left, and particular the light rail had become worn.

The train braked, and so the trailing wagons were subjected to a side thrust going towards the light.

The bogie centre of the fully-loaded Russian wagon that derailed was rough and lacked oil. This resisted the turn of the bogie, and in this was contributed to the derailing.

Recommendetion S58
Recommendation S59