DF200 derailment in Hokkaido

[yakumo381]

Loose bolt causing a DF200 derailment. Another JR Hokkaido maintenance problem?

 

https://www.youtube.com/watch?v=kmGePJGG8rg

 

[Jace]

Loose bolt causing a DF200 derailment. Another JR Hokkaido maintenance problem?

 

 

In a way, maybe, but also a design issue. Not sure what fell (Doppler radar?) or the weight but, going by the graphics in the clip, not a good idea to have a part suspended from the truck and held in place only by bolts in tension. Lots of vibration down there; fastener grade and design, torqueing and locking mechanisms are all important details. Sometimes these details get lost in the shop, they can get pretty esoteric - lots of discussion here about wet versus dry torque values on various truck bolts, or sometimes the wrong nuts, bolts or washers are grabbed from the bin. Until that gets sorted out, break out the ty-wraps!

[HantuBlauLOL]

if the problem is on the bogie, isn't it JRF's fault?

[Densha]

On the same day a train from Kumamoto Dentetsu also derailed: https://twitter.com/matunonnn2669/status/834659021604872194

 

This already quickly led to Japanese Twitter users pointing out the derailing of two 'bears' on the same day.

[miyakoji]

wet versus dry torque values

Wet with water, lubricant, other?  I had never thought of tightening fasteners under other conditions.  Certainly seems like a fine detail that could be overlooked.

 

if the problem is on the bogie, isn't it JRF's fault?

 

It would seem so, unless JRH is doing some maintenance for JRF.

[yakumo381]

On the same day a train from Kumamoto Dentetsu also derailed: https://twitter.com/matunonnn2669/status/834659021604872194

 

This already quickly led to Japanese Twitter users pointing out the derailing of two 'bears' on the same day.

 

May be the camera angle or foreshortening but looks very close to those household gas cylinders, could have been an explosion if had been hit...

[Nick_Burman]

This already quickly led to Japanese Twitter users pointing out the derailing of two 'bears' on the same day.

 

Two operators bearly coping with daily problems...

 

Groan...

 

Cheers NB

[kvp]

For me it looks like one of the screws holding the bogie pin fell out then the whole assembly fell down to the tracks. It either broke or they are using a very short one for the job and a lack of a through hole safety wire is also strange. (it's only required on aircraft though) This might be a design or maintenance issue, but a rather small one.

 

On the other hand, those gas flasks are really close to the tracks, i wonder if it's even allowed to put them there. If the derailment happened about a meter closer, then they would have been hit and pulled under the train.