Rail sprinkler train- sansui ressha

[bikkuri bahn]

Perhaps a unique to Hokkaido operation, running of sprinkler trains when the ambient temperature rises above 32 degrees C in summer (rare), to cool the rails.  This operation was ended this year, due to modifications in rail maintenance that allow rails to heat up to 57C (up from the previous 52C) without fear of distortion. Scene on the Hakodate Main Line in the suburbs of Sapporo (Atsubetsu Ward), two years ago.

 

Edited August 28, 2014 by bikkuri bahn

[miyakoji]

Was this really effective? I suppose the answer is yes, but I'd expect that water to evaporate in 20 minutes, and the rails to be too hot again in 90.

[katoftw]

concrete ties and normal rails should be good for ballast/ground temp to hit 59C before buckling will occur.  So 57C is the normal safe limit before action may be taken.  I know my home rail operation has sensors in the ballast, and since it get very hot in summer, they go bezerk in summer.  Lots of speed restrictions in summer time in sections of track.

[westfalen]

concrete ties and normal rails should be good for ballast/ground temp to hit 59C before buckling will occur.  So 57C is the normal safe limit before action may be taken.  I know my home rail operation has sensors in the ballast, and since it get very hot in summer, they go bezerk in summer.  Lots of speed restrictions in summer time in sections of track.

When the temprature reaches 32C here we're still wondering when summer is going to arrive. :) We had restrictions of 60kph from Ipswich to Corinda and 80kph from there to Roma St one day last summer but we still ran on time because of all the slack in the timetable.  I pitied the poor coal train crews though, they were restricted to 40kph all the way from Rosewood to Toowoomba.

 

I wonder if runnning the sprinkler trains allowed JR Hokkaido to dispense with speed restrictions.

Edited August 29, 2014 by westfalen

[Davo Dentetsu]

I noted the DD51s looked like plough units without the ploughs...

[katoftw]

I noted the DD51s looked like plough units without the ploughs...

DE15s.

[bikkuri bahn]

Was this really effective? I suppose the answer is yes, but I'd expect that water to evaporate in 20 minutes, and the rails to be too hot again in 90.

Yeah, cooling the rails was only effective for 90 minutes, likely one reason why the process was ended and a different approach used.  The summers are getting hotter here, and starting earlier in the year.

[bikkuri bahn]

I wonder if runnning the sprinkler trains allowed JR Hokkaido to dispense with speed restrictions.

 

Perhaps, this train was used particularly on the curvy sections of lines approaching the Sapporo metro area- impact of speed restrictions would be telling on the suburban and intercity traffic if they intruded on the peak hours.

[Davo Dentetsu]

DE15s.

Erm... those, even