New rolling stock for Sapporo City Subway Toho Line

[bikkuri bahn]

Sapporo City Transportation Bureau announced Oct. 31 that new rolling stock for the Toho Line, designated the 9000 series, will begin operation next year in April.  The new sets will begin to be delivered to the Toho Line depot next month from KHI Hyogo.  A total of 80 cars, arranged in 4 car sets of 20, will be delivered by FY2016.

 

The new units will be fitted for ATO/DOO, in conjunction with platform door installation on the Toho Line.  They will be equipped with VVVF inverters and interior LED lighting.  Bogies and portions of the couplers from current Toho Line stock will be reused on the new units to reduce costs.  In addition to emergency escape ladders fitted on the cab car ends, ladders will also be fitted to the middle cars.  Interior fittings will employ "universal design" principles to create a barrier free passenger experience.

 

 

http://response.jp/article/2014/11/04/236554.html

http://news.mynavi.jp/news/2014/11/04/426/

Edited November 7, 2014 by bikkuri bahn

[Densha]

I didn't know they had a metro system in Japan with rubber tyres. I once rode a metro line in Paris with that system and the ride characteristics were awful.

[bikkuri bahn]

It's certainly not as smooth as a steel rail system, but it's OK, especially the later built lines that use a steel guideway rather than the original concrete.

[kvp]

Those are different systems. The paris metro left the original steel rails in place and added steel guideways for the rubber wheels next to them. The sapporo system uses a raised middle guide rail and doesn't have the steel rail fallback system. Imho, both systems are bumpy and way too complex compared to a good steel rail system. A similar, but imho nicer system (with side guide walls) is the one used by the automated trains of the Yurikamome in Tokyo.

[Densha]

I don't really get what the advantage is of these systems compared to a normal railway. What to do when you have a flat tire for example? "Due to a flat tire the train will not run today."

[railsquid]

That's why they carry a spare tyre and a hydraulic jack .

[bikkuri bahn]

I have never experienced (or heard) of a failure with the wheel system the 14+ years I have lived here (I ride the subway 7 days a week)- the occasional signal problem yes, but never anything to do with the rolling stock proper.

[kvp]

 

I don't really get what the advantage is of these systems compared to a normal railway. What to do when you have a flat tire for example?

Advantages:

-can be more quiet

-can run on more steeper gradients

-can run on cheap concrete guideways

-can run in case of snowy and icy weather

 

The flat tire problem:

-Paris metro: they left the steel wheels in place, held off the steel rails by tire pressure, in case of a flat, the train runs on the steel backup wheels

-Sapporo metro: they have double wheels, which are bad at cornering, but means a 100% redundancy

-Tokyo Yurikamome: they have run flat wheels, which means there is a slightly smaller solid rubber wheel inside the pneumatic one

 

The Paris metro solution is a refit for existing lines and combines the problems of both systems without much benefit. The Sapporo system is better, but the center guide rail and the double wheel bogies makes it too complex, the turnouts error prone and the whole system rather expensive. The Tokyo Yurikamome system is a cheap alternative that has only one disadvantage, because of its limited top speed and car length, its capacity is only comparable to light rail, instead of a heavy metro system. But since it's meant to be a tram replacement, this is acceptable. For heavy rail usage, imho the steel wheels on steel tracks solution is better in almost every aspect.

[bikkuri bahn]

The trains on the Tozai and Toho line do not use double wheels, they are single.

 

There is no unified explanation for adoption by Sapporo City of the rubber tyre system.  However, the railway culture then present in Sapporo in the late 60's/early 70's may have a bearing- the railway system (JNR) at that time was still very much a steam era railway- electrification on one line only had recently been completed.  Passenger traffic was very much focused on long distance services (and heavy coal traffic), there was very little commuter traffic then as Sapporo was still a relatively small metropolis then, with suburban development just beginning.  Is is telling that the emu introduced on the electrified segments was the 711 series- an express type with only two narrow doors per side, and slow acceleration.  To people back then, when they talked about "densha", they meant the tram system.  The subway was originally intended to replace the tram system, and station stop spacing was planned more or less equivalent to the above ground tram stops.  Thus the high acceleration of rubber tyre stock was deemed advantageous.  Also, there were steep grades on segments of the planned subway line (40 permils), so rubber tyre had an advantage over steel wheel/steel rail.  No doubt Kawasaki Heavy made a heavy sales push, and now benefit from vendor lock.