High Catenary for Double Stack Trains in India

[jis]

India has chosen to operate their double stack trains on standard flat cars rather than well wagons as in the US. Consequently they stand 21' tall. To allow for sufficient safety margin and such, India has standardized on 7.5m (24.6') catenary height for routes where these double stacks will be allowed to operate. Standard Indian catenary is 6m (19.7') above rail top.

Here is a video which shows and express passenger train operated by an electric loco (WAP-6 Class 6600HP 25kV 50Hz AC drive) equipped with a high catenary pantograph. Looks a bit weird but apparently there is no problem operating at upto 100mph, though this one is operating at about 70mph.

This video is primarily about the last diesel run and the first electric run of an intercity higher speed day train between New Delhi and Ajmer (in the state of Rajasthan, southwest of New Delhi) The high catenary loco sequence begins at about 1:01



And another one of the same train at an open main line location

 

[Dutchrailnut]

to do that, they did not have as many viaducts to be raised as we would need to do here , clearances prevent us to have catenary even at a steady lower height in USA specially on east coast .

 

[jis]

to do that, they did not have as many viaducts to be raised as we would need to do here , clearances prevent us to have catenary even at a steady lower height in USA specially on east coast .

Except for about 150km of existing trackage, all the high catenary trackage is new construction as part of the so called DFC (Dedicated Freight Corridor) project which is being built to connect the so called Golden Quadrilateral (the corners being Delhi, Mumbai, Chennai and Kolkata, or actually their distant suburbs where land ports provide transfer to road or standard height trains) all across the country. So any viaducts involved are also new constructions. The project also includes connections to a few large container transshipment ports, again all new constructions.

The video in my earlier post are all on one of the upgraded existing portions. What is interesting is that this RoW was originally built for Meter Gauge built by Rajputana and Malwa State Railway, and was only very recently converted to Broad Gauge. In the process of conversion they had to deal with the viaduct issues and possibly rebuilt them with space for high catenary.

The section between Delhi Cantonment and Rewari shown in the first video was part of my old stomping ground during my grade school and high school days.

 

[west point]

The high CAT requires one item of track. The cross levels between the 2 rails need to be level so the pan does not wobble too much side to side. a one inch deviation of rails would translate to what at 24 feet? A 1/12th inch would equal

 

[cirdan]

I wonder why they opted for normal height flatcars rather than well cars. Does the broader gauge add stability to any significant degree? Are operations halted in case of strong winds?

Also the tall pantographs intrigue me. On the streetcar system in Blackpool, England the overhead has clearance for double decker cars and many of the single deckers have standard issue pantographs but put they them on top of a tall perch or tower so they reach the catenary. I wonder if IR ever considered that? Maybe its less practical for maintenance access. It would also require some mechanism to retract the perch when operating on normal lines. I wonder if the very large pantorgraph has any aerodynamic issues? I think it was SNCF who did research into that and found air turbulence would sometimes lead to loss of contact.

 

[PeeweeTM]

I'd guess one advantage of normal cars is car length to cargo length rate. With bogies under the cargo, you only loose length with buffers/couplers.
Every container you can put extra in a siding/train is money.

And having the containers closer to each other reduces drag a bit.

 

[jis]

I'd guess one advantage of normal cars is car length to cargo length rate. With bogies under the cargo, you only loose length with buffers/couplers.
Every container you can put extra in a siding/train is money.

And having the containers closer to each other reduces drag a bit.

Both of those were the reasons given by Indian Railways RDSO (Research, Design and Standards Organization) for the choices they made. The matter was studied extensively over 5+ years before deciding on a standard.

In effect it just adds 1 more foot to the height over the US Plate H.

The container carriers all have CBC (AAR) (CBC = Center Buffer Coupler) and are air braked. India still has some remaining Buffer-Chain coupler stock and also vacuum braked stock. But nothing new comes with those, except some locomotives which come with dual brake and transition coupler systems that can operate universally.