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What does double stacked mean. Thanks.

One container stacked above the other. Like this:


Source: Google Images

Had snapped this sometime back. :)

Which are the other countries? What gauge do they use?
What is the distance of the top of the upper container from the rail?

Sutripta

Going by the numbers mentioned, this seem to have significant savings. With minimal investment on infrastructure, they can quickly add container loading/unloading equipment at multiple stations to make this easier.

I'm just curious about the feasibility of deploying this on the network. Two major disadvantages I can think of immediately:
- since a lot of rail routes are getting electrified, would the height of the current electric lines be able to clear the height of two containers
- this obviously can't be deployed on any route with even a single tunnel, over-pass, under-pass: must be a huge limitation?

In the case of electrified sections, won't the tops of double stacked containers be fairly close to the OHE (even with heightened OHE installation), thereby leading to increased electric losses to ground?

Also, when hauled by electric locomotives, doesn't the pantograph have to be raised unrealistically high?

The OHE is higher than the normal ones so they clear the double stack.
I think they have identified routes were this is feasible and on which container traffic is high and hence makes sense.

Double stack containers rakes have been running on IR for a while now, except they were on non-electrified routes.

The picture in post 900 shows the taller panto. The loco is retro-fitted with one normal panto and one taller one for the double stack sections.

The video below shows the same train in action;

https://www.youtube.com/watch?v=3c7BcYX9ORc&t=0s

@tharian, thx, I've seen such videos. I estimate the tops of the double stacked containers to be within 20 inches of the OHE, and could lead to increased electric losses to ground.

Besides, such a tall panto may be a hindrance to high speeds.

In which case perhaps leaving then un-electrified would have been better.

Hence the doubt.

Do the tracks have the raised OHE permanently? Does this mean even regular passenger trains also need locos with longer reach pantographs? Or is this done only on the freight corridors?

Perhaps IR has done something about electric losses.
Freight anyway has a low permissible speed compared to passengers.

This whole electrification is in fast forward mode and everything in sight is getting electrified including diesel locos!

It is mainly on freight corridors.

If you look at the following YouTube video, you'll see that few locos have been fitted with both the pantos and they're used as per the need of section. Even passenger trains are being run on high rise panto section.

High rise pantograph

What is the mechanism for this loss?

Sutripta

Capacitive losses, air being the dielectric. There is always a capacitance bween 2 conductors. The OHE carrying AC will dissipate capacitively thru the top of the metallic containers to ground, esp more so if the tops are close to the OHE.

At 25KV, a few inches separation causes heavy sparking. 20 inches may not cause sparking but may be enough to cause losses. An IR electrical engr could confirm better the extent of losses.

What is the frequency? What sort of cable is used? ACSR?

Sutripta

Dunno. Which is why I was hoping an IR electrical engr could shed more light.

Here, I am trying to answer multiple people. The current double-stacked container routes are envisaged for the western dedicated freight corridor which is being built, and the routes from Pipavav and Mundra Ports, which are being doubled and electrified. The routes from the ports in Gujarat, head to Delhi via Viramgam, Palanpur, Abu Road, Marwar Junction, Ajmer, Jaipur and then to Delhi. The long term intention is to have double-stacked container trains, being hauled by electric traction on the routes with heavy container traffic originating from JNPT, Kandla, Pipavav, and Mundra. Currently, the route from JNPT to the north goes via the congested Mumbai-Delhi route via Baroda, Ratlam, Kota, and Mathura, whereas the trains from Gujarat go via the partly doubled Ahmedabad-Delhi route. The WDFC will greatly reduce congestion on these routes. The routes from the Gujarat ports will merge with the WDFC at Palanpur and Ahmedabad, hence WR has doubled and electrified the routed mentioned in the press release with high mast categories. This is to allow a seamless transition from the western railway to WDFC. Indian Railways has the highest height of catenaries globally reaching a height of 7.57 meters, as we don't have the type of low well cars operated by American train companies. This high height will allow us to carry two full-size 40-foot containers, with our rolling stock. Americans double stack their trains to a height of 6.5 meters.

With the high reach pantograph (model is WBL-85HR), being retrofitted to many locomotives, it appears majority of IR's rolling stock will be compatible with both normal routes as well as high rise routes. As many of you know, India is pushing for 100% electrification of all railway routes, hence we have to go for the usage of high rise catenaries for double-stacked operations, instead of the primarily diesel hauled freight operations of nations like USA, Australia, Kenya, Saudi Arabia, and Panama. The status of China is not very well known to me. All these nations use standard gauge. The Dutch too are attempting double stacked operations.

The double-stacked trains have a max speed limit of 110 mph, which is decent for freight operations. Also, the ancillary railway infrastructure of the WDFC is being built in accordance with the height of the double-stacked trains planned to run on it.

I hope this answers all questions.