Crossrail/Elizabeth Line. From construction to operation - ongoing discussion

[whole diary]

[SandTEngineer]

Details of the rebuilding of Acton Main Line station.  Perhaps it should now be renamed Acton Elizabeth Line?   

http://www.crossrail.co.uk/news/articles/green-light-for-major-improvements-at-acton-main-line-station

Hope the new platforms are not going to be 200m long as the new trains are 205m long

[onthecushions]

Elswhere on the LizRail website it says that platforms are to be 250m long.

Just nice for standard formations of 12 x 20m or 10 x 23m.

Pity the young journalists writing up these articles can't quote figures accurately.

OTC

[Electric train]

There will be some platforms with SDO^▸ (Selective Door Opening), Hanwell and Twyford (Plat 4, not sure about the other 3) are 2 examples I know of

[IndustryInsider]

I think you can add Langley, Burnham and Taplow to that list.  That was certainly the case originally anyway.

[stuving]

Hope the new platforms are not going to be 200m long as the new trains are 205m long

That's a bit mean.

The press release actually says: "Platform extensions to accommodate the new 200 metre long trains."

I'd say that's truly approximate - in the original sense of "close enough for our current purposes" (i.e. a non-technical journalism/PR^▸ (Public Relations)).

But how long are these trains? There's no real technical data that I can see.

Wikipedia doesn't know (unusually). Bombardier would rather not talk about Aventra at all. And Bomdardier do say "Each Crossrail train will be just over 200 metres in length, made up of nine carriages and able to carry over 1,500 passengers."

They were specified as 205 m long or less, and to carry 1500 or more. The tunnel platforms are 250 m long, and the ITT^▸ (Invitation to Tender) called for one or two extra vehicles per unit within that length. But Crossrail refer to this full length as 240 m. And those are all published figures - the ITT may have been slightly different.

Now if 11-car is 250 m, then 9-car is 204.5 m - which I think I've seen quoted. But I suspect it's closer to 245 and 200.5 m.

Not that the odd metre or two within the predefined limits makes a whole load of difference.

[SandTEngineer]

All I can tell you is that the specification for the part of the Elizabeth Line that I'm currently working on specifies 205m with the option to make passive provision for 240m.  There is a +/-1m stopping tolerance that has also been specified.  Hope the new drivers are good at braking............

[IndustryInsider]

Article on the Acton Dive Under - now pretty much complete with work to install electrification equipment currently ongoing:

https://www.ianvisits.co.uk/blog/2016/07/24/crossrail-completes-acton-railway-dive-under/

[Electric train]

Article on the Acton Dive Under - now pretty much complete with work to install electrification equipment currently ongoing:

https://www.ianvisits.co.uk/blog/2016/07/24/crossrail-completes-acton-railway-dive-under/

Looking at the type of OLE^▸ (Overhead Line Equipment, more often "OHLE") fittings they are putting up looks like its going to use conductor beam

[onthecushions]

I was wondering whether there is any scope for the conductor beam in place of catenary on surface track? The problems of tension, weight and sideways thrust would be avoided.

OTC

[paul7575]

Yes.   It can be used in theory, but it needs a massively increased number of portals to hold what is now a heavier and rigid conductor system in place.   So its only practical use on plain track is probably to deal with relatively short sections between tunnels that actually need it.

There are pictures of conductor beam in use in the open on Furrer and Frey's website.

http://www.furrerfrey.ch/en/systems/conductor_rail.html#

Paul

[onthecushions]

The "in the open" masts looked quite slim and the temporary installation used existing spacing masts. It was also claimed to be "elegant" and even could be "hinged" !

I agree that they were trying to sell it but the case for it appears stronger.


OTC

[Electric train]

Article on the Acton Dive Under - now pretty much complete with work to install electrification equipment currently ongoing:

https://www.ianvisits.co.uk/blog/2016/07/24/crossrail-completes-acton-railway-dive-under/

Looking at the type of OLE^▸ (Overhead Line Equipment, more often "OHLE") fittings they are putting up looks like its going to use conductor beam

I have the (mis) fortune to pass the dive under at a speed I could see the OLE fittings.  On a "closer" inspection they are in fact standard contact wire and catenary arrangement.

Conductor beam needs a support at a max of 12 metres (for a 110mm beam) closer together for high speed,

[stuving]

Conductor beam needs a support at a max of 12 metres (for a 110mm beam) closer together for high speed,

For comparison, conductor wire is supported at 70 m max intervals (F+F figure).

[onthecushions]

MR^▸ (Midland Railway) August gave a spacing of 8.5m for the roof supports in the Severn Tunnel. It depends how "floppy" the beam is and the necessary curvature.

There's also a new  acronymn on the block - ROCS^▸ (Rigid Overhead Conductor System) - Rigid Overhead Conductor Systems! F & F describe them as "fit and forget", with favourable whole life costs.

I believe the outdoor GW^▸ (Great Western) masts/stanchions are spaced at 50m compared to Mark 3 at 73m max.

OTC

[Chris from Nailsea]

There's also a new  acronymn on the block - ROCS^▸ (Rigid Overhead Conductor System) - Rigid Overhead Conductor Systems

Thanks, onthecushions: I've added it to the Coffee Shop forum acronyms / abbreviations page. CfN.