Euston approach track layout

[Trog]

I believe that for the 1960's electrification the Up Empty Carriage tunnel (Rat Hole) was enlarged by lowering the tunnel floor and inserting flatter shaped rings in the tunnel sides to give more headroom. The DC tunnels remain their original round shape.

 

[MarkyT]

I believe that for the 1960's electrification the Up Empty Carriage tunnel (Rat Hole) was enlarged by lowering the tunnel floor and inserting flatter shaped rings in the tunnel sides to give more headroom. The DC tunnels remain their original round shape.

The South Hampstead tunnels, the twin tubes for the DC lines parallel to the main line Primrose Hill tunnels, might be rebuilt as necessary for AC clearance and equipped with OHLE by closing them one at a time, whilst diverting services in both directions via the other tunnel. There would be temporary double to single junctions at either end, retaining engineering access from at least one end to the closed tunnel. The 20 minute interval service could be run easily, but times would need tweaking to avoid trains passing in the area.

see

http://www.realtimetrains.co.uk/sea...edule_type=0&show_wtt=1&show_var=1&show_stp=1

A rigid power rail system mounted on the tunnel ceiling, rather than traditional catenary might reduce clearance work required in the tunnels, if it was suitable. I understand these have been used in older Alpine tunnels to increase headroom, but I don't know if there's any precedent in UK or with 25kV.

 

[mr_jrt]

I can't agree with the idea of diverting all the DC lines service away from either the traditional terminus or a new cross London route (e.g. Crossrail).

In respect to freight interaction and future potential HS 1/2/ transfer traffic, I refer you to my idea for diverting NLL and GOBLIN to Kentish Town to avoid significant work at Camden and improve connections. This gives both LO lines a new interchange with the Northern Line and the Thameslink MML arm.

http://www.townend.me/files/kentishtown.pdf

At Stratford a fair proportion of the freight traffic is continuing on down the GEML to Felixstowe. With double headed electrics and maximum speed of 75 MPH, this traffic fits much better on the main (fast) lines, does not have to cross to the reliefs and is thus not affected by Crossrail developments.

Well, when Euston gets worked on, they're removing the short platforms, so sending 4/5 car units to Euston isn't going to be acceptable. Before the cuts the shortest 6 platforms were planned to be 12 cars long, with the other 6 being long enough for 11(14?) car Pendolinos. Even with the cut version, HS2 still plan on removing platforms 9 & 10 to lengthen 5, 6, 8 & 11 to accommodate the long Pendolinos.

There's simply no room at Euston for the DC services, so they'll be going. The cheapest option (thus the most likely) is the Primrose Hill link, so that's what my money's on.

 

[snowball]

A rigid power rail system mounted on the tunnel ceiling, rather than traditional catenary might reduce clearance work required in the tunnels, if it was suitable. I understand these have been used in older Alpine tunnels to increase headroom, but I don't know if there's any precedent in UK or with 25kV.

Not far away on the ground, not far away in this forum, not far away in time.

 

[MarkyT]

Not far away on the ground, not far away in this forum, not far away in time.

Thanks for that. In much more widespread use than I realised, from manufacturer's brochure:

http://www.furrerfrey.ch/web/dms/fur.../EN/SFL_en.pdf

See page 17 (centre) for a photo of a particularly space efficient installation in an old oval profile single track tunnel.

 

[ChiefPlanner]

Putting around half of the present LM service into Crossrail via a new connection solves much of the issues for Euston during the hope for HS2 era.

People go on about the DC into Euston taking up capacity- they don't really as the short 40 mph sprint into Euston from South Hampstead is not much of a capacity - grabber. Admittedly - traffic south of Queens Park on the DC lines is less than north of - always has been...

 

[rebmcr]

People go on about the DC into Euston taking up capacity- they don't really as the short 40 mph sprint into Euston from South Hampstead is not much of a capacity - grabber.

It's not how many paths, it's having those paths on entirely separate metal that's the wasteful bit.

 

[ChiefPlanner]

It's not how many paths, it's having those paths on entirely separate metal that's the wasteful bit.

The DC trains run in on the existing "slow" lines - which are dual electrified - lines B and C , which are shared with LM AC services.

 

[MarkyT]

The DC trains run in on the existing "slow" lines - which are dual electrified - lines B and C , which are shared with LM AC services.

But between Queens Park and Camden all freight to and from the NLL together with all AC suburban trains have to share the slow pair, and negotiate a flat junction at Camden, whilst 2 parallel tracks with completely grade separated junctions at Camden carry the 3 TPH of the DC lines alone.

 

[Trog]

But between Queens Park and Camden all freight to and from the NLL together with all AC suburban trains have to share the slow pair, and negotiate a flat junction at Camden, whilst 2 parallel tracks with completely grade separated junctions at Camden carry the 3 TPH of the DC lines alone.

I doubt moving that flat junction a couple of miles up the line to south of Kilburn High Road would make a difference worth the astronomical cost of the work required to make the DC's fit for AC heavy freight use. Also load limits on the North London Electric lines might be quite severe as they dive down at quite a fast rate. Including an underground reverse curve and short turnouts in Y shaped single bore tunnels.
--- old post above --- --- new post below ---

The South Hampstead tunnels, the twin tubes for the DC lines parallel to the main line Primrose Hill tunnels, might be rebuilt as necessary for AC clearance and equipped with OHLE by closing them one at a time, whilst diverting services in both directions via the other tunnel. There would be temporary double to single junctions at either end, retaining engineering access from at least one end to the closed tunnel. The 20 minute interval service could be run easily, but times would need tweaking to avoid trains passing in the area.

There is no where to put your crossover between the tunnels and the slows at the Euston End, as the Down DC tunnel mouth is literally feet from the Down Slow connection, also the Up DC tunnel mouth is the other side of the slows, further north and at a different level. So your plan would involve WDT running at the Euston End.

 

[class303]

It is, as it's a standard diversionary route for LO NLL services.

How often is it used and by which services please?

 

[Manchester77]

One notable occasion is during the NLL works in 2009 or 2010 where services ran from Stratford through to Watford Junction via Williesden Junction. However it can be used to go Stratford - Richmond via Willesden Junction

 

[MarkyT]

I doubt moving that flat junction a couple of miles up the line to south of Kilburn High Road would make a difference worth the astronomical cost of the work required to make the DC's fit for AC heavy freight use. Also load limits on the North London Electric lines might be quite severe as they dive down at quite a fast rate. Including an underground reverse curve and short turnouts in Y shaped single bore tunnels.

OK understood, but presumably with less work the circular tunnels might be made suitable for AC suburban passenger services only with the freight all remaining on the existing slows. Then the timetable spaces between the Watford stopping services could be used by other suburban trains to overtake freights. New junction arrangements may be needed around Camden for the HS1/2 connection anyway and that is likely to preclude retaining the DC to NLL connection.

The following sketch suggests an idea for creating a grade separated arrangement for freights crossing between the slows and NLL/HS1 connection . . .

http://www.townend.me/files/camdenjn.pdf

Clearly if AC suburban trains other than the Watfords were to use the (former) DC lines, the new junction would still be required around Queens Park, between the slows and DC Lines.
--- old post above --- --- new post below ---

There is no where to put your crossover between the tunnels and the slows at the Euston End, as the Down DC tunnel mouth is literally feet from the Down Slow connection, also the Up DC tunnel mouth is the other side of the slows, further north and at a different level. So your plan would involve WDT running at the Euston End.

I think the job could still be done. For the southernmost (Down) bore closure, displaced Down trains could get to the Up line via an existing crossover nearby without significant wrong direction movement, although additional conflict with the Up Slow is clearly involved and additional signalling routes would need to be provided. For the northern bore closure a new crossover would definitely be required to get displaced Up trains onto the Up Slow as the next existing crossover is almost a mile away. With all the extra Slow line conflicts involved, the temporary timetable adjustments would be rather more complex than I implied originally.

 

[LNW-GW Joint]

There is a proposal to use the DC lines for main-line traffic to allow more/longer engineering possessions between Watford and Euston.
That would trigger a general upgrade of the line.

 

[swt_passenger]

There is a proposal to use the DC lines for main-line traffic to allow more/longer engineering possessions between Watford and Euston.
That would trigger a general upgrade of the line.

Perhaps, but the article about it in Modern Railways reckons during the periods the mainline fast and slows were closed (eg overnight Saturday) they'd just use DC capable LM, LO or even SN EMUs or diesel trains on the Euston - Watford Jn leg, with longer distance VWC services sarting at Watford Jn.

So although they mention beefing up the (DC) power supply for this, it doesn't necessarily need that major an upgrade...

No doubt nearer the time people will expect dragged Pendolinos of course, but that's not necessarily what they'll get...

 

[Nym]

Perhaps, but the article about it in Modern Railways reckons during the periods the mainline fast and slows were closed (eg overnight Saturday) they'd just use DC capable LM, LO or even SN EMUs or diesel trains on the Euston - Watford Jn leg, with longer distance VWC services sarting at Watford Jn.

So although they mention beefing up the (DC) power supply for this, it doesn't necessarily need that major an upgrade...

No doubt nearer the time people will expect dragged Pendolinos of course, but that's not necessarily what they'll get...

Or of course Voyagers...?

Stengthening and better links between the DC and AC lines would be very nice. But running between Queens Park and Stonebridge Park in the evening or during the day at any kind of speed just isn't going to happen, especially with the current signalling, some more intermediate blocks will be needed with more aspects if they want to eek a good amount of capacity out of the steels.

The 45mph linespeed wouldn't be too nice to run with either, perhaps 60/75 would be better, especially North of Harrow & Weldstone. (South of here there is little point with 6tph that struggle beyond 35mph)

 

[Trog]

The 45mph linespeed wouldn't be too nice to run with either, perhaps 60/75 would be better, especially North of Harrow & Weldstone. (South of here there is little point with 6tph that struggle beyond 35mph)

Would only be for 11 3/4MP to 15 3/4MP less speeding up and slowing down, as the DC alignment through Watford is one tight curve after another.

 

[edwin_m]

Kilburn High Road and South Hampstead are close to Kilburn Park and Swiss Cottage Tube stations respectively, so could perhaps be closed down.

Conversion of the DC lines to Bakerloo could help with accessibility as all platforms could then be lowered to Tube height... except Watford High Street which would also be served by S stock via Croxley Link. I think they would still be in gauge for diverted main line stock if this happened, though continued use by diversions would require dual-fitting of two incompatible transmission-based signalling systems.