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Great Western Electrification Progress

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jimm

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The trouble is across the Vale, NIMBYS have fought day after day to stop new housing developments.

With new developments comes new and improved road infrastructure. So start saying "Yes" to new schools, health centres, shops, roads & homes and there will be alternative routes.

First thing to build should be the A34M running from Swindon past Didcot and across to Aylesbury and Milton Keynes. It would open up vast swathes of the countryside and improve the lives of millions.

Sorry, but we are where we are and in the case of the rather large Grove airfield developments, the nimbys have not done very well at stopping anything. Not that development here was ever going to pay for any new bridges for either the A338 at Wantage Road, or the A417 further west, anyway, never mind extra roads.

The A34 doesn't go anywhere near Swindon, nor would any A34M. And even if some new road had been built from Oxford to Swindon, it would be running north of the railway, so would do nothing to assist matters crossing from the Wantage area anyway, so the bridges where Network Rail has fouled up would still need rebuilding.

And why you are quite so enthusiastic about some new road and concreting over a huge swathe of the Vale beats me. It would be the end of any prospect of reviving an Oxford-Didcot-Swindon-wherever train service and only add to the traffic congestion in Oxford and Swindon, so where's the benefit in that?

Yes, and such is an example of gold plating in the extreme.

From the number of times people moan about it you would think that the ECML was non functional because the headspans fall over every five seconds or something.

I am not convinced the business case for abandoning them really makes that much sense. Especially with the balooning cost of electrification.

I think you'll find any cost increases on the GW route have rather more to do with the muddle over bridge replacements than with the overhead kit.
 
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FOH

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Yes, and such is an example of gold plating in the extreme.

From the number of times people moan about it you would think that the ECML was non functional because the headspans fall over every five seconds or something.

I am not convinced the business case for abandoning them really makes that much sense. Especially with the balooning cost of electrification.

I thought the case was more about flexibility than reliability. When on a four track railway and working on the lines, headspans require all power shutoff whereas gantries would allow two line working. (Not an engineer so happy to be shotdown if I'm wrong)
 

Bald Rick

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I thought the case was more about flexibility than reliability. When on a four track railway and working on the lines, headspans require all power shutoff whereas gantries would allow two line working. (Not an engineer so happy to be shotdown if I'm wrong)

I'm afraid a sidewinder missile is heading up your tailpipe.

In multi-track areas with headspans, each line is usually separate electrically, and can be isolated individually. Most maintenance on the small part steelwork etc can be carried out the same as if it was on gantries. The maintenance issue is that working on the headspan itself is occasionally required (not normally the case for gantries, except for painting) and if the headspan needs adjustment then it may be the case that all lines need an isolation. But this is very rare.

Head spans were installed back in the day because they were cheaper and much less disruptive to install. The material cost was a bit cheaper, but they could be put up with a handful of blokes with ladders and this was often done between trains with the blokes crossing open lines with the cables which were rapidly fixed into position. No need for possessions, night working or expensive on track plant. Indeed the small part steelwork on head spans was sometimes also installed between trains, with the blokes left up there while trains went underneath. Of course in those days the safety regime was somewhat less stringent, and using the Midland Main Line as an example, the number of trains around in the middle of the day was about a third of what it is today.

Today we would need full possession of all lines to put up head spans, and almost certainly on track plant, so as you have to do that you may as well put up a gantry and get the performance benefit for the occasions the wires do come down.

It is also true to say that head spans do have a higher propensity to failure than gantries, even a simple pantograph * bird strike has the potential to break a headsman which can take all contact wires out of registration. And when there is a dewirement on a headspan, you must assume that the other lines are affected until inspected and proven clear, this is not the case on gantiries.
 

MrJamesBrown

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I thought the case was more about flexibility than reliability. When on a four track railway and working on the lines, headspans require all power shutoff whereas gantries would allow two line working. (Not an engineer so happy to be shotdown if I'm wrong)

What is the difference between a headspan and a gantry?
 

LNW-GW Joint

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What is the difference between a headspan and a gantry?

A headspan is a catenary wire stretched across the tracks between tall masts, supporting the OHLE wires.
A gantry is a rigid portal structure with a solid cross-member between (usually) smaller masts, doing the same job.
Headspans are cheaper and easier to put up (see Mr Rick's posts above), but gantries provide better support for the dangly bits.

I have still to see anything better than the light lattice-structure gantries on the 4-track sections of the original WCML electrification (south of Crewe).
Headspans were put up on the 4-track sections of the ECML, the MML south of Bedford, and the WCML north (mainly Warrington-Preston and around Carlisle). [Edit: And GWML Paddington to Airport Jn.]
Portal structures were used on the WCML and the GEML (some of which date from the 1930s).
We are waiting to see how the rest of the GWML is going to be kitted out.
Gantries have gone up near Reading.
 
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hassaanhc

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What is the difference between a headspan and a gantry?

Headspan:
640px-Otterington_railway_station_MMB_01.jpg

Image from http://commons.wikimedia.org/w/index.php?title=File:Otterington_railway_station_MMB_01.jpg

Gantry:
640px-MKcentral.JPG

Image from http://en.wikipedia.org/w/index.php?title=File:MKcentral.JPG

I'd never realised that it is headspans used on the London area GWML electrification (image of West Ealing Station).
 
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swt_passenger

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We are waiting to see how the GWML is going to be kitted out.
Gantries have gone up near Reading.

The planning environmental statements provided to the various planning authorities along the route are quite specific that all four track sections will be four track portals. Two track sections such as Didcot to Oxford are described as having single track cantilevers. Headspans are not mentioned with regard to main running lines, although they can be seen in the depot area west of Reading over the stabling sidings.

There's a load of relevant documentation on NR's website here: http://www.networkrail.co.uk/searchresult.aspx?q=great western electrification vol 1a
 
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hassaanhc

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A headspan is a catenary wire stretched across the tracks between tall masts, supporting the OHLE wires.
A gantry is a rigid portal structure with a solid cross-member between (usually) smaller masts, doing the same job.
Headspans are cheaper and easier to put up (see Mr Rick's posts above), but gantries provide better support for the dangly bits.

I have still to see anything better than the light lattice-structure gantries on the 4-track sections of the original WCML electrification (south of Crewe).
Headspans were put up on the 4-track sections of the ECML, the MML south of Bedford, and the WCML north (mainly Warrington-Preston and around Carlisle).
Portal structures were used on the WCML and the GEML (some of which date from the 1930s).
We are waiting to see how the GWML is going to be kitted out.
Gantries have gone up near Reading.

Gantries also have been used at the new flyover at Hayes & Harlington and where the Crossrail works between Ealing Broadway and Paddington have required, rest of the existing London-area stuff is Headspans.
 
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LNW-GW Joint

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Thanks for the link, very interesting. Portals it is.
I was foxed by the term DCL in the documents until I realised it meant the "Didcot to Chester Line". :)
The title pages include natty images of Pendolinos on the WCML.

I bet IKB didn't have to produce any of this for the original line...
--- old post above --- --- new post below ---
The Network Rail documents referenced above give the following dates for OLE construction (Vol 1A, p37):

Maidenhead-Reading April 2014-Jan 2015
Reading-Newbury Oct 2014-May 2015 (conventional)
Reading-Didcot Sept 2013-June 2014
Didcot-Oxford June 2014-Feb 2016 (weekends only, conventional)
Didcot-Wootton Bassett Dec 2013-Feb 2015
Wootton Bassett-Westerleigh July 2014-Mar 2015
Westerleigh-Patchway Sept 2014-July 2015
Bristol TM-Parkway June 2016-Oct 2016
Wootton Bassett-Thingley July 2015-Oct 2015
Thingley-Bristol TM July 2015-Mar 2016
Patchway-Severn Tunnel Jan 2015-July 2015

The document is dated October 2012, and the programme may well have changed (and has certainly slipped).
But it does give an idea of how the HOPS system will have to be deployed to complete electrification to Oxford/Newbury/Bristol by 2016.
The Welsh equivalent of the above does not give any intermediate dates before 2017 to reach Cardiff.
Another interesting piece is the selection of the operating base for the HOPS system.
It might have been based at Llanwern (Newport), but the electrification approval was at one point cut back from Swansea to Cardiff and so Swindon was the natural choice.
 
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Techniquest

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So without having to go through all 25 pages (I have some sort of life away from the forum! :lol:), what's the latest score with electrification of the Western?
 

MrJamesBrown

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A headspan is a catenary wire stretched across the tracks between tall masts, supporting the OHLE wires.
A gantry is a rigid portal structure with a solid cross-member between (usually) smaller masts, doing the same job.
Headspans are cheaper and easier to put up (see Mr Rick's posts above), but gantries provide better support for the dangly bits.

I have still to see anything better than the light lattice-structure gantries on the 4-track sections of the original WCML electrification (south of Crewe).
Headspans were put up on the 4-track sections of the ECML, the MML south of Bedford, and the WCML north (mainly Warrington-Preston and around Carlisle). [Edit: And GWML Paddington to Airport Jn.]
Portal structures were used on the WCML and the GEML (some of which date from the 1930s).
We are waiting to see how the rest of the GWML is going to be kitted out.
Gantries have gone up near Reading.


Thanks you guys :)
 

LNW-GW Joint

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So without having to go through all 25 pages (I have some sort of life away from the forum! :lol:), what's the latest score with electrification of the Western?

I'd say they were 6 months late, and are probably not yet up to the planned speed yet.
On the other hand, as the Channel Tunnel proved, you can be very late in the first year of construction and still catch up (at a cost).
 

Taunton

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A journey down the line a few days ago (end of June) showed almost nothing, rather surprising. All that was visible was a few masts (verticals only) east of Didcot and outside Reading, along with the new depot at Reading which was wired some time ago. The "high output" units were on their depot at Swindon but seem to be "no output" at present.

In contrast the new main line flyover west of Reading looked pretty complete structurally.
 

hassaanhc

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A journey down the line a few days ago (end of June) showed almost nothing, rather surprising. All that was visible was a few masts (verticals only) east of Didcot and outside Reading, along with the new depot at Reading which was wired some time ago. The "high output" units were on their depot at Swindon but seem to be "no output" at present.

In contrast the new main line flyover west of Reading looked pretty complete structurally.

I went Southall-Reading last week and apart from the approaches to Reading there was no obvious sign whatsoever of any electrification work being done. However there were trackside workers in various places and I'm not sure if they were doing any work related to electrification.
 

LNW-GW Joint

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I went Southall-Reading last week and apart from the approaches to Reading there was no obvious sign whatsoever of any electrification work being done. However there were trackside workers in various places and I'm not sure if they were doing any work related to electrification.

There are two lots of contractors/construction plant on the GW job.
Airport Jn-Maidenhead is Balfour Beatty (a Crossrail contract), and west of Maidenhead is Amey with the HOPS.
You'd expect to be seeing progress on both contracts now, using the same OHLE design but different construction gear and people.
 

Techniquest

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I'd say they were 6 months late, and are probably not yet up to the planned speed yet.
On the other hand, as the Channel Tunnel proved, you can be very late in the first year of construction and still catch up (at a cost).

Thanks for the catch-up, hopefully more solid evidence of electrification will be seen soon, otherwise the IEPs will get here with nowhere to run :lol:
 

76020

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I went Southall-Reading last week and apart from the approaches to Reading there was no obvious sign whatsoever of any electrification work being done. However there were trackside workers in various places and I'm not sure if they were doing any work related to electrification.

I travelled between Reading and London Paddington today and just east of Taplow Station on the up line there are about five steel piles that have been sunk so the Balfour Beatty boys have started on their bit. I did not see what is on the down line.
 

LNW-GW Joint

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I travelled between Reading and London Paddington today and just east of Taplow Station on the up line there are about five steel piles that have been sunk so the Balfour Beatty boys have started on their bit. I did not see what is on the down line.

Did a turn from Oxford to Paddington today.
I counted 41 masts between Moreton and Tilehurst, plus 151 bases (on the north side).
I make that 64% of the bases and 14% of the masts on this stretch (based on 15 structures per km).
The masts are quite light with a square section (no horizontal portals yet; if they are like those in the Reading station works they will look very "heavy").
Nothing to see Moreton-Didcot-Oxford or Reading-Maidenhead.
In the Reading station works, masts are going up on the new viaduct and round the triangle.
No droppers or signs of preparation for any wires yet, except partially inside the EMU depot.

The count of bases on the Crossrail stretch near Taplow is now about 14 on the north side, not far from Maidenhead bridge eastwards (nothing on the south side).
Balfour Beatty have work sites at West Drayton, Langley and Maidenhead.
The one at Langley is where the old oil terminal was, and has a stockpile of, well, piles.
There are also masts going up at the east end of North Pole depot, near where it will be connected to the GW main line.
 
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fgwrich

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Did a turn from Oxford to Paddington today.
I counted 41 masts between Moreton and Tilehurst, plus 151 bases (on the north side).
I make that 64% of the bases and 14% of the masts on this stretch (based on 15 structures per km).
The masts are quite light with a square section (no horizontal portals yet; if they are like those in the Reading station works they will look very "heavy").
Nothing to see Moreton-Didcot-Oxford or Reading-Maidenhead.
In the Reading station works, masts are going up on the new viaduct and round the triangle.
No droppers or signs of preparation for any wires yet, except partially inside the EMU depot.

The count of bases on the Crossrail stretch near Taplow is now about 14 on the north side, not far from Maidenhead bridge eastwards (nothing on the south side).
Balfour Beatty have work sites at West Drayton, Langley and Maidenhead.
The one at Langley is where the old oil terminal was, and has a stockpile of, well, piles.
There are also masts going up at the east end of North Pole depot, near where it will be connected to the GW main line.

Where the bases you saw still half in/half out of the ground? I counted 8 This evening which where standing quite tall out of the ground (I was passing on a HST at the time!) I did notice that Crossrail have put up masts going into Acton Depot as well for future electrified freight? and expanded some of the siding/retaining wall space in the OOC area and further along the GWML.
 

LNW-GW Joint

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Where the bases you saw still half in/half out of the ground? I counted 8 This evening which where standing quite tall out of the ground (I was passing on a HST at the time!) I did notice that Crossrail have put up masts going into Acton Depot as well for future electrified freight? and expanded some of the siding/retaining wall space in the OOC area and further along the GWML.

Yes indeed, some of them were "standing proud".
I'm not bright enough to know if that's because they haven't finished the piling, or whether they are in their final position.
There aren't many metal piles on the NW electrification, but some of those installed over Chat Moss were left with a length above the ground (and shorter masts).
I suppose it depends on the ground conditions.
On the TV route the sub-strata is chalk so you wouldn't have thought there would be a problem with piling it fully.
 

76020

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I travelled from Bristol TM to London Paddington today and piles have now appeared between Swindon and Didcot, there are about twelve on the four track section and the same amount on the two track section heading east towards Didcot.
There are around 40 masts installed between Didcot and Reading.
No more new piles around Taplow in the last few weeks, only a few either side of the station but I could only see the up line (northside).
On the new Reading flyover, masts are appearing on the western end.

On the signalling side there are new foundations for locations from Bristol all the way to Airport Junction, except between Didcot and Reading, with new locations from Chippenham to Airport Junction, except the above, no sign of any new signals except in the Reading area.

The new flyover at Airport Junction looks like an end to end structure now, but my view was marred by the existing flyover.

So they progressing nicely but Dec 2016/Spring 2017 will be here quicker than you think!:D:D:D
 
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fgwrich

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Last nights Night Riviera trip back showed to me that it's starting to slip behind - all MPVS parked up in Swindon with a few bits on and off, lot's of piles piled up at Swindon and Moreton Cutting with a few Masts and Arms stored in the latter, From what I could see in the dark of the night 34 Masts up between Didcot and Tilehurst but spread across both down fast and up slow - no particular ordering! More work seems to have happened in the Reading Triangle area though with masts up on the curve from Reading Station to Reading West, A large gantry just after the Oxford Road bridge and a few piles located behind the platforms awaiting masts.
 

gwr4090

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Last nights Night Riviera trip back showed to me that it's starting to slip behind - all MPVS parked up in Swindon with a few bits on and off, lot's of piles piled up at Swindon and Moreton Cutting with a few Masts and Arms stored in the latter, From what I could see in the dark of the night 34 Masts up between Didcot and Tilehurst but spread across both down fast and up slow - no particular ordering! More work seems to have happened in the Reading Triangle area though with masts up on the curve from Reading Station to Reading West, A large gantry just after the Oxford Road bridge and a few piles located behind the platforms awaiting masts.

Why do you think that its starting to slip. Do you know many masts should have been erected at this stage ?
 

fgwrich

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Because I'd have expected to have seen a little more work completed by now - I'll admit I wasn't looking for completed piles in the ground - it's a bit difficult to spot them in the dark at speed, but I would have expected to have seen a few more masts up by now and in more of a sequence than a few on the Down/Up in several different stretches of line, especially given that the original deadline for TV Electrification was December 2016/Early 2017.
 

LNW-GW Joint

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Why do you think that its starting to slip. Do you know many masts should have been erected at this stage ?

The OLE installation plan published in the Environmental Statement in October 2012 (on the NR web site) had a series of dates for various sections of line.
By now:
- Reading-Didcot should be complete
- work should be ongoing on Maidenhead-Reading and Didcot-Wootton Bassett
- Didcot-Oxford and Wootton Bassett-Westerleigh should recently have started
I'm sure they are working to an updated plan, but it's hard not to conclude from the lineside evidence that they are running late.
From the document: (5.9.31 p37)

OLE installation. This would include some works using conventional road-rail plant, but would be undertaken mostly by the HOPS, with its set of five ‗Consists‘ working in sequence, resulting in an overlapping programme of works along the 8 Contract Periods, for which the current expected dates are:
- Period 1 – Maidenhead to Reading – April 2014 to January 2015
- Period 2 – Reading to Newbury – October 2014 to May 2015, plus weekends only (conventional works) June 2014 to February 2016
- Period 3 – Reading to Didcot – September 2013 to June 2014
- Period 4 – Didcot to Oxford – June 2014 to February 2016 weekends only (conventional works)
- Period 5 – Didcot to Wootton Bassett – December 2013 to February 2015
- Period 6 - Wootton Bassett to Westerleigh – July 2014 to March 2015
- Period 6 – Westerleigh to Bristol Parkway and Patchway – September 2014 to July 2015
- Period 6 – Bristol Parkway to Bristol Temple Meads – June 2016 – October 2016
- Period 7 - Wootton Bassett to Thingley - July 2015 to October 2015
- Period 7 – Thingley Junction to Bristol Temple Meads –July 2015 to February 2016
- Period 8 – Patchway to Severn Tunnel – January 2015 to about July 2015
 

gwr4090

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The OLE installation plan published in the Environmental Statement in October 2012 (on the NR web site) had a series of dates for various sections of line.
By now:
- Reading-Didcot should be complete
- work should be ongoing on Maidenhead-Reading and Didcot-Wootton Bassett
- Didcot-Oxford and Wootton Bassett-Westerleigh should recently have started
I'm sure they are working to an updated plan, but it's hard not to conclude from the lineside evidence that they are running late.
From the document: (5.9.31 p37)

Thanks for that info. It seems that the HOPS plant commissioning has not met the original planned schedule.
--- old post above --- --- new post below ---
Just watched an item on HOPS on BBC South News on TV. Commissioning is now complete. It should be piling up to about 1 mile per night from now on, apparently.
 
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