Great Western Electrification Progress

[jimm]

Which it makes it rather odd that Rail have also run the 'scare story' implying that when the 'first EMUs' arrive there'll be no wires to use them under. Perhaps Rail really are unaware that Paddington to Hayes & Harlington (and beyond to the airport) is already wired...

Yes, the article does contradict itself within a few paragraphs but I think it's safe to assume Mr Hopwood knows what he is talking about in this case and the first GWR emu services are just a few months away.

Also the comment that the IEPs on diesel power will be slower than the planned electrics, so they will have to invent an interim timetable.

What he actually said was "they're not as fast accelerating in diesel mode".

And Roger Ford now seems pretty convinced after a series of Parliamentary written answers from the DfT that the the 800s will be able to run at 125mph in diesel mode, though he says that will presumably be subject to revision of the maintenance/lease costs if the engines have to be worked harder than anticipated, given that the routes they will normally work in diesel mode don't allow for anything much over 100-110mph.

On the basis that Paddington-Maidenhead and Reading or Tilehurst to Didcot will all be wired by the time the first 800s enter service in spring 2017, with any remaining electrification gap in the Thames Valley presumably going to be plugged fairly soon afterwards, the 800s will be doing plenty of miles using 25kv, as that amount of wiring would already account for a big part of the GWML mileage passed for 125mph.

Apart from the Swindon station area, wiring Didcot to Bristol Parkway should be pretty straightforward and will account for almost all of the rest of the 125mph zone apart from Wootton Bassett to Chippenham.

 

[Philip Phlopp]

Yes, the article does contradict itself within a few paragraphs but I think it's safe to assume Mr Hopwood knows what he is talking about in this case and the first GWR emu services are just a few months away.



What he actually said was "they're not as fast accelerating in diesel mode".

And Roger Ford now seems pretty convinced after a series of Parliamentary written answers from the DfT that the the 800s will be able to run at 125mph in diesel mode, though he says that will presumably be subject to revision of the maintenance/lease costs if the engines have to be worked harder than anticipated, given that the routes they will normally work in diesel mode don't allow for anything much over 100-110mph.

On the basis that Paddington-Maidenhead and Reading or Tilehurst to Didcot will all be wired by the time the first 800s enter service in spring 2017, with any remaining electrification gap in the Thames Valley presumably going to be plugged fairly soon afterwards, the 800s will be doing plenty of miles using 25kv, as that amount of wiring would already account for a big part of the GWML mileage passed for 125mph.

Apart from the Swindon station area, wiring Didcot to Bristol Parkway should be pretty straightforward and will account for almost all of the rest of the 125mph zone apart from Wootton Bassett to Chippenham.

IEP on diesel will be capable of matching HST diagrams, and as you say, 100mph on diesel has been chosen because once electrification is completed, the remaining routes are all 100mph (with a little bit of 110mph in South West England, from memory).

 

[Domh245]

Pictures may stimulate some discussion 're gw electrification.
http://www.railengineer.uk/2013/04/10/has-third-rail-had-its-day/
And
http://www.architectsjournal.co.uk/...ad-lines-contest-revealed/8662318.fullarticle

Both of those articles are over a year old, and have been discussed on here in some way shape or form.

In short:
Yes, 3rd rail has had it's day
None of those designs would work, or present no advantage over current systems
(never trust an architect!)

 

[HowardGWR]

I assume there will be a temporary penalty for Bi-mode trains climbing from Bath to Wootton Bassett though. How that affects the proposed timetable, kindly referenced by @SWT - perhaps only a couple of minutes.

 

[Philip Phlopp]

I assume there will be a temporary penalty for Bi-mode trains climbing from Bath to Wootton Bassett though. How that affects the proposed timetable, kindly referenced by @SWT - perhaps only a couple of minutes.

It shouldn't do, but until there's test running and modelled behaviour is reproduced, it'll be difficult to know for certain.

As it stands, with the engines fully 'slugged' as Roger puts it, power to weight is significantly ahead of HST sets, and there's modern traction equipment and distributed drive to significantly enhance acceleration and gradient climbing, but on the downside, hotel power requirements are significantly higher than HST, so on balance, the two types should be fairly evenly matched.

If agreement can't be reached for full 750kW operation of the power units, then performance against timetable will need to be reassessed and a slower timetable agreed. The behaviour of the 5 car units will also need to be taken into account, if they're to be used in diesel mode, as they've got higher frontal drag to power ratios to take into account. The interim timetable would need to take this into account if it's significant, but I doubt it will be.

 

[swt_passenger]

Pictures may stimulate some discussion 're gw electrification.

http://www.architectsjournal.co.uk/...ad-lines-contest-revealed/8662318.fullarticle

Not exactly practical solutions, were they? They should have asked engineers instead of architects...

 

[Philip Phlopp]

Not exactly practical solutions, were they? They should have asked engineers instead of architects...

They've treated OLE masts as if they're street lights, which is an enormous mistake.

They're all 'viable' but they all lack some or all the necessary adjustment needed to correctly position the contact wire and catenary wire in the correct position to set the stagger appropriately, and they all appear to lack a height adjustment, so will need to be cut on site, which will lose the galvanised coating at the foot, and they'll fall down in a handful of years.

Electrification masts are worse than signal posts for trains to run over, so we really don't want anything where the galvanised coating is lost on site through sawing, burning, cutting etc.

They also fall broadly into two camps re their catenary geometry - some are like the old Mk.1/Mk.3 OLE system which uses a variety of different catenary cantilever elements to compensate for variations in the the mast to track distance. We don't want that, we want man in a van capable equipment, one or two standard designs which can be adjusted, not 10 or 20 different designs which take time to come from store or need to be made to order.

The others have none of the adjustment needed, they would need precise (and difficult/impossible) mast placement and any track geometry changes would need new masts or catenary arms.

Oh, and I see lots of box designs, which are potential inspection problems, in addition to being expensive to manufacture and difficult to galvanise correctly (they can trap air bubbles and be poorly galvanised, if the company isn't good at what they do).

I see absolutely no reason to move away from RSJ section and square 4/6 bolt footings, with cantilever elements which can be bolted at any height, then adjusted out horizontally to the correct position to provide the correct stagger.

 

[HowardGWR]

I see absolutely no reason to move away from RSJ section and square 4/6 bolt footings, with cantilever elements which can be bolted at any height, then adjusted out horizontally to the correct position to provide the correct stagger.

What did you think of the emphasis in MR (Walmsley I think) on 6 bolt vs 4 bolt (as though that was the reason for significant cost over-run)? I found the contention rather trite, frankly, although I am an amateur of course.

Edit, sorry -spelt his name wrongly

 

[Philip Phlopp]

What did you think of the emphasis in MR (Walmsely I think) on 6 bolt vs 4 bolt (as though that was the reason for significant cost over-run)? I found the contention rather trite, frankly, although I am an amateur of course.

Not read MR for the last couple of months. Just getting a wee bit fed up with the knives being out for the GWEp from people who don't quite get why we can't do things the way British Rail did on the ECML.

 

[HowardGWR]

Not read MR for the last couple of months. Just getting a wee bit fed up with the knives being out for the GWEp from people who don't quite get why we can't do things the way British Rail did on the ECML.

In fairness, they get a lot right, but on this issue of cost increase, I have yet to read, even from those who should know, any credible reason* for why the original estimate was so wrong, other than incompetent estimation.

*The only one I did come across, we discussed here earlier, which was the payments to TOCs (mainly FGW/gWr) for the over-runs on line occupation and disturbance through signalling severance. I would be very interested to know what this total cost has been and remember, those payments went straight into First's coffers, in other words a straight transfer from taxpayer to First shareholders.

 

[Philip Phlopp]

In fairness, they get a lot right, but on this issue of cost increase, I have yet to read, even from those who should know, any credible reason* for why the original estimate was so wrong, other than incompetent estimation.

*The only one I did come across, we discussed here earlier, which was the payments to TOCs (mainly FGW/gWr) for the over-runs on line occupation and disturbance through signalling severance. I would be very interested to know what this total cost has been and remember, those payments went straight into First's coffers, in other words a straight transfer from taxpayer to First shareholders.

There's a lot of people who want to know how much First's shareholders have been paid, effectively by the taxpayer in compensation for not being able to pay taxpayers some money for the privilege of running a train.

 

[nlogax]

There's unsurprisingly an enormous reluctance to touch any sections of track where the precise location of signal wiring is unknown OR where the signalling wires are judged to be at or near 'life expired' status as piling can cause failures in the wiring, even if they're troughed.

I did Paddington > Bath Spa today, was amazed at the almost total lack of anything 'visible' west of Didcot beyond occasional bridge rejig and embankment work. I know tunnel trackwork has been lowered and there's the small test section north of the London end of Swindon's platforms, but do you know when will pilings and uprights will finally make an appearance on this section? That's a 50+ mile stretch that feels someway behind the rest of the project - is this all related to the hidden cabling issue or just part of the original timetable?

 

[Clarence Yard]

Well First Group shareholders haven't been paid anything for a few years now, that's why the stock isn't gaining weight - investors want their dividends and are not happy when they don't get them.

The amount that FGW has been paid in schedule 4 and 8 will only be a tiny part of the financial over run. These payments are regarded by TOCs as their business interruption insurance as they still have substantial outgoings to pay for (including to the DfT and NR!) irrespective of whether they run trains or not.

I think the real reason the costs have escalated are pretty clear and have been mentioned here before. The scheme has suffered from scope creep, thereby increasing costs at certain locations and is also having to be done by more time consuming and expensive methods than originally planned.

 

[Philip Phlopp]

I did Paddington > Bath Spa today, was amazed at the almost total lack of anything 'visible' west of Didcot beyond occasional bridge rejig and embankment work. I know tunnel trackwork has been lowered and there's the small test section north of the London end of Swindon's platforms, but do you know when will pilings and uprights will finally make an appearance on this section? That's a 50+ mile stretch that feels someway behind the rest of the project - is this all related to the hidden cabling issue or just part of the original timetable?

Someone will probably know more than I do on the day to day work plans - lots of work pencilled in for Christmas though.

 

[HowardGWR]

The amount that FGW has been paid in schedule 4 and 8 will only be a tiny part of the financial over run.

We still don't know what it is though.

I think the real reason the costs have escalated are pretty clear and have been mentioned here before. The scheme has suffered from scope creep, thereby increasing costs at certain locations and is also having to be done by more time consuming and expensive methods than originally planned.

You might think that, but 'I could certainly comment'. We don't have anything other than a set of vague utterances by Mr Carne with no breakdown of the cost of these increases in any credible detail. He must know what he agreed with contractors and why he had to pay more. Nobody is going to kid me that a supplier submits a bill with 'I'm sorry but it's now three times more than we agreed, but I can't explain why, so, nevertheless will you kindly cough up please' on the invoice.

 

[Clarence Yard]

Well the fact his state of the art kit couldn't be used didn't help. Lovely to look at though!

 

[deltic08]

If they introduce IEPs on the current timetable it's likely they will run via Chippenham with wires as far as Didcot or possibly Swindon.
But at that stage the route into Bristol doesn't matter.
I think the expectation now is that wiring the Badminton route to Bristol Parkway will follow, at which point they can claim to have "reached Bristol".
Being able to reach the IEP depot at Filton under electric power is also an important milestone.
With Swindon resignalling soon to be completed, wires could also reach Chippenham (Thingley Jn) on the Bath route.
Some solution at Bristol TM is needed before either route can be used electrically into the city.
Will they reach Cardiff before Bristol TM!? Milestones awaited.

With three possibilities, I didn't know how the scheme would progress beyond Wootton Bassett Junction and when IEPs would be introduced with regard to wiring progress. Would all three routes progress simultaneously or concentrate on one route to completion before starting on the next and so on to Cardiff eventually.
Bristol TM via Parkway first does seem logical with regard to both Filton depot and shortest journey time.
Are you speculating or do you have inside knowledge?

 

[LNW-GW Joint]

I did Paddington > Bath Spa today, was amazed at the almost total lack of anything 'visible' west of Didcot beyond occasional bridge rejig and embankment work. I know tunnel trackwork has been lowered and there's the small test section north of the London end of Swindon's platforms, but do you know when will pilings and uprights will finally make an appearance on this section? That's a 50+ mile stretch that feels someway behind the rest of the project - is this all related to the hidden cabling issue or just part of the original timetable?

There are actually plenty of piles in between Didcot and Uffington (about half way towards Swindon).
They then peter out by Shrivenham and nothing then until approaching Wootton Bassett.
And then nothing west of Wootton Bassett, but there are signs of preparation on the Parkway route.
I think the gist is that they are not working in areas which have not been resignalled.
There are piles near Pilning and Llanwern beyond Parkway, where resignalling is finished.
Nothing at all on the route via Bath.
--- old post above --- --- new post below ---

Are you speculating or do you have inside knowledge?

Just speculating, based on trips up the line from Newport, plus the apparent "no piles before resignalling" policy.

 

[deltic08]

On the basis that Paddington-Maidenhead and Reading or Tilehurst to Didcot will all be wired by the time the first 800s enter service in spring 2017, with any remaining electrification gap in the Thames Valley presumably going to be plugged fairly soon afterwards, the 800s will be doing plenty of miles using 25kv, as that amount of wiring would already account for a big part of the GWML mileage passed for 125mph.

Apart from the Swindon station area, wiring Didcot to Bristol Parkway should be pretty straightforward and will account for almost all of the rest of the 125mph zone apart from Wootton Bassett to Chippenham.

Bimode IEPs will be the saviour of Network Rail and the DfT. Without this invention it would have been egg on their faces.

It seems the pans will be up and down like a fiddlers elbow for an undisclosed time period with all these gaps beyond 2016.

 

[jimm]

I did Paddington > Bath Spa today, was amazed at the almost total lack of anything 'visible' west of Didcot beyond occasional bridge rejig and embankment work. I know tunnel trackwork has been lowered and there's the small test section north of the London end of Swindon's platforms, but do you know when will pilings and uprights will finally make an appearance on this section? That's a 50+ mile stretch that feels someway behind the rest of the project - is this all related to the hidden cabling issue or just part of the original timetable?

If anyone wants to know what work is going on where and when, then just go to this page on the Network Rail website http://www.networkrail.co.uk/great-western-route-modernisation/ and click on the various areas listed under the heading Local work updates. There is piling work taking place around Didcot and at various places further west this weekend, as well as between Maidenhead and Reading.

Bimode IEPs will be the saviour of Network Rail and the DfT. Without this invention it would have been egg on their faces.

It seems the pans will be up and down like a fiddlers elbow for an undisclosed time period with all these gaps beyond 2016.

I doubt that lots of gaps are feasible electrically, given that the wires need to be hooked up to a feed from the National Grid.

A 'Maidenhead/Reading gap', if there is one for a period of time, is possible because there is a feed at the London end for the original electrification to Heathrow, while the new main feed at Didcot can power the wires towards Tilehurst - which is how this section can be set up for GWML test running of the 800s.

But I think the main feed in Wiltshire is going to be in the Chippenham/Melksham area, so if wiring of the Chippenham-Bath-Bristol TM arm is left for later, thus delaying the power supply from here, then to reach Bristol Parkway and the Severn Tunnel using 25kv you will probably need to have the whole route from Didcot through Swindon wired up so it can use power from Didcot.

Perhaps someone with the necessary technical knowledge - Philip Phlopp? - can confirm this.

 

[Philip Phlopp]

If anyone wants to know what work is going on where and when, then just go to this page on the Network Rail website http://www.networkrail.co.uk/great-western-route-modernisation/ and click on the various areas listed under the heading Local work updates. There is piling work taking place around Didcot and at various places further west this weekend, as well as between Maidenhead and Reading.



I doubt that lots of gaps are feasible electrically, given that the wires need to be hooked up to a feed from the National Grid.

A 'Maidenhead/Reading gap', if there is one for a period of time, is possible because there is a feed at the London end for the original electrification to Heathrow, while the new main feed at Didcot can power the wires towards Tilehurst - which is how this section can be set up for GWML test running of the 800s.

But I think the main feed in Wiltshire is going to be in the Chippenham/Melksham area, so if wiring of the Chippenham-Bath-Bristol TM arm is left for later, thus delaying the power supply from here, then to reach Bristol Parkway and the Severn Tunnel using 25kv you will probably need to have the whole route from Didcot through Swindon wired up so it can use power from Didcot.

Perhaps someone with the necessary technical knowledge - Philip Phlopp? - can confirm this.

Thingley Junction, fed from the National Grid at Melksham. Didcot is the other new feeder on the England side, and there's the existing supply for the Paddington to Stockley junction electrification.

 

[snowball]

Is there a source of info on locations of feeder points throughout the electrified network? The Sectional Appendix shows locations of neutral sections - I think some of those are feeder points but at least equally many are just track sectioning points or autotransformer stations.

 

[Philip Phlopp]

Is there a source of info on locations of feeder points throughout the electrified network? The Sectional Appendix shows locations of neutral sections - I think some of those are feeder points but at least equally many are just track sectioning points or autotransformer stations.

The environmental statements have them, and there are planning applications available for them, if you know which councils to then look at.

 

[edwin_m]

Thingley Junction, fed from the National Grid at Melksham. Didcot is the other new feeder on the England side, and there's the existing supply for the Paddington to Stockley junction electrification.

Presumably if the wiring is complete from Wootton Bassett to Thingley then power can be passed through it to feed the section from Wooton Bassett to Parkway. This strikes me as leaving Parkway a bit far from any feeder until the wires are extended into Wales, but perhaps acceptable with a 2x25kV system and with all the trains initially being able to revert to diesel power if there is a problem.

 

[Class 170101]

It seems the pans will be up and down like a fiddlers elbow for an undisclosed time period with all these gaps beyond 2016.

I hope the pantographs, OLE and trains are up to this much lifting and raising of pantographs, particularly as it seems more than was originally planned.

 

[HowardGWR]

If anyone wants to know what work is going on where and when, then just go to this page on the Network Rail website http://www.networkrail.co.uk/great-western-route-modernisation/ and click on the various areas listed under the heading Local work updates. There is piling work taking place around Didcot and at various places further west this weekend, as well as between Maidenhead and Reading.

One assumes NR is keen to keep these reports up to date, especially as they involve local consultation. With that in mind, the Filton bank planned activities are not exactly zooming ahead it would appear. The renewal /replacement of the viaduct over Stapleton Road onwards over the River Frome and M32 will be a major job, for instance. Also, looking at Bath to Bristol, there is the whole stretch from Keynsham to St Annes along the shelf viaducts next to the Avon and including through two remaining tunnels, one very long. NR must be pleased that the GWR opened out another three of them, back along!

 

[deltic08]

I hope the pantographs, OLE and trains are up to this much lifting and raising of pantographs, particularly as it seems more than was originally planned.

This is exactly what I was thinking when I typed my post. Wear and tear. Not that difficult to change a full pan though.

 

[AM9]

This is exactly what I was thinking when I typed my post. Wear and tear. Not that difficult to change a full pan though.

Well Brecknell-Willis pantographs have been in regular use on routes where pantographs are raised and lowered up to 20 times per day, (think classes 319, 377, 378, 387 & 395), so unless the original plans for those on the class 800s assume a service action more than once per week, they should last between maintenance operations for the early part of their lives.

 

[jimm]

I hope the pantographs, OLE and trains are up to this much lifting and raising of pantographs, particularly as it seems more than was originally planned.

Are we talking about well-engineered trains, designed for a good 30 years of working life, or some delicate flower?

The bi-modes will be spending a lot of time running to and from the Cotswold Line, Cheltenham and Weston-super-Mare/Taunton in the normal course of their working lives for many years, requiring a lot of changes of power mode during a single working day if a diagram keeps a set shuttling up and down between London and Worcester from early morning until late evening - so Hitachi and Brecknell-Willis might just have made allowance for this at the design stage.

And the Series 1 catenary is deliberately designed to be more robust than previous kit used in the UK.

 

[LNW-GW Joint]

I'm not sure we have had services which require pan up/down more than once on a single journey though.
Maybe for a period on NLL services (3rd rail at the west and east ends, AC in the middle) before they were cut back to Stratford.
Let's hope the first service wiring is Stockley-Didcot and not some discontinuous sections in between.
We can also look forward to pan up/down at speed on the Didcot avoiding line - just like Dollands Moor used to be on Eurostar.