Swindon to Kemble re-doubling - ongoing discussion and updates

[whole diary]

[ChrisB]

Given that the Electric Spine scheme apparently doesn't include electrifying Nuneaton to Leicester,

Check out the quoted text from Narkoman above....it is included

Sorry, ellendune, but if this gets hived off, my post will go too!

[paul7575]

Given that the Electric Spine scheme apparently doesn't include electrifying Nuneaton to Leicester,

Check out the quoted text from Narkoman above....it is included

That's not the impression I get.  Nuneaton is already electrified of course, and Leicester will be, but not the line between the two places.  As I tried to explain earlier, Leamington > Coventry > Nuneaton > Leicester is not a practical route for through freight trains, as it would require reversal and the loco to change ends.

DfT^» (Department for Transport - about) published a 2019 electrification map (end of CP5^▸ (Control Period 5 - the five year period between 2014 and 2019) summary) a while back and that doesn't show Nuneaton - Leicester:

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/3647/map-hlos-electrification.pdf

I suggest it would only become useful for electric freight services as part of a future Felixstowe to West Midlands electrification project.

(I'm also thinking this topic drift might be better somewhere else, perhaps in 'the wider picture' board...)

Paul

[ChrisB]

You may be right - the map linked to that quote I mentioned is here -

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/3644/map-all-schemes.pdf

and doesn't show that either, even though it's mentioned in the text.

[TonyK]

We have strayed a bit, but it is interesting. It is correct to say that 25KV offers advantages over 750 V DC^▸ (Direct Current). Transmission losses are lower, because high voltage AC can be transmitted at lower currents, with transformers on the train stepping down the voltage and upping the current for the motors and other equipment. DC current cannot easily be transformed in the same way, so third rails and OHLE tend to carry the power at a current that will deliver what the motors need. Transmission losses are proportional to the square of the current,  meaning that more feeder stations are needed on 3rd rail DC than on AC, using much thicker cables to carry the current to the rail than is the case on overhead systems. Otherwise, at the end of a long stretch, the current and / or voltage drop, causing lower performance. Third rail systems may be cheaper to install, I don't know. But what is saved on overhead infrastructure will be lost in lots of other ways. After the icing problems of last winter, I heard a NR^» (Network Rail - home page) spokesman say that if they were starting electrification now, third rail would not see light of day.
Hopefully, the Swindon to Cheltenham via Kemble line will be electrified to keep this on thread.

[onthecushions]

The argument for replacing 750Vdc with 25kVac overhead springs from the normal replacement costs of dc (33kV lineside cable in trough, substations every 3.5 - 5 miles and TPH^▸ (trains per hour)'s in between) being about the same as for a completely new installation, including clearances etc of OLE^▸ (Overhead Line Equipment, more often "OHLE"). Energy use and maintenance costs are considered lower, hence the move to convert.

As the Swindon - Kemble line dualling has involved relaying or slewing most track, the clearances on this section at least should be satisfactory. If NR^» (Network Rail - home page) find the justification and money for the freight links North of Sheffield to the ECML^▸ (East Coast Main Line) system at Doncaster and Moorthorpe, this may well speed up XC^▸ (Cross Country Trains (franchise)) wiring and hence the infill of our Standish Jn - Swindon link.

OTC

[Railfriend]

Just wondering if anyone might have travelled the line in the last week or so and could give a few brief comments on how the work is going!  Best wishes to all for Christmas and the coming year.

[patch38]

Four month delay announced today:

http://www.bbc.co.uk/news/uk-england-26067520

[ChrisB]

Not surprising if they need those engineers in the flood-hit areas for urgent repairs

[wabbit]

A pity, but understandable if the people are being diverted to re-connect the West Country.

[bobm]

It seems the delay will now mean the signalling on the line will be handed over to the Thames Valley Signalling Centre at Didcot at the end of August at the same time as control for the rest of Swindon panel area moves there.

[quedgeley2002]

With the onset of the lighter mornings and evenings it is easier to see what progress is being made with the redoubling work. So here is a quick update of what can be seen from the daily commute!

Starting at the Kemble end various new bases and ground structures have been laid for signals and line side cabinets on the Sapperton side of the station. Presumably this is to even out the signal spacing to the new sections already installed and in operation. At Kemble itself other than the signal base prep little has been done. Moving southwards and work to relocate the cable runs is in progress in the tunnel and beyond but other than that no trackbed works have taken place. The second line in the 'down' formation is in place from about two miles beyond the tunnel and continues past Oaksey towards Minety before it runs out. At Minety crossing a large new concrete base has been built and during this week a large metal box has appeared (larger in size than the crossing control box) presumably to house electronics as it has a cooling fan at one end. The second track has been laid in some parts but at Minety village and beyond is where the majority of the excavation and trackbed prep work is currently happening.  There must be a few miles of temporary lineside lighting installed, it seems to go on forever!

Towards Purton there is some significant drainage prep work going on and after all of the rain it is very wet in some areas. The work seems to end a couple of miles from Purton crossing where the current line crosses from the up formation to the down.  Little work has been done around the crossing area. Towards Swindon with the second line already in place little remains to be done since the major possession last August

At Loco Yard Junction a number of signal and cabin bases have been installed. The area behind B&Q has started to receive materials and equipment probably in anticipation of the completion of the cross over works and the removal of the double line to single line turnout.     

The line between Swindon and Gloucester will be closed on Saturday 12th April and Sunday 13th April. On Monday 14th April and Tuesday 15th April the line will be closed between Swindon and Kemble with the hourly shuttle running from Kemble to Gloucester and Cheltenham. For the following Easter weekend the line is again completely closed on Friday to Sunday 18th to 20th April. Presumably this will allow for some of the major works to be undertaken before the final push in August!

The new footbridge half a mile or so west of Stroud station is now open and what a grand structure it is complete with LED lighting and long slopes. It has been built high enough to allow overhead wires should we see electrification in the future!

[Railfriend]

Thanks for the update, Quedgeley.

Seems as if there is still a great deal to be done before completion.  What with the extensive damage to the rail network by recent storms, such as on the south coast, I wonder if Swindon-Kemble will be completed by the end of the summer.  Perhaps the end of 2014 is more realistic.

[Railfriend]

A few recent photos of the redoubling here:

http://www.rmweb.co.uk/community/index.php?/topic/63590-swindon-kemble-re-doubling/

[ellendune]

Some more photos on Twitter from FGW^▸ (First Great Western)

https://twitter.com/FGW/status/456031022552203264/photo/1

https://twitter.com/FGW/status/456030738874630145/photo/1

Not sure how to embed the pictures

[tom m]

Not sure I would like to be the driver of this train