Great Western Main Line electrification - ongoing discussion

[whole diary]

[grahame]

I am delighted to read "techie" posts provided they don't drown the general content. I can choose to skip them if I want, whereas my choice of whether to read or not would be taken away from me if the post wasn't made.

Although I started with rail "stuff" in 2005 as a clueless amateur, I have learned a bit over the years and I'm fully aware that some of my posts may be regarded as long, dry, techie by some / many.  ok; but I'll try to explain them, and I'll keep them coming both as a record, to help those who are interested, and to receive feedback so that I'm slightly less clueless next time around.

[Chris from Nailsea]

Following on from grahame's previous post, I also welcome many of the more 'technical' posts from our expert members on topics such as this one, as they try to explain 'why' something is done, relative to 'what' is happening.

However, in view of the sheer size of this topic (and the fact that I'm on holiday for a week from now and therefore allegedly have time on my hands ),  I'll have a look at how I could possibly split this particular topic into two versions - one for a more general discussion, and the other for our very technically qualified members to give full flight to their fascinating discussions. 

Both versions of this particular subject will obviously be readable by all, but everyone will hopefully then be able to decide to what level of detail they want to read.

CfN. 

[chuffed]

That is a most helpful response Chris. Thank you in advance as I can see it will be time consuming. I would suggest that anything with figures and impenetrable acronyms and formulae goes into the techie section ! 

[bobm]

The 3187 description has been stuck in there since the signalling 'commissioning' at xmas/new year 2016/2017   I think II told us in another thread that the physical construction hasn't been completed yet.  Anybody got a photograph as it would be nice to see whats been done at Maidenhead (no good looking out of a train window at 125mph)? 

No photos sadly, but I can confirm the current state of play:

1) Station area:  Wires up throughout station area (and now assumed live) except for the London end of Platform 5 through to Maidenhead East Junction.
2) Turnback siding:  Wires are up on the turnback siding and signalling is installed, but there's no track beyond the S&C^▸ (Settle and Carlisle ) as yet - I heard it was to be installed during April, so presumably Easter weekend.
3) Stabling sidings:  No wires on any of them yet, though all other OHLE fixtures and fitting seem to be installed.  First two sidings are 'open' and signalled, the others all have rails and are ballasted but signalling work remains to be installed.

A few photos - as best as can be obtained from a moving turbo - but at least it had clean windows!

[SandTEngineer]

Bobm, thanks for posting those photographs. You must have been crawing past on a (possibly) delayed HST^▸ (High Speed Train) 

[bobm]

No it was a turbo pulling out of Maidenhead for Reading - it *was* two minutes late.  In this particular case that was just as well or I would have missed it!

[Chris from Nailsea]

That is a most helpful response Chris. Thank you in advance as I can see it will be time consuming. I would suggest that anything with figures and impenetrable acronyms and formulae goes into the techie section ! 

I'm still working on this project, where I've adopted a fairly pragmatic approach that, if any post (or series of posts) isn't specific to the Great Western Main Line, it will probably go into the separate technical discussion.

So far, it seems to have worked rather well. 

[TonyK]

Mind you, a quick look at bobm's photographs, above, gives an insight into the very complex nature of the modern railway. There are so many different scientific disciplines involved just in the structures shown, in both the theoretical and the practical sectors. Metallurgy, electrical engineering, geology, the chemists who decide the formulation of the paint, the makers of the insulators, stress engineering, the guys who decide the optimum shape of the gantrys are just a few whose work is shown.

As a country, we need to make sure these skills are available and improving. Post-Brexit, we may find a gap.

[TonyK]

I drove along the M4 yesterday, to somewhere I can't get to by train. There were posts up for the electric stuff on both sides of the track where the motorway crosses the railway up near Royal Wootton Bassett.

[NickF]

I drove along the M4 yesterday, to somewhere I can't get to by train. There were posts up for the electric stuff on both sides of the track where the motorway crosses the railway up near Royal Wootton Bassett.

Additionally there are a number of posts up where the railway crosses the A429 road, near Hullavington, some both sides, some just one side, and there seems to be the odd gap here and there where it looks like one is missing.

[Bmblbzzz]

I noticed a surprising (to me!) number of posts up between Cardiff Central and STJ^▸ (Severn Tunnel Junction railway station) yesterday morning. Probably more between STJ and the Tunnel too, but I got off there.

[Noggin]

I drove along the M4 yesterday, to somewhere I can't get to by train. There were posts up for the electric stuff on both sides of the track where the motorway crosses the railway up near Royal Wootton Bassett.

Additionally there are a number of posts up where the railway crosses the A429 road, near Hullavington, some both sides, some just one side, and there seems to be the odd gap here and there where it looks like one is missing.

I believe that where you see them just on one side they are quite likely to be two-track cantilever structures.

[BBM]

Wiring now appears to be complete at the east end of Sonning Cutting where I took a couple of photos today:

[Electric train]

Wiring now appears to be complete at the east end of Sonning Cutting where I took a couple of photos today:

Energisation of the Maidenhead - Reading OLE^▸ (Overhead Line Equipment, more often "OHLE") is due in August 17, with I believe through Paddington - Reading electrics locals in the September timetable.

I must emphasise the OLE in its present state is dangerous to approach or touch

[bobm]

I must emphasise the OLE^▸ (Overhead Line Equipment, more often "OHLE") in its present state is dangerous to approach or touch

The old maxim, treat every wire as though it is live.  (or in the politician's case treat every microphone as though it is live)