Manchester - Liverpool Electrification

[CosherB]

I noticed yesterday that OLE gantries have been erected on the viaduct at Castlefield. They look quite substantial for 25KV; more so than the old 1500VDC ones on adjacent the ex-Altrincham line.

 

[MK Tom]

Does anyone have any pictures of this?

 

[WatcherZero]

 

[Lampshade]

At least they're not cantilever'ing the whole route like with the ECML.

 

[callum112233]

oh. Progress.

 

[175001]

A view from the back cab a few weeks ago.

 

[boing_uk]

Is it just me or do those structures look slightly over-engineered?

 

[CosherB]

Is it just me or do those structures look slightly over-engineered?

That was something I referred to in the opening post. They look to be more substantial than the old DC ones which had to support much heavier o'head lines.

I thought an advantage of high voltage AC was lighter OLE structures? Maybe they are usung these on the viaduct section as it's easier, though I'm pretty sure the Holmes Chapel and Dane (Congleton) and Stockport viaducts use lighter supports than these.

 

[Nym]

Erm...

Why are we complaining about something being stronger than it needs to be? Perhaps these structures will be housing transformers, breakers, feeders?

 

[CosherB]

Erm...

Why are we complaining about something being stronger than it needs to be?

Because they are more visually intrusive! Look at old pictures of the Woodhead line with its heavy DC OLE, and compare with, say WCML in Lune Gorge where the OLE is hardly visible in the landscape.

Perhaps these structures will be housing transformers, breakers, feeders?

What, all of them?

 

[sprinterguy]

Because they are more visually intrusive! Look at old pictures of the Woodhead line with its heavy DC OLE, and compare with, say WCML in Lune Gorge where the OLE is hardly visible in the landscape.

Inner city Manchester is a lot less picturesque than the Lune Gorge though. Personally, it reassures me that Network Rail appear to be using more substantial equipment that is more likely to withstand the demands of a high frequency suburban rail service compared to BRs' policy of using the most lightweight equipment possible to save on costs that they pursued in the early nineties.

 

[Nym]

Because they are more visually intrusive! Look at old pictures of the Woodhead line with its heavy DC OLE, and compare with, say WCML in Lune Gorge where the OLE is hardly visible in the landscape

Oh no, it will put of those comiting luid acts in the Castlefeild Viaduct area...

But yes, it could well be, and why would you want to remove future flexibility?

Theres going to need to be several tensioners remember, since there isn't space for them at Deansgate, so they'll be the fixed end, and they'll be tensioned further up.

 

[Schnellzug]

Is it just me or do those structures look slightly over-engineered?

maybe they're going back to the philosophy when the WCML was electrified of making it strong enough to withstand an earthquake and a hurricane simultaneously, which perhaps might be not altogether a bad thing seeing how flimsy some of the cheaper methods can be.
However, if this is what they're planning to do with the GWML, I'm not sure how sympathetic that'd be with Brunel's engineering ..

 

[hairyhandedfool]

If they put in the smaller posts and the wind picks up and the wires drop, everyone would be asking why stronger structures weren't put up, but as stronger ones are being put up, why not ask why lighter ones are not being put up.:roll:

 

[swt_passenger]

At least they're not cantilever'ing the whole route like with the ECML.

I think perhaps you must mean they aren't fitting headspans?

Isn't headspan damage generally the cause of the OHLE problems on the ECML?

 

[185]

Watcher, we need a SkyScrapercity thread to follow the progress.

 

[ainsworth74]

Personally, it reassures me that Network Rail appear to be using more substantial equipment that is more likely to withstand the demands of a high frequency suburban rail service compared to BRs' policy of using the most lightweight equipment possible to save on costs that they pursued in the early nineties.

Indeed, normally Network Rail is abused for 'gold plating' everything. However, this is one time where personally I say go ahead and buy the most substantial stuffy you can get a hold of!

Isn't headspan damage generally the cause of the OHLE problems on the ECML?

Yeah it's normally in those areas that the problems occur mostly because one wire being brought down often brings the whole lot down! It's perhaps worth noting that on the northern stretches of the ECML where it's all canterlivered and there are much higher winds, than down south, the wires come down much less often.

 

[aylesbury]

This is going back to the origanal spans on the WCML they are still going strong and unlike the ECML the wires generaly stay up unless a wayward pantograph pulls them down!

 

[WatcherZero]

Watcher, we need a SkyScrapercity thread to follow the progress.

Thread starts in 2010 but no visual progress really until this year.

http://www.skyscrapercity.com/showthread.php?t=1265187&page=18

 

[John55]

The portal structures have been appearing for a few weeks. When I first saw them I too was surprised how substantial they are. They appear to be heavier than equivalent structures from the 1950 & 60s on the WCML.

I was at a presentation a year or so ago when a NR engineer was explaining the problems that occur on the GEML out of Liverpool St where the overhead structures are so heavy that if it breaks (and especially if the masts are damaged) it is much more difficult to put back due to the sheer weight of metal involved.

Clearly there needs to be a balance between cost, robustness, maintainability and the visual impact, but good engineering does not involve putting up oversized and overweight structures which might even damage the viaduct!

 

[Ivo]

How long has this been present then? I can't believe I didn't see this on Saturday >.<

 

[175001]

They were put in during 4 sunday possessions in January.

 

[Xenophon PCDGS]

Shall we wait and see exactly how far this type of gantry is proposed to be erected, before making suppositions. Has anyone enquired about this matter and received a reply, so the official position can be made clear.

 

[brianthegiant]

Re whether the strcutures are OTT - once you've paid all your labour, plant etc costs, the increase in project cost between cantilevers and gantrys is probably marginal.

If you have a bt of spare structural capacity you can add extra feeders, etc later on if you need to. Adding /modifying structures later on would be much higher than putting in some spare capacity at the start, particularly in difficult to access location like a viaduct.

Politically it is harder to argue for higher maintenance spending than it is to argue for funds for capital investment. And in a market system with high labour costs where there is an increasing interest in the 'full lifecycle cost' so in some industries there is a trend towards building more robust systems in the beginning to reduce ongoing maintenance costs.

 

[lincolnshire]

Quality of mast,s on new electrification.
Remember back in the days of B.R. the electrification of the ECML was done by self funding from within the money given to B.R. to run the railways for the year, thats why everything had to be done on a shoestring budget. If the government is your banker and provider of money and the cost of running the railways is far higher than it was back in B.R. days, then there is no wonder that you can go for gold plated equipment for the o/heads.

 

[LNW-GW Joint]

I'm impressed that NR erected these gantries with no serious impact on services.
I expected a week's total closure at least!
I thought this would be a particularly difficult bit because of its location and height, on a 163-year-old structure.
I still can't figure out how they are going to splice the Ordsall Chord into the high, sharply curved viaduct (possibly a reason for the heavy OHL structures).

 

[scrapy]

That was something I referred to in the opening post. They look to be more substantial than the old DC ones which had to support much heavier o'head lines.

I thought an advantage of high voltage AC was lighter OLE structures? Maybe they are usung these on the viaduct section as it's easier, though I'm pretty sure the Holmes Chapel and Dane (Congleton) and Stockport viaducts use lighter supports than these.

Network Rail have plans to 'upgrade' the OHLE between Macclesfield and Kidsgrove following recent problems in high winds so this may involve proper metal gantrys similar to the ones at Castlefield in the future.

 

[OxtedL]

Anyone know how they got the gantries there?

 

[ole man]

The cantilevers on Macclesfield to Kidsgrove are circular masts, as for the pictures on at castlefield looks like either Headspans going up or will be UK1 style stove pipes, i was told that it might have Furrer and Frey equipment though, just have to wait and see, the possibilities are endless

 

[themiller]

Furrer and Frey equipment

F&F equipment is to be designated NR1, I believe (at least on GWML).