ECML OHL - in need of renewal?

[CallySleeper]

It seems like in recent years I have been caught up too many times over in disruption involving the ECML and downed wires. It might just be me, in which case I apologise, but it seems that aside from occasions influenced by external circumstances (eg the weather brought them down) I hear about this issue more often on the ECML than anywhere else, and usually on the southern half of this line. How old is the infrastructure here? I don't think I've really heard of any major issues on a more-than occasional basis on lines such as WCML which have not so long ago been upgraded.

Is it just me, then, or is the OHL on the ECML in need of renewal to prevent what seems to be these more-than-just-occasional major disruptions occuring?

Again, if is just me, then apologies.

 

[Eagle]

There are loads of wire problems on the WCML too, again usually on the southern end. It's not just the ECML that has difficulties.

 

[SkinnyDave]

It seems that the ECML has more OHLE problems?

Is there anyway of comparing stats?

 

[ainsworth74]

The thing with the ECML is the widespread use of headspans (two metal poles with wires strung between them) means that when the wires do come down it's often much more significant than on the WCML which avoids their use entirely. With headspans when one line's wire come down it often brings down the others which isn't such an issue with cantilever or full gantry type supports.

 

[tbtc]

What we really need is some bi-mode trains to replace the HSTs/ 225s...

The problem is that we tend to hear about problems in a certain area because we've heard about problems in that area before - look at how many (minor) level crossing accidents get mentioned in the fortnight shortly after a fatal one.

So its hard for me to say whether the ECML problems are above average in reality, and (if they are above average) whether that's due to the nature of the southern ECML (fairly flat part of the country, exposed) or the quality of the infrastructure

 

[petersi]

Hitchin and south the line was electrified late 1970s
North of Hitchin late 1980s

Sent from my Nexus 7 using Tapatalk

 

[rdeez]

The thing with the ECML is the widespread use of headspans (two metal poles with wires strung between them) means that when the wires do come down it's often much more significant than on the WCML which avoids their use entirely. With headspans when one line's wire come down it often brings down the others which isn't such an issue with cantilever or full gantry type supports.

When replacements happen are they still using headspans or using alternatives now?

 

[Trog]

The thing with the ECML is the widespread use of headspans (two metal poles with wires strung between them) means that when the wires do come down it's often much more significant than on the WCML which avoids their use entirely.

Not quite there is one headspan just north of Harrow, erected to replace a portal knocked down by a tube train.

 

[rdeez]

Just stumbled across this, easy to see how one incident can have lines out of action for so long!

http://www.youtube.com/watch?feature=player_embedded&v=XgCPPeYmyKw

 

[MK Tom]

Am I right in thinking the ECML was wired on the cheap? I've heard various things about Margaret Thatcher imposing economic requirements on BR, saying it had to pay for itself, about shallow mast foundations and the money saving decision to use wire in place of WCML-style gantries. As someone who lives on the WCML, I find it interesting that my local news is usually covering wire problem stories on the ECML. Usually far worse than anything that happens over here too - horror stories of trains stuck in the middle of nowhere for hours on end.

Personally every time I've used the ECML it's been running perfectly with everything on time. Which is never the case on the WCML. But then the WCML is a lot busier.

 

[Signal Head]

The thing with the ECML is the widespread use of headspans (two metal poles with wires strung between them) means that when the wires do come down it's often much more significant than on the WCML which avoids their use entirely.

That's true only for the original 1960s southern section. Headspans were used extensively, where there are more than two tracks, on the northern section of the WCML (ie north of Weaver Junction).

 

[boing_uk]

Preston being a particular example of headspans.

 

[Signal Head]

Am I right in thinking the ECML was wired on the cheap? I've heard various things about Margaret Thatcher imposing economic requirements on BR, saying it had to pay for itself, about shallow mast foundations and the money saving decision to use wire in place of WCML-style gantries.

As I recall, BR had to fund the ECML wiring out of its existing budget, there was basically little or no extra cash provided. This meant that some other projects were shelved in order to pay for it, and that economies had to be made. I understand one of these was to stretch the mast spacing out as far as possible, which makes the wires susceptible to greater lateral deflection under wind loading, and increases the risk of dewirement owing to the wire slipping off the edge of the pantograph.

 

[HSTEd]

And yet the ECML is a (for the most part) reliable electric railway that was delivered on a budget that wouldn't pay for the planning phases of a modern project, let alone the actual work.

 

[Signal Head]

And yet the ECML is a (for the most part) reliable electric railway that was delivered on a budget that wouldn't pay for the planning phases of a modern project, let alone the actual work.

Sadly true, I think the figure mentioned at the time was £306M, which would probably get you about 2.5 project managers today

 

[O L Leigh]

Funny. I seem to recall there being a big board outside York station saying that the electrification scheme had been (in part) financed by the EU Regional Development Fund, or somesuch. Is it no longer there...?

As to the disruption caused by dewirements, these are about equal between portal and headspan types. A dewirement almost always results in the blockage of all lines at the location due to either a) obstruction of lines due to debris, b) tripping the OLE supply, which leaves more than just the line directly affected without juice, or c) lines needing to be taken under possession in order to effect a repair.

Bi-mode or diesel services would not help, no matter what people might think. If the line is crawling with little orange men trying to pick up the pieces, shift the damaged train and put all the wiring back up where it should be, you can't run any sort of train through the section. It's best just to let them carry on and restore the power so that all services can be run.

Additionally, in defence of the headspan, it is a relatively simple job to repair one. This is partly due to it's lightweight construction, but also because it uses very few parts. Apart from the registration arms and the insulators, it's just cable, hangers and tensioners.

O L Leigh

 

[edwin_m]

Don't forget there have been quite a few WCML incidents recently too, but as the WCML probably gets a lot more electric traffic it's difficult to say which is more reliable.

The use of Eurostars on the ECML is thought by some to have damaged the OLE. Eurostar pantographs are primarily intended for use on high speed routes where the OLE is more robust and always stays at the same height,

 

[IKBrunel]

Just stumbled across this, easy to see how one incident can have lines out of action for so long!

http://www.youtube.com/watch?feature=player_embedded&v=XgCPPeYmyKw

Hmm... I suppose any form of pantograph brake or arc duration sensor which would drop the panto would be prone to false positives, But what about a cctv link to in-cab screen with an alarm activated by panto break or arc count/duration.
Evidently any panto failure device would need to be fibre optic based owing to need for 11kV isolation.

Shouldn't be super expensive to retrofit & would save a lot on OHLE repairs.

 

[noddingdonkey]

Bi-mode or diesel services would not help, no matter what people might think. If the line is crawling with little orange men trying to pick up the pieces, shift the damaged train and put all the wiring back up where it should be, you can't run any sort of train through the section. It's best just to let them carry on and restore the power so that all services can be run

Although it would, perhaps, open up more extensive diversion options, and allow a train wasn't involved in the incident that brought the wires down but is stuck behind it with no juice to set back bang road to a location where it can access a diversion or detrain the passengers without waiting for a diesel loco to rescue it.

 

[edwin_m]

Although it would, perhaps, open up more extensive diversion options, and allow a train wasn't involved in the incident that brought the wires down but is stuck behind it with no juice to set back bang road to a location where it can access a diversion or detrain the passengers without waiting for a diesel loco to rescue it.

Even the "electric only" IEPs will have a diesel engine which is capable of moving it slowly for a few miles. This plus bi-mode could also mean there is the option of just clearing up the mess and making everything safe, then resuming service until a convenient time to bring in the wiring train. While I hesitate to differ with Roger Ford and other luminaries (not least those on here), the idea of the IEP "donkey* engine" is starting to grow on me.

*Not a noddingdonkey engine!

 

[tbtc]

Bi-mode or diesel services would not help, no matter what people might think. If the line is crawling with little orange men trying to pick up the pieces, shift the damaged train and put all the wiring back up where it should be, you can't run any sort of train through the section. It's best just to let them carry on and restore the power so that all services can be run

At least with bi-mode you could move a stuck train back out of an affected area, to the nearest station (rather than being stuck for hours) - even if you can't move through an affected area to get to the far side.

 

[O L Leigh]

Although it would, perhaps, open up more extensive diversion options, and allow a train wasn't involved in the incident that brought the wires down but is stuck behind it with no juice to set back bang road to a location where it can access a diversion or detrain the passengers without waiting for a diesel loco to rescue it.

Not so.

The restriction on diversions will have more to do with route knowledge of the crews and available slots on the diversionary routes themselves than the capabilities of the train itself. Besides, the rules already exist to permit electric trains to coast through an affected area with the pan lowered. By the time the decision has been made to set trains back "bang road", as you so quaintly put it, there is a good chance the affected area will have been shortened by using sub-section switches restoring power to parts of the affected section.

The benefit of bi-mode or diesel traction under these circumstances is small.

O L Leigh