Third rail in the snow

[Mojo]

The recent snow[1] again caused mass disruption on the Southeastern network, particularly on Sunday. The problems mainly seemed to be attributed by the Toc as caused by issues with the conductor rail.

Do Tocs operating over third rail (or Network Rail) operate overnight sleet trains, and how many of their trains have sleet brushes and/or trains capable of spreading de-icing equipment?

[1] Saying that, I never saw any snow so don't know what the fuss is about, but I can't be everywhere

 

[wibble]

The recent snow[1] again caused mass disruption on the Southeastern network, particularly on Sunday. The problems mainly seemed to be attributed by the Toc as caused by issues with the conductor rail.

Do Tocs operating over third rail (or Network Rail) operate overnight sleet trains, and how many of their trains have sleet brushes and/or trains capable of spreading de-icing equipment?

[1] Saying that, I never saw any snow so don't know what the fuss is about, but I can't be everywhere

It's not just snow, it's ice as well and was the cause of delays on SWT on Tue 18 March. I don't think passenger trains are fitted with 'sleet brushes' but Network Rail do operate de-icing trains which spray de-icer onto the conductor rails and/or tracks.

 

[pendolino]

All sorts of measures are in place: heated 3rd rail, NR running MPVs to lay de-icing fluid, ghost trains, software modifications & Ice Mode on 377s to reduce sensitivity to power surges, and I read something about a couple of 377s being fitted with equipment to lay de-icing fluid.

Doesn't always work unfortunately. It's not snow as such, more to do with a layer of ice building up on the 3rd rail preventing the train drawing power.

 

[tsr]

There are a number of "snow trains", as well as Railhead Treatment Trains (RHTTs), which are glorified MPVs fitted with de-icing equipment. The snow trains have ploughs at each end attached to two locomotives (as well as the de-icing system, I believe). RHTTs either operate in their own paths, which are often clear for them year-round, or under VSTP schedules (if more are needed in very severe conditions). The deicer fluid is regularly heated. These trains still cannot always resolve ice on the third rail, which in extreme cases has needed to be cleared manually (yes, really). Despite the aforementioned new power management software and WSP on 377s, these trains and others still can't always pick up enough of the traction current (pardon my brain malfunction which means I may not use correct terminology!). In December 2010, I was on a train with experimental power management software, but despite this, I was still able to coax an improvement by turning off all the interior reading lights (these had somehow all been erroneously left on!).

Around late autumn, it can be tricky for NR to decide whether or not their RHTTs will be in leaf clearance or ice clearance mode. The lack of suitably equipped MPVs at Tonbridge led to delays at least once this winter.

 

[pendolino]

In December 2010, I was on a train with experimental power management software, but despite this, I was still able to coax an improvement by turning off all the interior reading lights (these had somehow all been erroneously left on!)

In what capacity were you on this train then? Driver? Fleet technician?

 

[tsr]

In what capacity were you on this train then? Driver? Fleet technician?

I was just a regular passenger. I helped the guard do it manually - each switch to off. It worked. The rest of the lights stopped working. Quite why nobody could just break the circuit/flick a master switch, I don't know. Also, I don't know who turned them all on. I think it was a special timetable service just after 2000 from London Victoria around the time of the second bout of heavy snow (20 December 2010 or so?).

 

[pendolino]

I was just a regular passenger. I helped the guard do it manually - each switch to off. It worked. The rest of the lights stopped working. Quite why nobody could just break the circuit/flick a master switch, I don't know. Also, I don't know who turned them all on. I think it was a special timetable service just after 2000 from London Victoria around the time of the second bout of heavy snow (20 December 2010 or so?).

Reading lights can be switched on/off (to test them) via MITRAC from the driving cab, and to the best of my knowledge it's not something that fleet have ever suggested we try when experiencing traction current problems so you'll have to excuse me if I say I think your story is a little far fetched. But who knows, stranger things have happened.

 

[tsr]

Reading lights can be switched on/off (to test them) via MITRAC from the driving cab, and to the best of my knowledge it's not something that fleet have ever suggested we try when experiencing traction current problems so you'll have to excuse me if I say I think your story is a little far fetched. But who knows, stranger things have happened.

Can it be done from MITRAC? I thought it might be able to do that. Hence why sometimes they reset themselves before the train sets off.

It is a weird story. I appreciate it seems far fetched. But it happened! Evidently it was a bit of a last resort. The train was really struggling and (aside from the actual rails themselves, where ice was more of a problem) there was about 30cm of snow in places. A local weather station recorded -17ºC or so in a sheltered part of the locality that evening (Redhill/Reigate area). Leaving all those lights on can't have done any good, that's for sure.

 

[Southern313]

I believe there is also MCB for reading lights in every body end cupboard.

 

[tsr]

I believe there is also MCB for reading lights in every body end cupboard.

Should each and every guard be aware of this, just out of interest (if you know)?

 

[SPADTrap]

This is what happens when trains hit an icicle which shorts out the OHLE. Caught this at Watton-At-Stone earlier..

http://www.flickr.com/photos/samcooper317340/8593352672/in/photostream

 

[Bald Rick]

It is ice that is the problem for con rail, not snow.

On Saturday night we had almost the whole fleet of winter treatment trains out treating. Unfortunately it rained in the early hours and washed the anti-ice away, and then that same rain froze. Also being Sunday morning, some routes were blocked for essential maintenance works, and these routes were not treated.

The con rail heating worked a treat. But it is not fitted in the SE metro area as a) the intensity of service keeps the con rail clear and b) it is usually warmer. That is except on very cold Sunday mornings. However it is now in the programme to be fitted.

No trains on the NR network have sleet brushes, as they wear out quickly and don't work too well above 40mph. Good for LU, not good for us. A number of the 375s have in-service anti icing kit fitted, but this is to keep the services going, and not that effective at start up.

So a bit of a sorry story.

 

[Mojo]

Thanks Rick, good to hear, let's hope some lessons are learned and improvements made. It's beginning to get to a point where I'm a bit reluctant to rely on the service in the poor weather but have no problems relying on the alternative service on the Underground who run sleet trains all night long on many nights where rail ice is forecast. Typically problems on the Underground during the poor weather tend to be with frozen trainstops and snow compacting in the points, rather than electrical issues.

 

[ChiefPlanner]

Some of us used to run 6 car 313's all night Harrow to Watford , with de-icer sprayed on the shoes (the Bakerloo used to cover Kilburn - Harrow all night with de-icer fitted 72 TS) + same on the NLL 3d rail (when it existed) + all berthed stock from Camden to Northampton had the door's manually sprayed with de-icer , and stabled units left "cut in" with all heaters on.

Still had problems though ........

 

[HSTEd]

This probably sounds absurd.... but what about putting the tracks inside polytunnel like structures?

 

[tsr]

This probably sounds absurd.... but what about putting the tracks inside polytunnel like structures?

Well...

Wind. Weight of the snow on the tunnels. Problems finding a good way to put them up. Gauging/clearance. Stations. Wide track layouts.

A good idea for some static industries (e.g. some horticulture/farming). Not good for fast-moving transport services with tricky infrastructure to negotiate!

 

[Mojo]

Is it also something to do with modern trains being less likely to "play ball" with ice when it comes to drawing power?

 

[Bald Rick]

Is it also something to do with modern trains being less likely to "play ball" with ice when it comes to drawing power?

There are numerous stories of spare drivers / guards physically holding the breakers in on EPBs / VEPs etc as they drew far too much current for their traction motors in the ice. Which wasn't necessarily good for the equipment or the well being of those doing the holding. Also various stories of the power equipment melting. Modern trains have protection to stop this happening, indeed 'ice mode' on the electrostars simply weakens the protection for the few hours/days it is needed.

As for poly-tunnels, a better way would be to replace the con-rail with OLE, but we're not doing that anywhere. Oh hang on....

 

[Chrisgr31]

I think the conductor rail on the East Grinstead line may of been heated, certainly as far as Oxted, because the electrics havent been holding up the diesels this winter.

There has been a dramatic improvement in reliability this year on that bit of reliability.

 

[merlodlliw]

In the old days of BR they used to run what were called "Ghost Trains" all night.

I recall the term used by BR staff when I was involved in News Trains.


Bob

 

[Mintona]

We still run ghost trains! When it's expected to be really cold or snowy you'll often find empty trains quizzing around all night.

I must say, I think Network Rail have done very well this year. Large sections of heated conductor rail, and almost all points seen to be heated now as well, and I've also seen lots of de-icing trains. In addition, the 375/8s(01-20) have all been laying gel on the conductor rail as well. It's meant the problems have been much less than in previous years.

Of course, there's always more that can be done.

 

[ChiefPlanner]

We still run ghost trains! When it's expected to be really cold or snowy you'll often find empty trains quizzing around all night.

I must say, I think Network Rail have done very well this year. Large sections of heated conductor rail, and almost all points seen to be heated now as well, and I've also seen lots of de-icing trains. In addition, the 375/8s(01-20) have all been laying gel on the conductor rail as well. It's meant the problems have been much less than in previous years.

Of course, there's always more that can be done.

Put it this way - Scotrail did 94% punctuality yesterday - many other operators did very well too - where there were no infrastructure problems or incidents. Somehow the media does not pick up the good work out there in freezing conditions.

Only bit of the system still blocked at 0600 today was the Hindlow line north of Buxton ( big drifts - probably cleared by now)

 

[Manchester77]

Could (and this is a stab in the dark and unrealistic)
You raise the current so high just before trains are due to run that it melts the snow? How high would that be I'm thinking at least 3000vDC

 

[Bald Rick]

Could (and this is a stab in the dark and unrealistic)
You raise the current so high just before trains are due to run that it melts the snow? How high would that be I'm thinking at least 3000vDC

You could, but it would necessitate replacing all the distribution equipment, plus all the signalling out on the ground, and it wouldn't work. 25kv doesn't melt the ice on OLE (although this isn't strictly relevant).

 

[apk55]

I would think the problem would be thaw freeze cycles. If the conductor rail is just above freezing then snow would partly melt, then as the rail dropped below freezing it would refreeze and form hard ice that would form an insulating layer on the rail. Very cold weather is probably less of a problem as snow would not stick, and just brush off. Traction current woud heat the rail by a few degrees although the effects would be varible along a section. If the ambient is just below freezing this could cause ideal conditions for thaw freeze cycles.
Our climate is good for freeze thaw cycles , this is why our roads suffer badly in winter even compared to countries that have much colder winters.

 

[jopsuk]

Could (and this is a stab in the dark and unrealistic)
You raise the current so high just before trains are due to run that it melts the snow? How high would that be I'm thinking at least 3000vDC

you only get a current when the circuit is completed (ignoring leakage loss due to poor insulation). Without a train in section, you get no current. Voltage is the measure of Potential Difference- not current. You can have very high currents from very low voltages, and vice versa- in fact, this is the basis of transmitting electricity at high voltage, as the resistive loss is lower with high voltage/low current, but for use in devices higher currents and lower voltages work better.

 

[Skoodle]

On the East London Line, we have night turn drivers run deicing units when they can. There's about 10 units with deicing equipment installed on them. They run whilst in service too.

We also have ICE mode which we have to use when conditions require. Not sure exactly what it does, someone else may be able to clarify, but I believe it's something along the lines of stopping the traction packs dropping out through not being able to draw current.

 

[notadriver]

ICE mode makes the line interference monitors or LIMS less sensitive to electricity arcs caused when the collector shoes come into contact with the icy conductor rail.