Point rails panited white.

[Joseph_Locke]

... and if you want to be exact, the thermal expansion of switch rails (which are by definition always fixed at one end) can be (relatively) significant on long switches ( I make it 24mm on a 40m switch rail over normal extremes of UK rail temperature) - this is a small issue of switch toe and POE misalignment in a turnout, but a massive problem in a switch diamond (readers may care to take a moment to draw a diagram).

Anything you can do to reduce the movement of the switch rails relative to the knuckle is a good thing - if reducing the thermal variation of the switch rail by 5 degrees is all you achieve by painting the rails white then all to the good - any reduction is an improvement.

The actual benefit will depend on the local topography and the alignment of the rail webs - webs that face south and which are located in a shallow east-west cutting will experience maximum solar gain and should be prioritised.

 

[66Yorks]

Taken directly from Network Rail website:

'We paint the rails white at critical points so they absorb less heat, reducing expansion; typically a painted rail is 5 to 10 degrees centigrade cooler than an unpainted rail.'

 

[najaB]

With such a comprehensive refudiation of tim_lathe's opinion there's only one thing that can be said...
[youtube]jaRBHQlEu-o[/youtube]

 

[Deepgreen]

With such a comprehensive refudiation of tim_lathe's opinion there's only one thing that can be said...
[youtube]jaRBHQlEu-o[/youtube]

Given the OP's surname, perhaps you could be said to have worn him down.

 

[AM9]

Given the OP's surname, perhaps you could be said to have worn him down.

... and parted off.

 

[D Foster]

Okay, so accepting that the elements of S&C are painted white to reduce the build up of heat - and not just to provide opportunity for the P Way to decorate their feet and legs...
Why have I seen the rails through some level crossings (mainly those fitted with Bomacs) painted white - fading rapidly to crud-colour? This is on both sides of the web and foot. (Umm... It becomes visible all the way through the crossing when the Bomacs are lifted out for any reason - and usually extends a metre or so either side of them).

Thanks
--- old post above --- --- new post below ---
UK rail in plain track doesn't usually buckle much when it gets too hot - but it can still buckle enough to derail a train. I've seen pics from around the world of track that has massively distorted right out of the ballast.
There used to be special heat patrols in very hot weather.
Also, some problem locations had a short length of rail (about 80cm I think) set up close to the track with a thermometer in a slot cut in the head of the rail under a thin (protecting) metal lid. Somewhere I have pics of some of these that had been taken out in the Warrington area.

 

[455driver]

Why have I seen the rails through some level crossings (mainly those fitted with Bomacs) painted white - fading rapidly to crud-colour? This is on both sides of the web and foot. (Umm... It becomes visible all the way through the crossing when the Bomacs are lifted out for any reason - and usually extends a metre or so either side of them).

Thanks

I think its because the rail through level crossings can be made of different steel to stop road salt eating it away.

 

[Darbs]

Yes, treated rails and fastenings for level crossings and tunnels if there's risk of high rates of corrosion. Or they used to get us to to brush it on by hand!

 

[Ploughman]

Clips for use in high corrosion areas used to be Sheradised.
https://en.wikipedia.org/wiki/Sherardising

In the open rails can last for decades but in some areas rail has been known to have to be changed within 2 years due to corrosion.
Tunnels and Chemical attack usually the worst causes.
Wet tunnels such as Bramhope on the Harrogate line, for one example, used to have severe corrosion of the rails under the blind shafts.
Since then roof drainage systems seem to have improved the situation.

 

[Trog]

The rails through level crossings are not a different type of steel, but in many crossings normal rails are used that have been coated with a special protective paint layer which is usually a cream to pale magnolia colour, or rails with a sprayed on aluminium coating. This is to help protect the rails from corrosion caused by road salt. You sometimes see odd coated rails used away from level crossings, where a bit of rail was needed in a hurry and a coated one was all that was available.

 

[civ-eng-jim]

One of Network Rail's "Standard Tasks" videos on painting rails.

https://www.youtube.com/watch?v=8Pk0ZxxDaxo&index=11&list=PL4QV024lDAiWPcQT-IHNaZLX4MMRcLj-t

 

[edwin_m]

And a RAIB report just released on an accident where failing to re-paint the track was a possible factor. Includes quite a lot of interesting information about rail buckling.

https://www.gov.uk/government/news/report-112016-freight-train-derailment-near-langworth