Railroad track cooling in Italy
Ever wondered why the tracks of the railroads in Italy?
are painted in white? One might guess it’s for anti-rust,
others might think of better visibility for trespassers.
But the reason is much more simple and also clever…
As we all know, dark colors absorb the light of the sun and convert it to heat. So is black allowing a massive heat-up from the sun especially in summer.
White however is reflecting light very well and thus affects heating in a positive aspect. You will most likely swelter to death in a black car while sitting in a white car is a breeze compared to the black car.
And it’s the same for the railroad tracks:
the rusted color (mostly bright to dark brown according to the particles that are bound in the rust tend to absorb a lot of th sun’s heat and thus warm the tracks up to 60 degrees. Since steel tends to expand when heated, the train committee in Italy decided to paint the tracks in white:
The result is impressive: A white-painted track segment is 7 degrees cooler than a normal track segment and reduces the expansion by 3cm every 200m. Since 5cm difference may lead to closure of the track as the railway beams might lift, bend or break, this is an innovative way to keep the tracks “in shape” and allow the trains run longer even with searing heat outside.
Clever idea!
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