Sand boxes on locos.

[centenary]

OK, all \ most locos have sand boxes so they can drop sand on the rail when they get wheel slip. Ive seen kettles use a lot of steam to squirt the sand onto rails, diesel electric use compressed air?

When you use compressed air, you get water vapour so how come the sanders dont get blocked with a mixture of 'wet' sand?

[Richard08]

All you ever wanted to know about 'modern' sanding... (Sheffield University paper)

https://eprints.whiterose.ac.uk/110459/ ... 201%20.pdf

[Bigmet]

...When you use compressed air, you get water vapour so how come the sanders dont get blocked with a mixture of 'wet' sand?

There are well established techniques for drying compressed air. All the industrial plant using compressed air that I have had anything to do with required the compressed air to be 'dry', often to a demanding specification requiring regular monitoring as part of the process control system.

[centenary]

Fascinating! Thanks both.