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Old 21st December 2017, 09:14
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Beeyar Wunby Beeyar Wunby is offline  
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Join Date: Dec 2012
Location: NW Norfolk
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Quote:
Originally Posted by justin View Post
I'm trying to research how common on-board sanders are, but haven't found much stats or regulations. Anyone knows if there are any regulations/standards that require them? Or if there isn't any, how common are they?
Google is your friend: Link here....Railway Group Standard RT2461: Sanding Equipment Fitted to Multiple Units and On-Track Machines

In the UK, almost all traction units (ie, locos and multiple units) have sanders. Our 'green and pleasant land' means that stopping and pulling away in the leaf-fall season can be extremely tricky on occasions. A steel wheel on a steel rail, with a layer of vegetable oil in between means that there can be little or no adhesion sometimes.

Modern units may have a combination of;
1) Autosanders which lay fine sand under the powered wheels whenever the Wheel Slip/Slide Protection system detects that the train is struggling, and
2) A Manual sanding button which allows the driver to lay sand even though the train doesn't think there's a problem (if all the wheels are locked, the WSP system may think the train has stopped !), or increase the rate of sanding if the autosander is already deployed. This button is also known affectionately as the 'brown trouser' or 'sphincter' button. I'm sure you can work out why.

Additionally there are automatic sandite applicators at various points on the line where there is an area of known low adhesion, and the RHTT (Rail Head Treatment Train) runs across the network using a high pressure jet of water to clean the railhead.

As aussiesteve points out above, drivers are required not to lay sand over points or crossings because it can bung them up, and there is a risk that the build-up of sand may isolate a train from the track circuits and make the train disappear from the signalling system !

However if your train is running away, and they do, you will chuck every grain of sand down regardless.

HTH, BW
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