Newby question of the day “why do diesels take on sand?”
It is not so much because they are diesel engines, but it has everything to do with wheel spin.
Even though engines are heavy, wheel spin can occur when a train starts to move etc., certainly when the rails are wet (read slippery).
By dumping sand in front of the wheel, you can attempt to avoid wheel spin, and get the train to move.
You don’t want to use it to stop wheel spin, you want to use it to avoid it. It is not a good thing to dump sand when the wheels are spinning, you want to use it when you know they will spin, but you need to dump it before the spin start.
Hope that answers your question.
It also helps in braking.
In the locomotive there is a wheel slip indicator that will either blink or come on and buzz when your wheels are slipping. If the wheels are slipping you should turn the sander on. This way the sand will give traction and yes it will help to prevent wheel slip.
Alos when you throw the Automatic(train brake) into the emergency application the sand will come on automatically to help the wheels from slipping on the rail. The rails are greased to prevent wear on the wheels while the train takes corners. Plus it doesn’t create as much friction as it would on a none greased rail.
James
Every diesel from the first GE test units in 1918 on has needed sand for all the reasons shown above and (I presume) below. Sand capacity was an issue with some models over the years, while positioning of the sand fills has been a problem espically up in the frozen north! (melting snow or ice finding its way into sand boxes, in defiance of designer’s attempts to prevent this from happening.)
we use sand for traction on slippy rail… if the wheels slip…you put it down to grip… so when the sand box gets low…they need to put fresh sand in it so you have it if you should need it
csx engineer