Sand & traction when climbing up a 2% grade?

Question

My question is this: When a locomotive is pulling a train at run 8 up a 2-3% grade. Does the engineer aply sand from the starting point all the way up to the summit of the hill? Does the lead unit aply only the sand or does all the trailing units aply the same amout of sand to pervent whell slip?

Answer 1

All units supply sand.

Sander controls are no longer able to be left running.  They will apply sanding automatically as needed.  The manual control is now a button that needs to be depressed and held in to apply sand.  At one time there were valves that could be left open.  Also, in the past, some engineers would sand heavily, which is a no-no when operating over switches.  Over time, the sand will build up between the switch points and require increased maintenance and/or keep the switch from operating properly.

But, sand isn't always employed for traction on moving trains.  It is recommended that when stopping on heavy grade, where there may be traction issues involved to get the tonnage started again, sand should be applied to the rail when stopping, for at least the length of the locomotive consist so that it is already under the locomotive wheels before attempting to start again.

Older units also had the ability to apply sand to the lead truck only, usually via a toggle switch, which is the truck most susceptible to slipping or excessive wheel creep.

In addition, when sanding rail for better adhesion, if excessive, you will also be increasing the drag generated by the wheels of those cars immediately behind the consist.

Answer 2

Traction control has gotten so good on the new engines because of micro processors that they do most of the decision whether to sand or not.When they do sand it's the whole consist.Most of the new engines make you hold down the button to get sand and still don't work if your above 20 mph.Sand is most critical when you get down to very low speed with a high tonnage train.One good slip and jerk(especially on wet rail) can pop a knuckle usually in the first ten cars from the engines.So if i'm going to manually sand i do it at when i get down to 10 mph and on the lead axle.If it's pouring rain or a blizzard i'll sand the whole consist.Rango or someone else here might have some better thoughts on this as he runs 2% stuff.My run doesn't have anything that steep.I'm more of a 1% kind of guy lol.

Answer 3

Andy has it right, the automatic sanders do the job most of the time, far far better than locomotives of even 10 years ago. The problem is, no matter how good they are, automatic sanders by their nature only work after you start slipping.

(the railroad term for wheels turning faster than forward speed or "spinning" as it is known in automotive terms)

At slow speed almost all engineers apply sand, especially on curves or places where it is known you will have trouble.

There is the option of all sand where each forward facing powered axle in the consist gets sand, (well, that's the theory at least) or the leading axle sanders which do exactly as the name suggests.

On straight dry rail at speeds above 12 or 14 MPH I dont usually use sand, we've all been in situations where we used all our sand where we didnt really need it and then ran out before we got to the really bad stuff. Most engineers use as much as we feel necessary but not more, you never really know how much you have left.

It really doesnt make any difference whether the grade is 2% or .2%, if you have maximum tonnage for your locomotive consist, you need sand, especially on slippery or wet rail.

Answer 4

As stated above.  I pretty much have the new evolution series engines and although they have sand buttons or switches on them...........they don't work.  The engines' computer detects the slip and sands when it's ready.  I was just complaining about that a few days ago.  Why have the buttons if it wont let you use it?  It's all really set up for failure.  Sand only works when you start slipping usually at lower speeds........and when it finally does kick in........it's to late.  Where's the logic?