Common Wheel Arrangements on Mountain Railroads?

[BigBoyFan4006]

What non-geared steam locomotive wheel arrangements where common on mountainous narrow gauge railroads? Or in other words, good/great at climing steep grades and having the ability to negotiate tight turns, while also being able to haul a good size load for the size of the locomotive.

 

[watemple]

I suppose the Heisler. That is the only one I can think of.

 

[BigBoyFan4006]

I suppose the Heisler. That is the only one I can think of.

Heislers are actually geared. But thanks for trying to help!

 

[rbar_164]

One would imagine mountain types would be ideal for such lines, ie. 4-8-2s. From what I can gather, railway companies would want something well balanced and easy on curves, so something with both front and rear pony bogies. As such, on the narrow gauge railways here in Victoria they adopted Baldwin built prairie 2-6-2 Tank engines, perfectly balanced with the water tanks above the driving wheels, capable of navigating tight curves on steep hills in forward and reverse. They also employed a pair of 2-6-0-0-6-2 garratt locomotives, though I've heard the South African NGG16 garratts would be more suitable to the curves, the inside pony wheels of the 2-6-2-2-6-2 arrangement being easier on the track.
In the US I believe they often went for mountain or Mikado types, maybe a consolidation here and there. Though keep in mind, before building the K27 locomotives the D&RGW would need up to 4 C16 or C19 locos to haul 4 loaded gondolas up a 1 in 30 grade, so something beefy may be more up your street.

Cheers
Stevo

 

[BigBoyFan4006]

So a 2-4-2ST would be more preferred than a 0-4-2ST. Gotcha.

 

[kws4000]

What non-geared steam locomotive wheel arrangements where common on mountainous narrow gauge railroads? Or in other words, good/great at climing steep grades and having the ability to negotiate tight turns, while also being able to haul a good size load for the size of the locomotive.

Believe it or not, but the D&RGW narrow guage did at one point have plans for 4-8-2 and 2-8-8-2 on the books, but nothing ever came of them. I'd find it if I could, but I believe it was somewhere on the Trains Magazine forums. TBH, American NG never went bigger than 2-8-2, either East or West. In the UK, a Fairlie 0-4-4-0 was standard, except where they didn't, in which case they used 0-4-0T or 0-4-2T. Africa, pretty much anything went.

 

[BigBoyFan4006]

It would make since that narrow gauge steam never got much bigger than 2-8-2's, seeing as how the locomotives would have to have a small enough wheelbase to negotiate the tight turns, the loads weren't normally large enough to warrent anything larger than a 2-8-2, and the locomotives needed to fit in a smaller-ish loading gauge. There were, however, 4-8-4's used by South African Railways, but the SAR had a 42 inch gauge, and it never encountered any major grades (so you could say it doesn't count).