Shay Some Light on this will you?

[SuperSpeedMaglev]

The thing I don't get about US Shays, why is one side like cogs and the other wheels?


SHAY some light on this will you?(puns)

 

[cascaderailroad]

The pistons are all on the one side ... and nothing on the other side

 

[SuperSpeedMaglev]

Not helpful, but umm...thanks?

 

[edh6]

Because you only need the gearing on the one side, unlike coupling rods which need to be on both sides to function correctly.
Thus the gearing is on just one side, which is the same side as the cylinders.

The cylinders are mounted next to the boiler on one side of the running plate, whilst the boiler itself is offset to the other side such that the whole thing balances out.

 

[edh6]

An additional query from me: Where shays simple expansion engines, or compounds? I ask because the array of cylinders mounted alongside the boiler reminds me of a triple expansion marine engine.

 

[bendorsey]

I'd think simple engines since making them as triple expansions engines would generate some definite engineering problems.

From what 've seen of compound engines the LP cylinders are usually twice the diameter of the HP ones. Stroke must of course remain the same. On a shay that would cause the boiler to be further offset and possibly reduced in diameter or would need the cylinders moved outward towards the side making the engine wider.

And that's for a two stage engine Three stages and more make the problem worse.

There might be a solution but I've never seen or heard of it. Instead of putting the cylinders on one side of the boiler - place them underneath. The gear train would still be in the same place but cylinder diameter would not be a problem.

Told ya I was crazy, lol.

Ben

 

[JIb228]

Both sides are wheels. One side has gears, cogs as you call them, to link drive shafts to the pistons. Much like what the read axle of a rear wheel drive car looks like.