Tell me crucial things about railway coupling... mainly s***w coupler?

Question

Tell me crucial things about railway coupling... mainly s***w coupler?

Answer 1

ahem . . . .. .

I try to "couple up" every chance I get.

it's not crucial but it is a good thing.  

Answer 2

Have a look at this, it explains it a lot better than I can:

http://en.wikipedia.org/wiki/Coupling_(r...

Answer 3

s***w couplings are not that common these days, having been superseded on British railways by buckeye couplers on freights and a variety of other types on passenger stock.

s***w couplings consist of a central threaded barrel with a "D" shaped adjustable end which fits over the coupling hook of an adjacent vehicle. In the centre of the barrel is a handle to turn the s***w.

The correct way to couple using a s***w coupling is to have equal amounts of the barrel either side of the handle. This is acheived by adjusting the "D" end so it's the same distance from the central handle as the fixed end. Once the "D" end is coupled to the adjacent vehicle, the central handle is used to turn the s***w, thus shortening the coupling, until the adjacent vehicle's buffers are just touching the vehicle it's being coupled to. This ensures that the coupling is tight enough to prevent a "snatch", i.e. too hard a sudden pull by the locomotive, yet not too tight to cause a derailment by having the vehicles locking buffers on tight curves.