Couplings - How did they make them?

I think we're getting into semantics here. Most people, me included, would consider the load of a train to be it's mass. Plainly the force required to pull it along is a lot less than that reguired to lift it. VE did state The load is the same on the hook wether you are pulling the load or lifting the load which is the source of the confusion

1000 tons would be a heavy train in the UK and I suspect most of Europe. The monster trains in USA, Australia etc sometimes have locos distributed along the length, not only pulling and pushing, and I very much doubt they use chain couplings, but I'm open to correction.

Looked up the article on making hooks and chains, chains were made by flash butt welding from 0.2% carbon steel (pretty much EN3 territory) and then load tested at 75 tons. Hooks were forged from 0.3/0.35% carbon steel, getting up towards EN8, but not tool steel.

Edited By duncan webster on 13/06/2018 10:08:16

I think Isaac Newton (or Scotty) would say you cannot change the laws of physics. Third law - to every action there is an equal and opposite reaction.

No matter the mass of the train, the constant load on the chain cannot exceed the mass of the locomotive, multiplied by the coefficient of friction between loco and the rails, which is normally less than one (unless it is a rack loco) and probably about 0.4.

There is one exception - shock loads, but because the free play between loco and lead carriage is pretty small, this can't reach high values.

Neil

P.S. how do you flash butt weld a chain link - surely it's shorted out on the other side of the link?

I'll answer my own question... 'like this' - the other side gets very hot, but it works!

the waggon chains were 2 U shapes welded together all in one operation. It obviously worked, they made gazillions

Here's another video of chain making, all the way from wire to finished chain, and not a chainsmith in sight

**LINK**

We only have toy trains in the UK then!

Yes, but if you get stopped at a level crossing in USA you might as well have a nap, or get a book out, it takes forever for them to pass as they are very long and quite slow, they don't have to keep up with passenger trains because there aren't many.