Are american couplers more efficient than European couplers?

[TheOofertaffy]

^
Pros and cons of both?

[Jack.Grave]

Tough question. In short yes and no. Because here in Europe is faily big number of various couplers used from bog standart screw-link and buffers, several variants of Schafenberg/Dellner coupler (automatic coupler mainly use on EMU/DMU units with internal wiring and piping), some countries uses "russian" Willison coupler. some stock uses modified ARR coupler (drop head buckeye).
If we took in sight just ordinary screw-link and buffers vs ARR. I thing its 50/50 because all have its pros and cons and its dependant of best railway practice in any given country. Maybe ARR is a wee bit better but is ugly. Jack

[cuavas]

Janney couplers[en.wikipedia.org] (common in America, Australia and China, particularly for freight trains) have a number of advantages over buffer and chain couplers[en.wikipedia.org]:

• Can handle higher loads, hence longer/heavier trains (up to 32,000 tonnes vs about 4,000 tonnes).
  
• Quicker and easier to couple and uncouple.
  
• Immune to buffer-locking.

Europe is slowly switching freight over to a variant of the Russian SA3 coupler[en.wikipedia.org] with added air and electrical connections, known as C-AKv[en.wikipedia.org]. It has many of the same advantages as the Janney coupler.

Passenger multiple units usually use fully automatic couplers (SchaKu[en.wikipedia.org] variants are probably most common). These have the advantage of being able to couple and uncouple trains without leaving the cab. They can’t handle as much load as Janney couplers, but in a multiple unit, power and braking is distributed along the length of the train, so the load on the couplers isn’t very high.

[electronx]

Not just easier but safer to operate: no need to lift the chain and then screw them together, while standing between the buffers - you might get run over.

It's also more push friendly (you can tighthen chains very much, too - usually done for passenger equipment, but in bends the push is on the inside buffer) - several people from the UK have gone lengths explaining how a train is never bunched, i.e. never pushed.

Due to being more powerful, US railroads overwork them and in practice break a lot of couplers, possibly more than chains. As in, I never heard about European train breaks (they exist occasionally), as opposed to daily in the US. Also, while they might work on straight track, extreme loads can cause consist tilt in bends and thus it's DPU operations anyway. (A typical European electric has the same effort as two typical US diesels: over 8000 horses. Resulting in more rapid acceleration.)

[edward.martin59]

The USA trains carry an 80 pound knuckle for broken couplers which can be replaced by the conductor in 20 minutes. Not that common an incident but does happen.