• Railyard operations

  • General discussion about railroad operations, related facilities, maps, and other resources.
General discussion about railroad operations, related facilities, maps, and other resources.

Moderator: Robert Paniagua

  by JL2091

I am new to railways and railway operations and was hoping I could get some answers about how hump railyards operate.
According to my research, hump railyards use (pneumatic?) retarders after a railcar is pushed over a hump to reduce the speed (gravity does the rest), and also that the brakes on the individual railcars are disengaged during this process.

My question is (if the above is correct), what if the railcar somehow clears the retarders and doesn't slow? Is there another failsafe that prevents accidents? Additionally, how often do damages occur in such a yard - I read on a different forum that sometimes they just let the cars crash into each other? Surely that's not right!
I would imagine the operators and the computers should be reasonably accurate most of the time.

Many thanks for any responses.
  by ExCon90
The hump isn't there to slow the cars down; the cars have ben standing in the receiving yard since they arrived, waiting their turn to go over the hump, which is there to provide a downward slope for each car after it is uncoupled at the crest of he hump.

During classification the cars are without brakes, having been drained of air after arrival; the retarders slow them down as necessary (nowadays the system factors in the track curvature of the route the car will take, which way the wind is blowing and how hard, etc.). I don't know how a car might avoid the retarders, but to earn its keep a hump yard needs to classify thousands of cars every day, around the clock, so it doesn't seem to happen very often. Occasionally the computer gets it wrong and you have what's called a "rough coupling," and the claims department will be hearing from the shipper.

It's always good to hear from someone interested in railways; anything you want to know, this site is a good place to search.