A heavy steel chain attached to the end sill of a railcar, positioned on either side of the center drawgear. These chains act as a secondary connection between cars, designed to keep the train together if the main coupler fails. They were standard equipment on early passenger and freight equipment before the widespread adoption of fail-safe automatic couplers.
Heard on the job
Make sure the side chain is hooked up before we move that museum piece out of the shop.
Insider tip
You will mostly see these on historic rolling stock or specialized maintenance equipment where standard knuckle couplers are not trusted on their own.
Also heard as
- safety chain