COUPLER POSITIONS
COUPLER EXTENSION:
Movement of two couplers in opposite outer direction is called coupler extension. ( This happens during run out)
COUPLER COMPRESSION
Movement of two couplers in opposite inner direction is called coupler compression. (This happens during run in)
COUPLER FORCES
DRAFT FORCE :
Force required for pulling other attached coupler / wagon is called draft force. Pulling of the other wagon starts only after complete extension of the couplers attached together.
BUFF FORCE : Force required for pushing other attached coupler / wagon is called buff force. Pushing of the other wagon starts only after complete compression of couplers attached together
