noun
Meaning 1
A device that retains some air pressure in a train's air brake cylinders even when the automatic brake valve is set to the fully-released position, used on steep downgrades to allow a degree of continuous braking effort to be maintained without depleting the pressure in the train's brakepipe (which would result in the loss of nearly all braking ability, causing a runaway).
Definition source: English Wiktionary via Wiktextract
Topics: engineering, mechanical, mechanical-engineering, natural-sciences, physical-sciences, rail-transport, railways, transport
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided