downcomer

About 0.06 uses per million words.

Meaning

1. noun A pipe to conduct something downwards. A large external pipe in a water-tube boiler, carrying unheated water from the steam drum down to the water drum as part of the circulation path. A pipe for leading the hot gases from the top of a blast furnace downward to the regenerators, boilers, etc.
2. noun A large external pipe in a water-tube boiler, carrying unheated water from the steam drum down to the water drum as part of the circulation path.
3. noun A pipe for leading the hot gases from the top of a blast furnace downward to the regenerators, boilers, etc.

Similar words

downcome downtake rone pipe drainpipe downpipe downwell drain pipe descent dumper drainer

Often followed by

and area is to backup seal of tubes liquid