.~ Expansible chamber operated by valve actuator for draining riser
DEFINITION
Classification: 137/281
(under subclass 272) Apparatus including an expansible chamber near the bottom of the riser and operated by movement of the riser and/or valve actuator to evacuate water from the riser as the valve is closed or receive the drain or waste after the valve is closed, and to refill the riser as or before the valve is opened.
(1) Note. These are primarily anti-freeze devices for storing the water trapped in the riser at the lowest point above the valve, and returning it to the flow path at the start of the next discharge.
SEE OR SEARCH THIS CLASS, SUBCLASS:
62, for low temperature responsive drains.
301+, for other antifreeze protection of hydrants.
568, for reserve or surge receiving means for distribution systems having pumps.
596+, for distribution systems provided with stop and waste means or drains. 777+, for expansible chamber devices, per se.
SEE OR SEARCH CLASS
123, Internal-Combustion Engines,
41.14, for means for withdrawing and storing the water from the cooling system of an internal combustion engine when the engine is not operating.
138, Pipes and Tubular Conduits,
27+, for freeze protecting expansible chambers for pipes and tubular conduits.
