Readily inspectable and cleanable emergency valve for storage tank

Abstract From the Canadian patent

An emergency valve assembly for a tank adapted to contain liquid such as for instance hazardous material with the valve assembly including a valve head for closing the discharge port from the tank in an operative closed position of the valve head and with a first operating unit coacting with the valve head for selectively opening the latter and a separate second operating unit coacting with the valve head for automatically closing the latter. The first operating unit has a portion adapted for accessibility from exteriorly of the tank and includes a fluid power connection to the first operating unit for select-, tively supplying pressurized fluid to such operating unit; for causing opening …