Abstract: A guided-float accumulator suitable for use with a hydraulic system for an oil well blowout preventer is provided with a wing shut-off valve. Radially inwardly directed outlet parts are aimed at the bottom of the valve wing to generate unbalanced reaction forces which oppose the bernoulli effect forces caused by rapid movement of fluid through the chamber of the shut-off valve, thus preventing premature closing of the valve.

Abstract: A guided-float accumulator suitable for use with a hydraulic system for an oil well blowout preventer is provided with a vented float movable along a transversely centered, normally vertical guide rod according to the level of the liquid fill within the vessel. The vent outlet for the float and a ballast weight for the float are positioned on opposite sides of the guide rod and the float is mounted for free turning around the guide rod. Whatever the degree of liquid fill of the vessel, sidewise tilting of the vessel will be accompained by rotation of the vent outlet to the then-high side of the guide rod to maintain the float directly vented to the ullage space of the vessel.