Abstract: Fluid is transferred from a reservoir to a tank by means of a pump which pumps fluid through a conduit communicating with the tank and separably coupled to the reservoir. Operation of the pump is governed by a control mechanism that is operable to enable and disable operation of the pump. The control mechanism is connected to an energy source via adjustable switching means which in one of its positions is operable to disable operation of the pump when the level of fluid in the tank reaches a predetermined height, and in another of which it is operable to enable operation of the pump regardless of the fluid level in the tank.

Abstract: A liquid handling system for filling tanks, such as tank trucks, particularly suitable for handling volatile fluids, employing a fill conduit and an emergency shutoff valve located at the upper end of the fill conduit. The emergency valve employs an annular, normally open, valve element axially displaceable to a shutoff position upon the liquid level within the tank reaching a predetermined maximum depth. Valve element operation is regulated by a control piston subjected to subatmospheric pressures produced by liquid flow through the valve and upon the liquid level reaching a predetermined depth the control piston is actuated to cause the valve element to terminate fluid flow. The emergency shutoff valve may be employed in conjunction with a variable rate flow valve connected in series therewith to produce a versatile tank filling system.