Abstract: The present invention relates to fluid delivery systems comprising valve assemblies that provide for a more stable and reliable delivery system for a fluid, for example a gaseous fluid, from a tank by utilizing vacuum to open the normally closed valves assemblies. The present invention also relates to methods of delivering a fluid from a tank, assembling and operating the valves assemblies, as well as retrofitting existing tanks with such systems.

Abstract: The present invention relates to fluid delivery systems comprising valve assemblies that provide for a more stable and reliable delivery system for a fluid, for example a gaseous fluid, from a tank by utilizing vacuum to open the normally closed valves assemblies. The present invention also relates to methods of delivering a fluid from a tank, assembling and operating the valves assemblies, as well as retrofitting existing tanks with such systems.

Abstract: Systems and methods for metering fluid flow are disclosed. A valve may generally include an orifice plate, and a disc positioned adjacent to the orifice plate. An orientation of the disc relative to the orifice plate is adjustable to regulate a fluid flow rate through the valve. An effective area of an aperture in the orifice plate may be manipulated to adjust the fluid flow rate. In some configurations, the valve may provide sonic flow control or differential pressure regulation. In some applications, a controller may adjust the orientation of the disc relative to the orifice plate to maintain a substantially constant pressure drop across the orifice plate in order to determine a fluid flow rate through the valve.