초록 ▼

A gas flow control valve which enables mass flow to be measured using a flow straightener in a valve entry duct, a tube for lengthening the entry duct into the valve, a valve element exit port with suitably radiused edges and a flow stabilizer in the valve exit duct. Upstream and downstream pressure

A gas flow control valve which enables mass flow to be measured using a flow straightener in a valve entry duct, a tube for lengthening the entry duct into the valve, a valve element exit port with suitably radiused edges and a flow stabilizer in the valve exit duct. Upstream and downstream pressure taps are positioned immediately upstream of the flow straightener and downstream of the flow stabilizer respectively. This enables the flow rate to be controlled not by the formulas traditionally used for valve dimensioning, but by formulas derived from more accurate formulas used for calculating mass flow with standard members of a fixed restriction type.

대표청구항 ▼

[ I claim:] [1.] A gas mass flow metering valve, comprising an entry duct, an exit duct, a valve element having an exit port, a seal ring cooperating with said valve element, said seal ring being made to rotate by operating means, and means for measuring the pressure upstream and downstream of the v

[ I claim:] [1.] A gas mass flow metering valve, comprising an entry duct, an exit duct, a valve element having an exit port, a seal ring cooperating with said valve element, said seal ring being made to rotate by operating means, and means for measuring the pressure upstream and downstream of the valve element and the valve gas temperature, characterised in that fluidly coupled to said entry duct is a flow straightener, immediately downstream of which, within the valve body, there is positioned the upstream pressure measuring means, said entry duct being prolonged by a prolongation tube into the interior of the valve element to a point proximate the convergence region in correspondence with said exit port through an aperture in the valve element opposite said exit port, said valve element exit port having an edge geometry including a converging curvature arranged to convey the gas flow in a direction substantially parallel to the axis of the exit duct, which is provided in its interior with a flow stabilizer, the downstream pressure measuring means being positioned within the valve upstream of said flow stabilizer, proximate said exit port.