Expansion valve

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(Steam Engine) a cut-off valve, to shut off steam from the cylinder before the end of each stroke.

See also: Expansion

References in periodicals archive ?
Limited Tenders are invited for Procurement Of Thermostatic Expansion Valve
NEW YORK -- Freescale Semiconductor and Microstaq are collaborating on the development of an intelligent refrigerant superheat control system that combines Freescale's microelectromechanical systems (MEMS) pressure sensing, processing and control technology with Microstaq's revolutionary MEMS silicon expansion valve (SEV).
While the use of the electronic expansion valve allows for energy saving control strategies, the complexity of this subassembly requires a larger bill of materials and extra effort in fabrication when compared to a simple piston expansion device integrated into a check valve.
Each evaporator has a dedicated electronic controller and expansion valve and the Copeland Scroll condensing units comprise standard and electronic scroll compressors.
For the conventional design, a low temperature well below the ambient temperature is achieved through an expansion device (capillary tube, expansion valve, short tube, and the like), resulting in a surface temperature lower than the corresponding dew-point temperature.
Tenders are invited for Thermostatic Expansion Valve 7.
The unit was tested in heating mode in psychrometric chambers with two indoor units and steady state data were used to train the compressor and electronic expansion valve (EEV) model, to estimate the control algorithm of the opening of the expansion valve and to tune the refrigerant charge for the system model.
PEECTM operation provides the system with a sophisticated fan speed control which allows the unit to operate when achievable at the optimum condensing temperature in relation to its evaporating temperature without jeopardizing liquid quality to the expansion valve.
The ideal vapor compression cycle consists of four processes: (1) isentropic compression in a compressor, (2) isobaric heat rejection in a condenser, (3) isenthalpic expansion in an expansion valve, and (4) isobaric heat absorption in an evaporator.
The externally equalized thermal expansion valve also helps provide more precise control at partial and low loads.