Constant flow regulator
Energy Efficient Pumping Systems, a design guide (BG 12/2011), written by Chris Parsloe and published by BSRIA in 2011, defines a constant flow regulator (CFR) as: ‘…a self-acting valve that acts in response to changes in pressure at its inlet port. A piston will open or close against a spring to control differential pressure across the inlet port. The area of the inlet port can be adjusted to limit the flow to the required design flow within the differential pressure operating range of the CFR.’
Selection of Control Valves in Variable Flow Systems (BG 51/2014) written by Chris Parsloe and published by BSRIA in June 2014, defines a constant flow regulator as: ‘…a self-acting valve that (provided the valve is operating within its recommended differential pressure range) limits the flow rate to an approximately constant set value, regardless of changes in system pressures.’
--BSRIA
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