Abstract: A paint circulating system is suitable for providing paint to applicators in a product finishing facility. The system includes a pump for pumping paint around the system and a back-pressure regulator (BPR), which substantially eliminates pressure fluctuations of paint in the system upstream of the BPR. A controller is provided for controlling the pump and the BPR to operate in one of a flow mode, wherein a required flow rate of paint around the system is maintained, and a pressure mode, wherein a pressure of paint between the pump and the BPR is maintained. The paint circulating method includes switching operation of the pump and the BPR between the flow mode and the pressure mode.

Abstract: A paint circulating system back pressure regulator comprises a flow passage for paint, at least part of which is disposed between a fixed structure and a moveable surface which is moveable to vary the width of the flow passage so as to regulate a pressure of paint upstream of the regulator. The regulator is also provided with a chamber having an opening for communicating with a supply of a pressurised fluid for controlling operation of the regulator.