A device that maintains the pressure in a fluid flow line, less than its inlet pressure within a constant band of pressures, regardless of the rate of flow in the line or the change in upstream pressure.
a device that reduces incoming water pressure for low-pressure drip systems. Typical household water pressure is 50 to 60 psi while drip systems are designed to operate at around 20 to 30 psi depending on the manufacturer.
A pressure regulator is used to reduce high water pressure to the range suitable for drip irrigation. They are available in various flow ratings and pressure settings. They need to be matched to the drip irrigation system requirements. Some have pipe threads and others have garden hose thread ends.