Filter regulators

Pressure regulators and filter-regulators are used in pneumatic circuits to stabilize supply pressure and condition compressed air upstream of solenoid valves, pneumatic actuators, cylinders, positioners, and control instruments. Selection should be based on inlet pressure, required outlet pressure, air flow rate, filtration grade, condensate drain type, and the installation layout of the pneumatic circuit.

This category includes Hafner Classic-line air regulators and filter-regulators, Futura-line FS filter-regulators, and two- or three-piece FRL assemblies. Classic-line filter-regulators are available with G 1/8" to G 1" ports, flow capacities from 600 to 4500 l/min, inlet pressure from 1.5 to 15 bar, adjustable outlet pressure from 0.5 to 12 bar, and 20 micron filtration, with semi-automatic or automatic condensate drain depending on model.

Futura-line FS filter-regulators cover G 1/4" to G 1" connections, flow rates up to 13000 l/min, inlet pressure up to 16 bar, and outlet pressure adjustment from 0.5 to 8 bar, with 5 micron filtration and either semi-automatic or automatic drain options. Where pressure reduction is required without integrated filtration, the Futura-line regulator ranges include KPRB, KPRG, KRBE, and KREG, with flow capacity up to 14200 l/min and outlet pressure range from 0.5 to 8 bar.

Classic-line pressure regulators also include versions with quick exhaust, versions for water service, and basic R/R-0 regulators, with flow rates from 600 to 6200 l/min and outlet pressure from 0.5 to 12 bar.

During installation, attention should be given to flow direction, drain orientation, access to the filter bowl, air quality, pressure dew point, cyclic consumption peaks, and pressure drop under load. Condensate, oil carryover, particulate contamination, or undersized components can affect valve shifting, actuator response time, and control loop stability.