Pneumatic FRL Units: Filter-Regulators, Lubricators and Air Preparation Sets

Air leaving a compressor carries three things: water, oil vapour and particles. Fed into a circuit untreated, they corrode valve spools, wear cylinder seals and clog silencers. The FRL group — filter, regulator, lubricator — sits at the inlet of a pneumatic circuit and deals with all three.

The unit has three stages. The filter passes the air through a cyclone chamber, collecting water droplets and coarse particles in the bottom of the bowl; the accumulated water is drained through a manual or automatic drain. The regulator reduces the variable line pressure to the fixed value the circuit needs and holds it there; the small gauge on top shows the setting. The lubricator adds a controlled mist of oil to the air, lubricating the internal surfaces of valves and cylinders.

Not every circuit needs all three stages. The filter + regulator pair (FR) is the most common arrangement, and most modern cylinders are lubricated for life and run without a lubricator. A lubricator is added for older cylinders, high cycle rates and percussive hand tools. Once lubrication has been started it should not be stopped: the oil washes away the factory grease, and if lubrication ceases the component runs dry.

Selection turns on two values. Port size (1/4", 3/8", 1/2", 1") is set by the flow in the line; a unit sized below the line acts as a restriction, causing a pressure drop and slowing the cylinders. Body type is chosen for the environment: a plastic bowl is economical but cracks where solvent vapours are present, so metal-bodied units are used in those conditions.

Alongside complete units, this group also carries spare bowls, regulator gauges and FRL oil — including food-grade oil for food plants. For the rest of the circuit see the «Pneumatic Valves» and «Pneumatic Cylinders» pages.

Firetech products are searched for in the field by the manufacturer's part number, not by our stock code. The code follows this pattern: SERİ + VARYANT — for example ZDB6 VP1. Every code in the series below can be supplied; some are held in stock ready to ship.

These products are searched for in the field by the manufacturer's part number, not by our stock code. The code follows this pattern: TİP + HORTUM ÖLÇÜSÜ + DİŞ — for example AC901-15. Every code in the lists below can be supplied; some are held in stock ready to ship.