WHAT ARE F.R.L.’s?HOW THEY WORK

WHERE TO USE THEM

THE QUALITY NAME

FORM NO. 9X018 MINI FILTER - REGULATOR - LUBRICATOR 03-2008 Page 1

INSTRUCTION SHEETMINIATURE AIR LINE FILTERS, REGULATORS AND LUBRICATORS

Product Bowl Max. Inlet Pressure Temperature RangeFilter Polycarbonate 150 PSI 40° F to 125° FFilter Metal 250 PSI 40° F to 160° FRegulator 250 PSI 40° F to 120° FLubricator Polycarbonate 150 PSI 40° F to 125° FLubricator Metal 200 PSI 40° F to 160° F

3-60 PSI

Although you may think a big filter is moreeffective, the reverse may actually be true iftoo little air passes through. Always selectfilter size based on your air flow or SCFMrequirements.

How small is too small - As long as thepressure difference between the inlet andthe outlet of the filter does not exceed 3 PSIat the required air flow (SCFM), the filter isnot too small. For more information, pleaserefer to the FRL sizing chart in the MiltonCatalog, page 60.

What a filter does and doesn’t do - Aproperly selected andinstalled filter removesparticulate matter andwater condensate.However, it does not andcannot remove water

vapor from the air. Water vapor must beconverted to water condensate before thistype of filter can remove it (See the OTHERFILTERS section).

Water vapor and water condensate -Water vapor is an invisible gas; watercondensate is a liquid, even if it is in mist ordroplet form. To convert water vapor to acondensate, the air must be cooled down -actually, down to or below the "dew point."

The dew point is the temperature at whichdew or water condensate forms. It varieswith the RH (Relative Humidity). It’s low withlow RH and approaches ambienttemperature with high RH.

This explains why you sometimes see waterdroplets or mist coming from a blow gun orpaint sprayer when there is no "apparent"water in the air lines. The rapid expansion ofthe air as it leaves the blow gun or sprayercauses the air’s temperature to drop (sameprinciple as an air conditioning system). Ifthis temperature falls below the dew point,the water vapor in the air line converts instantlyto water condensate.

MICRO-FILTERSAlthough the Micro-Filter is the simplest ofthe three basic air control devices, it is alsothe least understood and the one mostfrequently installed improperly. Read on.

How they work -These filters remove twokinds of contaminants: (1) solid, particulatematter such as rust and pipe scale and (2)water condensate. The first is removed by anominally rated 40 micron porous sinteredmetal element. However, because of it’sunique "tortuous path" design, it will actuallytrap particles down to 10microns in size (about0.0004 inches)

The water is removedthrough a violent swirlingaction imparted to the air by a set of fixedvanes at the top of the filter. The process isexactly like that of the spin-dry cycle in awashing machine. Centrifugal force throwsthe water droplets against the side of thebowl where they roll down and collect at thebottom.

Small is better -The more rapidly the air isswirled, the more effectively the watercondensate is thrown out against the filterwall. If you pass the same volume of air(SCFM) through a small filter and a largefilter, it will swirl more rapidly in the small one.

Condensate removal in a Micro-Filter.

" The filter ... is the one leastunderstood and the one mostfrequently installed improperly "

If you sometimes experience a problem likethis, you will require, in addition to the Micro-Filter, a desiccant dryer filter (see OTHERFILTERS section).

Choosing a different drain system -All filters (except the Mini) come with anOvernight Drain that opens when linepressure falls, after turning off thecompressor, to 5 PSI. These drains can alsobe opened manually by pushing themsideways (poly bowls) or twisting them in thedirection of the arrow (metal bowls).

You can also install an Automatic DrainValve (Model 1168) in place of the suppliedOvernight Drain Valve. These valves openautomatically whenever the water level inthe bowl reaches a certain point, whetherthe system is under pressure or not. Theseare good for high humidity conditions oraround-the-clock systems.

Metal bowl vs. polycarbonate bowl -The advantage of the poly bowl is in quickand easy water level checking. If you have asituation where water may fill the bowlbefore the overnight drain can function (e.g.,high humidity), it is helpful to be able tovisually check water level.

Other than this, the advantage is with the metalbowl. This is especially true if you are usingsynthetic oils in your compressor or havevolatile solvents in the area. (See list ofchemicals that are not compatible with polybowls.)

One filter is never enough - A well -designed system requires a minimum of twofilters: (1) a master filter near thecompressor and (2) a smaller filter at each

work station or air operated device. The masterfilter is usually a 1/2" NPT or larger unit.

This filter should never be installed at the outputof the compressor, but rather at the output ofthe after-cooler or the receiving tank. Theseunits allow the hot, high pressure air from thecompressor to cool down enough to condenseout much of the water vapor. The main line filterand regulator should be placed at least 20 Feetfrom the compressor.

The additional filter at each station, besidesremoving still more condensate, also traps anydebris (rust and pipe scale) that may make itsway down the distribution pipe. Try to locate thisfilter as close to the device as possible.

Installation tips - Align the filter vertically, withthe drain at the bottom. Note that the air fromthe compressor enters the "IN" port and exitsthe "OUT" port. If connected backwards, thefilter will still pass air but will not extract thewater condensate.

Easy maintenance - Since there are nomoving parts to wear out, there is little to gowrong. Periodically wash the sintered filterelement in a detergent solution and blow it out;if too clogged to be washed, replace it.

Sometimes a Micro-Filter alone is not theanswer. Although they remove much of thewater, in some applications, such as spraypainting, it’s not enough.

When you need exceptionally dry air oressentially oil-free air, you can choose from twoother filter types: (1) the desiccant dryer and (2)the oil removing filter.

The desiccant dryer filter - This is the ultimatefilter for dry air; it takes over where the Micro-Filter leaves off. This filter absorbs directly,through a chemical process, the water vapor inthe air.

So effectively does it remove water, that the airfrequently has a dew point of 0°F or lower.

OTHER FILTERSAIR IN AIR OUT

FIXED VANES

WATER DROPLETS

WATERCONDENSATE

DRAIN

SINTERED FILTER

BAFFLE

When you need a desiccant dryer

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Normally, you will neither feel nor hear anyair coming from this hole. If you do, it meanseither: (1) the regulator diaphragm has aleak, (2) the little valve under the knurledcap is dirty or (3) the regulator has beeninstalled backwards. If, on a new installation,the regulator does not respond properly oryou hear air escaping, make sure you havenot reversed the IN and OUT ports - ithappens.

Pressure ranges - Regulators come in twostandard ranges: (1) 2 to 125 PSI and (2) 10to 250 PSI. The maximum inlet pressure ineither case is 250 PSI. A special lowpressure mini-regulator is also available thatcovers 3 to 60 PSI. This is the sameregulator that is used on the Model 1174Desiccant Dryer system.

These devices play a vital role in many airdelivery systems. Be sure you select thetype best suited to your applications.

Two types available - Lubricators come intwo basic styles: (1) the drip type and (2) thewick type. The drip type is the most popularand the one best suited to the averagerepair shop application. The wick type isnormally used for industrial applications.

The drip type - This style injects lubricationinto the system by allowing oil dropsperiodically to drop into the air stream. Therate at which the drops enter the stream isfully adjustable. And once adjusted, theadjusting knob can be removed to preventtampering.

The question is: How much oil to inject andhow is this accomplished? For the averagerepair shop, 3 to 4 drops per minute is agood starting point; you can raise or lower itas you see fit. Since the lubricator deliversoil only when air is flowing, here is onemethod for setting the drip rate: Connect atubeless tire valve to the system (via a tirechuck) and let the air pass through freely.This is about the same volume of airconsumed by an impact wrench. Adjust thedrip rate to produce 3 to 4 drops per minute.

WARNING! - ALL FRL’s

FOR COMPRESSED AIRSERVICE ONLY.

NOT TO BE USED ONLIFE SUPPORT OR

BREATHING AIRSYSTEMS.

This is sufficiently dry for practically anypurpose, including spray painting.

However, this drying efficiency comes with aprice. The desiccant that absorbs the watervapor eventually becomes saturated withwater and can no longer absorb anymore.Fortunately, you are alerted to this by achange in desiccant color - from bluish-whiteto pink.

When this happens, you have two choices,depending on which desiccant system youare using. If it is the rechargeable type,simply remove the desiccant, dry it in avented oven at 275°F for two or three hours,then put it back in the filter.

If it is the disposable type, such as the MiniIn-line Desiccant Dryer (Models 1173/1174),it’s even easier - just throw it away.

The Mini In-line Dryer is designed for thoseusers who do not need full-time dry air andwho wish to avoid the cost of installing arechargeable desiccant system. One MiniDryer will supply enough bone-dry air,depending on humidity, to spray paintseveral cars.

Remember though, all desiccant dryersmust be preceded by a Micro-Filter toremove the water condensate. In addition,they should also be preceded by an oil-removing filter (described below). Failure todo this will result in short desiccant life.

Oil-removing & Coalescing filters -In addition to water and particulate matter,oil can also be a contaminant in an airsystem. This is especially true in paintspraying.

A special series of Sub-Micron Oil RemovingFilters is available for this purpose. It willremove particles down to 0.9 microns (0.03microns for coalescing filters), over forty toone hundred times as small as thoseextracted by the standard Micro-Filter. Thisis small enough to capture oil vapors (e.g.,compressor blow-by) as well as water misttoo fine to be removed by a standard filter.

REGULATORS

Proper sequence of F-R-L components.

LUBRICATORS

The wick type - In this system, oil istransferred to the air stream by having theair pass over a wick saturated in oil. Theamount of oil injected this way is determinedby how much of the wick is exposed to theair. The normal factory setting is for 50%wick exposure. Raise or lower the wick, byopening the lubricator, for more or less oil.

The wick type lubricator requires a fairly highvolume of air to function - a minimum of 30SCFM. This is roughly equivalent to seven,1/2-inch impact wrenches operatingsimultaneously. Generally speaking,compressors of 10 horsepower or less donot have the capacity to handle a wick typelubricator.

Poly bowl vs. Metal bowl - If you are usinga standard lubricant, such as 10 weightnon-detergent motor oil, either bowl issatisfactory. If you are using a proprietary airtool oil or a specialty lubricant, opt for themetal bowl. Some of these special lubricantsmay damage poly bowls. For rotary screwcompressor applications use a metal bowl.Poly bowls damaged by chemicals are notcovered by warranty. Always install alubricator after a filter or regulator, neverbefore.

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It achieves this exceptional filtration througha white borosilicate element that can bereplaced when necessary. Similar to thestandard filter, these units also have anover-night drain. Since they are not intendedto remove large quantities of water, theyshould always be preceded by a Micro-Filter.

Regulators, despite their precision valvingsystem, can be very long-lived devices. Tento twenty years is not unusual.

Keep it clean - The secret to this longevityis clean air. Always, without exception,precede your regulator with a Micro-Filterand install it as close as you can get it. Thisis why the Piggyback Filter-Regulator orFRL Trio is such a good choice - they alwayscome with a filter. And never precede aregulator with a desiccant dryer filter or alubricator nor use Teflon tape on the "IN"port (use standard pipe dope).

That little hole in theside - This is a relievingport that allows theregulator to be used ond e a d - e n d e dapplications. Thismeans that you canraise or lower thedesired pressurewithout any air flow.

VENTHOLE

FILTERSThe basic air control devicefor all systems. Removessolid particulate matter andwater condensate. Availablein a wide variety of sizes.

REGULATORSA full line of regulators inboth standard pressure (2-125 psi) and high pressure(10-250 psi). All metalconstruction.

LUBRICATORSPrecision lubricators to auto-matically provide essentialoil to all your pneumatictools. Can be adjusted todeliver the correct amount.

PIGGYBACK REGULATOR The ideal package for a basicair control system. Samefeatures as our standardregulator and standard Micro-Filter. Easy installation.

OIL REMOVING FILTERRemoves oil and oil vaporsfrom the air line. Preventsoil pull-over from enteringyour paint spray gun andmarring the paint job.

F-R-L TRIOA complete system for standardshop applications. Includes astandard Micro-Filter, regulatorand lubricator in one easy-to-install package.

MINI F-R-L TRIOIdeal for low air volumeapplications such as art studios,model shops and laboratories.Regulator, filter and lubricatoralso available separately.

MINI AIR STATIONA self-contained desiccant filterfor spray painting. Completewith desiccant and lowpressure regulator. Clips toyour belt.

DESICCANT DRYER SYSTEMFor the ultimate in water-free and oil-free air youcan’t beat the Deluxe Desiccant Dryer System.Complete with Micro-filter, oil removing filter,pressure regulator and desiccant dryer. Ready togo with nothing else to buy.

A COMPLETE LINE OF COUPLERS, PLUGS, CHECK VALVES, SAFETY VALVES ...

CHEMICALSNOT TO BE USED

WITH POLY BOWLSDo not use synthetic oils

or oils containingphosphate esters or

chlorinated hydrocarbons.They can carry over fromthe compressor into theair lines and attack or

crack poly bowls. Do notexpose these bowls, even

from external sources, to: alcohol,

carbon tetrachloride,trichlorethylene, acetone,

paint thinner, cleaningfluids and similarmaterials. These

chemicals and othersimilar chemicals cancraze or crack a poly

bowl. If in doubt, use ametal bowl, especially

since poly bowlsdamaged by chemicals

are not covered bywarranty.

ROTARY SCREWCOMPRESSORSFor these applications

use a metal bowl.

METAL BOWLLUBRICATORS

The sight glass inthese units will crackif exposed to alcohol

or alcohol based fluids.

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The air management peopleSee your jobber for the full product line

4500 W. Cortland Street, Chicago, Illinois 60639Phone: (773) 235-9400 FAX: (773) 235-3221Web Site: www.miltonindustries.com