pneumatic reference data · perfect gas laws. the relationships between pressure, volume, and...

Bulletin 371C

ROSS CONTROLS®

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PNEUMATIC PRINCIPLES ....................................2–4

GLOSSARY OF USEFUL TERMS .............................5

VALVE RESPONSE TIME ..........................................6

FLOW COEFFICIENTS ..............................................7

STANDARDIZED TESTING .......................................8

FLOW CHART FOR Cv = 1 ........................................9

CYLINDER VOLUME ...............................................10

VALVE SIZING .........................................................11

PNEUMATIC SYMBOLS ....................................12–14

PORT IDENTIFICATION ....................................14–15

CONVERSION FACTORS ........................................15

WARRANTY..............................................................16

TABLE OF CONTENTS

PNEUMATIC REFERENCE DATA

� ROSS CONTROLS®

PNEUMATIC PRINCIPLES

Pneumaticsisthestudyofthemechanicalpropertiesofgases.Inindustrialapplicationsthegasinvolvedismostcommonlycompressedair.Themechanicalpropertieswithwhichwearemostconcernedarepressure, volume andtemperature. Therelationshipsbetweentheseproperties,andthemeaningsofsomebasicpneumaticterminologyarediscussedbelow.

Force and Pressure. Consider the diagram of thecylindersbelow.

Figure 1

When the force of 60 pounds is applied to the piston,theairinthecylinderiscompressed.Thiscompressioncontinues until the upward force on the piston is thesameasthedownwardforce,thatis,untiltheforcesareinequilibrium.

Theforceoneachsquareinchofthepistonis:

forceonpiston=60lb=15lbperin�(psi)

areaofpiston4in�

Thisforce per unit area iscalledpressure. Thetermsforce andpressure mustnotbeconfused.Forceisexpressedinunitssuchaspounds, tons, kilograms, etc., whilepressureisexpressedaspounds per square inch, tons per square mile, kilograms per square meter, etc.

Ingeneralterms,then:

pressure =force area

Conversely,theforceexertedonorbyanareais:

force = pressurexarea

Pascal’s Law. Pressure applied to a confined fluid istransmittedundiminishedinalldirections.InthediscussionofFigure1welearnedthattheforceappliedtothepistonproducesapressureof15psi(poundspersquareinch).Pascal’sLawsimplysaysthatapressureof15psiisappliedtoallsurfacescontainingtheair,i.e.,thewallsandbottomofthecylinderaswellasthepistonsurfaceitself.

60 lb

Piston area4 sq in

60-lb upward forceresulting fromcompression

Atmospheric Pressure. Thepressureproducedontheearth'ssurfacebytheweightoftheairsurroundingtheearthwasmeasuredbythe17th-centuryscientist,EvangelistaTorricelli. He filled a 36-inch glass tube(sealedatoneend)withmercury,andplacedhisfingerovertheopenendofthetube.He then stood the tube onendinadishofmercuryandremoved his finger. Somemercuryflowedfromthetubeinto the dish, but a columnof mercury 30 inches tallremained in the tube. Thepressure of the atmosphere,he reasoned, is sufficient tosupportacolumnofmercury30incheshigh.Morerefinedtestshaveshownthisatmospheric pressure tobeequalto14.69poundspersquareinch.

30"Hg

Vacuum

Figure 2

Gauge Pressure. Atmosphericpressureisapartofoureverydayenvironment.Wedon’tnoticethepressureonus,anditisconvenienttothinkofatmosphericpressureas“zero”pressure.Sowemeasurepressurestartingatthiszeropoint,andapressuresomeasurediscalledgauge pressure. A common abbreviation for gauge pressuremeasurementsispsig (poundspersquareinchgauge).

Absolute Pressure. When dealing with the effects ofpressureongases it isnecessary toconsider the totalpressureonthegas.Wecannolongerignoretheeffectof atmospheric pressure as we do when we measuregaugepressure.Thistotalpressureactingonagasiscalledabsolute pressure.

absolute pressure =gaugepressure+14.69

Youwillrecognize14.69asthepounds-per-square-inchmeasureofatmosphericpressure.

To distinguish absolute pressure from gauge pressuremeasurements,weuseunitssuchaspsia (poundspersquareinchabsolute).

Absolute Temperature. Absolutetemperatureisbasedonatheoretical“lowest”temperature.Thislowesttemperatureisthezeropointforthetwoabsolutetemperaturescalesincommonuse,theRankinescaleandtheKelvinscale.

TheRankinescaleisbasedontheFahrenheitdegree.

Rankine temperature =Fahrenheittemperature+459.67

Thus, 0°F = 459.67°R, although for most practicalapplicationsitistakenas460°R.

www.rosscontrols.com 3


TheKelvinscaleofabsolutetemperatureisbasedontheCelsiusdegree.

Kelvin temperature = Celsiustemperature+�73.16

Thus,0°C=�73.16°K.Again,formostpracticalpurposesitistakenas�73°K.

Perfect Gas Laws. Therelationshipsbetweenpressure,volume, and temperatureareexpressed in threebasic“laws” which we will discuss below. These laws applytoanidealgas,butarealsoremarkablyaccurateforthemixtureofgasesmakingupourair.

Inapplyingthese laws it is important torememberthatonlyabsolutevaluesofpressureand temperaturemaybeused.

Boyle's Law. Thislawexpressestherelationshipbetweenpressureandvolumewhentemperature is held constant. Accordingtothislaw,thevolumeofthegasinacontainerisinverselyproportionaltotheabsolute pressure onthegas,i.e., P1V1=P�V�

Letusapplythislawtofindthevolumeofthegasinthecylinderbelowaftercompression.

Figure 3

Thepressureactingonthecylinderattheleftissimplyatmospheric pressure. The absolute pressure on thecylinderafteritiscompressedis:

P�=(60÷4)+14.7=�9.7psia

WiththisinformationwecanuseBoyle'sLawtofindthecompressedvolume.

14.7x1�0=�9.7xV�

V�=14.7x1�0÷�9.7

=59.4cubicinches

Whenagasiscompresseditgetswarmer,sotheabovecalculationwouldbecorrectonlyafter thecompressed

60 lbPiston area

4 sq in

V1

120 cu in V2

P1 = 14.7 psia

P2

gashasbeenallowedtocooltothetemperatureithadbeforecompression.

Charles’ Law. This law expresses the relationshipbetweenvolumeandtemperaturewhenpressure is held constant.Accordingtothislaw,thevolumeofthegasinan expandable container is directly proportional to theabsolutetemperatureofthegas,i.e.,

V1T�=V�T1

LetustakethecylinderinFigure3andspecifythatthetemperatureofthegasis60°F.Ifweapplyheattothecontainer, as depicted in Figure 4 below, so that thetemperatureofthegasisraisedto100°F,whatwillbethenewvolumeofthegas.Notethattheloadonthepistondoesnotchange,andthereforethepressureonthegasisconstantasrequiredbyCharles’Law.

Figure 4

Theabsolutetemperaturesare:

T1=60°F+460F°=5�0°R

T�=100°F+460F°=560°R

ThevolumeofthecompressedgasaswedetermineditfromFigure3isV1=59.4cubicinches.WhenweapplyCharles’Lawtothisinformationwehave:

59.4x560=V�x5�0

V�=59.4x560÷5�0

=64.0cubicinches

Gay-Lussac’s Law. Thethirdgaslawstatesthatifthevolumeofagasisheldconstant(i.e.,confinedinarigidcontainer) the absolute pressure of the gas is directlyproportionaltoitsabsolutetemperature.Thus,

P1T�=P�T1

Aclosedcontainerwhenheatedbuildsupconsiderableinternal pressure, and can lead to an explosion of thecontainer.ThisisGay-Lussac’sLawatwork!

60 lb

V1 T1

60 lb

V2 T2

4 ROSS CONTROLS®


General Gas Law. Inpracticalapplicationsallthreeofthevariables—pressure,volume,temperature—maychange.Thethreegaslawswehavediscussedcanbeconsolidatedintoasinglegenerallawwhichprovidesforchangesinallthreevariables.Thisgenerallawissimply:

P1V1T�=P�V�T1

Letusapplythisgenerallawtothefollowingproblem.

Figure 5

Initially,theforceonthecylinder’spistonis400lb.Thiscompressesthegas in thecylinder toavolumeof1�0cubicinchesatatemperatureof60°F.Ifthegasinthecylinder isheated to�00°F,what forcemustbeon thepiston tocompress thegas further toavolumeof100cubicinches?

Becausethepistonhasanareaof4squareinches,theabsolute pressureonthegasinitiallyis:

P1=(400÷4)+14.7=114.7psia,

andtheabsolute temperaturesare:

T1=60+460=5�0°R

T�=�00+460=660°R.

Inordertodeterminetheforcethatmustbeonthepistoninordertocompresstheheatedgasto100cubicinches,wemustfirstfindthevalueofP�.Todothisweapplythegeneralgaslaw,P1V1T�=P�V�T1.

114.7x1�0x660=P�x100x5�0

P� =(114.7x1�0x660)÷(100x5�0)

=174.7psia

P�intermsoftheforceFactingonthepistonis:

P� =(F÷4)+14.7

Thenwehave,

174.7=(F÷4)+14.7

F÷4=174.7-14.7=160psig

F=160x4=640lb.

Standard Air and Free Air. In the United States thevolumeofairismostcommonlymeasuredbythecubicfoot.Ofcoursetheactualamountofairinacubicfootdependsonfactorssuchaspressureandtemperature,soithasbecomenecessarytodefineastandard cubic foot (scf) ofair.Formostindustrialapplicationsthisisacubicfootofairatapressureofoneatmosphere(14.69psia),atemperatureof68°F,andarelativehumidityof36percent.Theweightofastandardcubicfootofairis0.076�lb;1lbofstandardairoccupies13.1cubicfeet.

Inactualpracticeoneseldomencountersstandardair,butisdealingwith“free”air,thatis,theairthatweencounterineverydayexperience.Fortunately,unlessweareonamountaintoporworkingnearablastfurnace,freeairiscloseenoughtostandardairsothatwedonothavetomakecorrectionsforthesmalldifferences.

Compressed Air. Theflowofair throughavalveoranypartofapneumaticsystem isusuallymeasuredin standard cubic feet per minute (scfm). Often it isnecessary to know what this volume of air is whencompressed.Boyle’slawsolvestheproblemeasily.

Forexample,iftheairflowthroughavalveis50scfm,whatistheactualvolumeoftheairifthepressureis100psig?RememberingthatBoyle’slawrequiresthatweuseabsolutepressures,wehave:

14.7x50=(100+14.7)xV

whereVisthevolumeofthecompressedair,weobtain:

V=(14.7x50)÷(100+14.7)

V=6.4cubicfeetperminute.

Conversely,wecouldaskforthepressurerequiredtofillanautomobiletirewith�cubicfeetoffreeairifthetirehasavolumeof0.5cubicfoot.Again,fromBoyle’slawweobtain:

14.7x�=(P+14.7)x0.5

wherePisthegauge pressurerequiredtofillthetire.

P+14.7=(14.7x�)÷0.5

P+14.7=58.8

P=44.1psig.

400 lb

? lbPiston area4 sq in

120 cu in

60 F100 cu in

200 F


Absolute Pressure: Thesumofatmosphericpressureandgaugepressure. Designatedaspsia (poundspersquareinchabsolute).

Air Receiver: Acontainer inwhichair isstoredunderpressureasasourceofpneumaticpower.

Ambient Temperature: The temperature of theimmediateenvironment.

Atmospheric Pressure: Thepressureexertedby theatmosphere.Atsealevelthispressureis14.69poundspersquareinchabsolute.

Bar: Aunitofpressuremeasurementequalto105newtonspersquaremeteror14.50poundspersquareinch.

Celsius, Degree: Aunitoftemperaturemeasurementabbreviated °C. Celsius temperatures are calculatedfromFahrenheittemperaturesbythefollowingformula:

C=5(F-3�)

9

Closed Center: Pertainstothree-positionvalves;allportsareclosedwhenthevalveisinthecenterposition.

Detent: Adeviceforretainingmovablepartsinoneormore fixed positions; usually a spring-loaded devicefittingintoadepression.Positionsofpartsarechangedbyexertingsufficientforcetoovercomethedetentspring,orbyreleasingthedetent.

Directional Control Valve: Avalvewhosefunctionistodirectorpreventflowthroughselectedpassages.

Flow Rate: The volume or weight of a fluid passingthrough a conductor per unit of time. For pneumaticsystems,flowrateismostoftenexpressedasstandardcubicfeetperminute(scfm).

Fluid: Aliquidoragas.

Fahrenheit, Degree: Aunitoftemperaturemeasurementabbreviated°F.FahrenheittemperaturesarecalculatedfromCelsiustemperaturesbythefollowingformula:

F=1.8C+3�

Four-Way Valve: Now designated as a 4/� valve; afour-port,twopositionvalve.

Free Air: Airatatmosphericpressure.

Gauge Pressure: Pressureaboveorbelowatmosphericpressure. Designated as psig (pounds per squareinchgauge).

Holding Power: Amountofelectricpower required tomaintainsolenoidinitsactuatedposition.

Impulse Signal: Abrieflyappliedpneumaticorelectricsignal;amomentarysignal.

Inrush Power: Amountofelectricpowerrequiredduringtimesolenoidplungerismoving.

Media: Thefluidsused inafluidpowersystem. Inapneumaticsystemtheyaregasessuchasair,nitrogen,orvariousinertgases.

Media Temperature: Thetemperatureofthefluidwithinavalveorotherdevice.

Micron: A measurement equal to one-millionth of ameterorabout0.00004inch.

Momentary Signal: A briefly applied pneumatic orelectricsignal;animpulsesignal.

Normally Closed: A term used to describe a valvewhichblockstheflowofsupplyairwhenthevalveisnotactuated.

Normally Open: Atermusedtodescribeavalvewhichallows supply air to flow only when the valve is notactuated.

Open Center: Pertainstothree-positionvalves;outletports are connected to exhaust when valve is in thecenterposition.

Pressure: A measure of force per unit area; oftenexpressedaspoundspersquareinch(psi)orbar.

Pressure Range: The range of inlet pressures withwhichadevicecanoperatesatisfactorily.

Signal: Afluidorelectriccommandtothevalveactuatorcausingthevalvetochangeposition.

Silencer: A device used to reduce the sound levelproducedbyanexhaustinggas.

Standard Air: Airatatemperatureof68°F,apressureof14.69poundspersquareinchabsolute(psia),andarelativehumidityof36percent(0.0750poundspercubicfoot).Ingasindustriesthetemperatureofstandardairisusuallyspecifiedas60°F.

Three-Way Valve: Nowdesignatedasa3/�valve;athree-port,two-positionvalve.

Two-Way Valve: Nowdesignatedasa�/�valve;atwo-port,two-positionvalve.Alsoknowasastraightwayvalve.

Vacuum: Pressurelessthanatmosphericpressure.

GLOSSARY OF USEFUL TERMS

6 ROSS CONTROLS®

VALVE RESPONSE TIME

Mostpneumaticapplicationscallforavalvetobeusedtocontroltherepeatedfillingandexhaustingofadevice(cylinder, clutch, etc.) having a certain volume. Thetimerequiredtofillorexhaustthisvolumeiscalledthevalve response time. Thetimetofillavolumeisusuallydifferentfromthetimetoexhaustthevolume.Bothtimescanbefoundbyusingthefollowingformula:

Valve Response Time = M + (F • V)

This formula gives the time in milliseconds (msec =0.001sec)requiredtofillthevolumeVto90%ofsupplypressureor toexhaustthevolumeVto10%ofsupplypressure. MandFareaverage response constants, andtheirvaluesforeachvalvearefoundintheROSSmastercatalog.Visthenumberofcubicinchesinthevolumetobefilledorexhausted.

What is the constant M? Whenavalveisenergizedittakesanumberofmillisecondsforthevalvetoshiftandallowasteadyflowofairtobeestablishedattheoutletport.Inlikemanner,whenthevalveisde-energizedittakesanumberofmillisecondsforthevalvetoshiftandcutofftheflowofoutletairandestablishtheflowofexhaustair.Thesevalve“movement”timesaredesignatedbyMintheaboveformula.

What is the constant F? AfterthevalvehasshiftedandairflowtofillthevolumeV is established, the air flows rapidly at first, thenflowsatareducingrateaspressurebuildsupinthevolumeV.InexhaustingthevolumeV,airflowsrapidlyatfirst,thenatareducingrateasthepressurefallsinthevolumeV.Ineithercasetheaverage flow rate isrepresentedintheaboveformulabyF.ItistheaveragenumberofmillisecondsrequiredtofillorexhaustonecubicinchofthevolumeV.TheproductF•V,then,isthenumberofmillisecondsrequiredtofillorexhausttheentirevolumeVafterthevalvehasshifted.

The F values for each valve are found in the ROSSmastercatalog,andtheyaregenerallydifferentforthefilling and exhausting functions. The response timetableslisttheFvaluesundertheheadings“In-Out”and“Out-Exh.”ClearlythevaluesundertheIn-Outheadingaretobeusedwhenavolumeisbeingfilled,andthevalues under the Out-Exh heading are used when avolumeisbeingexhausted.

Useofthevalveresponsetimeformulaisillustratedbythefollowingproblems.

Problem A: Howlongwillittaketofilla100-cubic-inchchamberto90%ofsupplypressureusinganISOsize�metalspoolvalvewithsinglesolenoidcontrol?

Solution A: AverageresponseconstantsforthisvalvearefoundintheROSSmastercatalog.Forthesize�seriesW60(metalspool)valvethevaluesareM=41andF=1.5. TheFvalueof�.4 isfortheexhaustpathsandsoisnotneededforthisproblem.

Putting these M and F values into the valve responsetimeformulawehave:

AverageResponseTime =41+(1.5)(100)

=41+150

=191msec

Thevolumeof100cubicincheswouldbefilledto90%ofsupplypressurein191milliseconds,orlessthan�/10ofasecond.

Problem B: WhatSeries�7,normallyclosed,3/�valveisneededtofilla1000-cubic-inchvolumeto90%ofsupplypressureinlessthan1/�second(500msec)?

Solution B: Putthegivendataintothebasicformula:

500=M+(F•1000)

NowwemustfindthevaluesofMandFthatmaketheright-hand side of the equation less than 500 msec.WecanshortenourworkbynotingthatthedominantquantityintheformulaisF•1000.ThereforewemustfindavalueofFthatwillmakeF•1000lessthan500,i.e.,Fmustbelessthan0.5.

IntheROSSmastercatalogwefindtheresponsetimeconstants for Series �7, 3/�, normally closed valves.ThefirstFvalue that is lessthan0.5 is0.43. TheMvalueis11.

Puttingthesevaluesintothebasicformulaweobtain:

AverageResponseTime =11+(0.43)(1000)

=11+430

=441msec

Weseethatthevalvetobeselectedisthelargerofthetwo1/�-inch valves. In theROSSmaster catalogweidentifythisvalveasmodelnumber�773B4001.


Theflowcoefficient(Cv)ofapneumaticdeviceisameasureofthedevice'sabilitytopassair.Theamountofairthatcanflowthroughvariousvalves,forexample,isindirectproportiontothesizesoftheirflowcoefficients,forgiveninletandoutletpressures.

Airflowthroughavalve(orotherdevice) ismeasuredin the laboratoryundercarefullycontrolledconditions.From this measurement plus measurements of theinlet and outlet pressures, the flow coefficient can bedetermined.Therelationshipbetweenthesefactorsatatemperatureof68°F(�0°C)isexpressedinthefollowingformula:

Q = 0.98 Cv P(P2 + 14.7)

where Q = air flow in standard cubic feet per minute(scfm)

Cv =flowcoefficient

P1 =inletpressure(psig)

P� =outletpressure(psig)

P = pressure drop across valve (psi) =P1–P�

Knowing the flow coefficient and the inlet and outletpressures, theflowthroughavalvecanbedeterminedusingthisformula.

Asimplerway,however,todetermineairflowistousethegraphonthepage9.ThisgraphisbasedontheaboveformulawhenCv=1.SinceairflowisproportionaltoCv,thisgraphcanbeusedforanyCvvalue;simplymultiplytheairflowrategivenonthegraphbythenewCvvalue.

Example: Givenasupplypressureof1�5psig,apressuredropof7psi,andavalvewithaCvof4.�,findtherateofairflowthroughthevalve.

Fromthe7psipressuredropvalueatthebottomofthegraph,moveupwardtothesupplypressurelinefor1�5psig.Fromthispointmovetotheleftandreadtheairflowrate:30scfm.SincethisistheairflowrateforCv=1,multiplyby4.�toobtaintheairflowrateforthevalveinthisexample.30x4.�=126 scfm.

Determining the Cv Required of a Valve Operating a Cylinder: Thechartsonpages10and11canbeusedtodeterminethevalveCvrequiredtooperatecylindersofvarioussizes.Thechartonpage10showsthedisplacedvolumeofcylinderswithvariousstrokesanddiameters.Knowing thevolumeof thecylinderand thenumberofstrokesperminutethecylindermustmake,thechartonpage11canbeusedtodeterminetheminimumCvthattheoperatingvalvemusthave.

Parallel Connection of Pneumatic Components: Ifseveralpneumaticcomponentsareconnectedinparallel,theflowcoefficientofthecombinationissimplythesumoftheflowcoefficientsoftheseveralunits.Forexample:

Cv1

Cv�

Cv3

CombinedCv=Cv1+Cv�+Cv3

Series Connection of Pneumatic Components: Ifseveralpneumaticcomponentsareconnectedinseries,the flow coefficient of the combination is a little morecomplicated.Forexample:

Cv1 Cv� Cv3

1 111 (Cv)� (Cv1)�(Cv�)�(Cv3)�

UsingCvvaluesmustalwaysbetemperedwithgoodjudgement. Flow coefficients are determined in thelaboratoryundersteadyflowconditions,astatethatexistsonlypartofthetimeinanindustrialpneumaticsystem.Someallowancemustbemadeforthevalveresponse time required to establish steady flowconditions.(SeediscussionofValveResponseTimeonpage�.)TheuseofCvvaluesisjustoneareainwhichtheexperienceandjudgementofthepneumaticdesignerbecomeimportant.

CombinedCv:

FLOW COEFFICIENTS

=++

Δ

Δ

8 ROSS CONTROLS®

STANDARDIZED TESTING

Theillustrationbelowshowsastandardizedtestset-upestablishedbytheAmericanNationalStandardsInstitute.ROSSengineeringpracticecallsforstrictadherencetothenewtestingstandardsestablishedbyANSI.

TheadoptionofthenewANSItestingstandardsbythepneumaticsindustrywillbeamajorstepforwardineliminatingtheconfusionaboutCvratingswhichhassometimesexisted. Acceptablevariations in instrumentationand testhookupcanstillyieldvariationsup to15percent inCvvalues.However, thiswill still representamajor improvementover theextremevariationswhichhavesometimesexistedinthepast.

0=upstreamtemperature

P1=pressureatupstreamtap

ΔP=pressuredrop

D=insidediameterofconductor


FLOW CHART FOR Cv = 1

10 ROSS CONTROLS®

CILYNDER VOLUME

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VALVE SIZING

1� ROSS CONTROLS®

FLUID CONDUCTORS Working Line

Exhaust Line or Control Line

Lines Crossing

Lines Connected

Mechanical Connection (Shaft,Rod,etc.)

Fixed Restriction

Variable Restriction

Flexible Line

Plugged Port

Direction of Flow

ENERGY SOURCES Pneumatic (Anyfluidpowersource)

Compressor (Fixeddisplacement)

Vacuum Pump (Fixeddisplacement)

Accumulator

PNEUMATIC SYMBOLS

VALVES Single Square (Unitforcontrollingflow.Containsinformationonportingandflowpaths.)

One Flow Path

Two Closed Ports

Two Flow Paths

Two Flow Paths & One Closed Port

Two Flow Paths with Cross Connection

One By-pass Flow Path & Two Closed Ports

Two External Ports

2-Position Envelope

3-Position Envelope

Two Distinct Positions & One Transitory (center) Position

2/2 Valve �Ports,�Positions

3/2 Valve 3Ports,�Positions

or

FLUID CONDITIONERS Basic Envelope (Filtersandlubricators)

Filter (Manualdrain)

Filter (Automaticdrain)

Lubricator(Lessdrain)

Lubricator (Manualdrain)

Air Dryer

Pressure Regulator (Adjustable,self-relieving)

Pressure Regulator (Adjustable,non-relieving)

VALVES (cont.)



4/3 Valve 4Ports,3Positions


ENERGY CONVERSION (cont.)

Cylinder Double Acting Singlerod

Cylinder Double Acting Doublerod

Cylinder Double Acting Singlefixedcushion

Cylinder Double Acting Twoadjustablecushions

Quick Acting Coupling

Quick Acting Coupling – With mechanicallyopenednon-returnvalve

Quick Acting Coupling – Notcoupled,withopenend

Quick Acting Coupling – Notcoupled;closedbyfreenon-returnvalve

Silencer

Air Motor Onedirectionalflow

Air Motor Twodirectionalflows

Release of Internal Pilot Pressure

Interior Control Path

Solenoid or Internal Pilot

Solenoid or External Pilot

Solenoid plus Internal Pilot

Two External Pilots

Solenoid & Pilot or Manual Override

Solenoid & Pilot or Manual Override and Pilot

Differential Pressure

ENERGY CONVERSION

Cylinder Springreturn

Cylinder Unspecifiedreturn

ACTUATORS and CONTROLS Detent – �PositionVerticallineindicatesflowposition.

Muscular Control

Push-button

Lever

Pedal or Treadle

Plunger or Position Indicator Pin

Spring

Roller

Roller - Oneway

SolenoidSinglewinding

Solenoid Twooppositewindings

Variable Solenoid Twooppositewindings

Pilot Pressure External

Pilot Pressure Internal

PNEUMATIC SYMBOLS


FLUID CONDUCTORS Working Line

Exhaust Line or Control Line

Lines Crossing

Lines Connected

Mechanical Connection (Shaft,Rod,etc.)

Fixed Restriction

Variable Restriction

Flexible Line

Plugged Port

Direction of Flow

ENERGY SOURCES Pneumatic (Anyfluidpowersource)

Compressor (Fixeddisplacement)

Vacuum Pump (Fixeddisplacement)

Accumulator

PNEUMATIC SYMBOLS

VALVES Single Square (Unitforcontrollingflow.Containsinformationonportingandflowpaths.)

One Flow Path

Two Closed Ports

Two Flow Paths

Two Flow Paths & One Closed Port

Two Flow Paths with Cross Connection

One By-pass Flow Path & Two Closed Ports

Two External Ports

2-Position Envelope

3-Position Envelope

Two Distinct Positions & One Transitory (center) Position

2/2 Valve �Ports,�Positions


or

FLUID CONDITIONERS Basic Envelope (Filtersandlubricators)

Filter (Manualdrain)

Filter (Automaticdrain)

Lubricator(Lessdrain)

Lubricator (Manualdrain)

Air Dryer

Pressure Regulator (Adjustable,self-relieving)

Pressure Regulator (Adjustable,non-relieving)

VALVES (cont.)





ENERGY CONVERSION (cont.)

Cylinder Double Acting Singlerod

Cylinder Double Acting Doublerod

Cylinder Double Acting Singlefixedcushion

Cylinder Double Acting Twoadjustablecushions

Quick Acting Coupling

Quick Acting Coupling – With mechanicallyopenednon-returnvalve

Quick Acting Coupling – Notcoupled,withopenend

Quick Acting Coupling – Notcoupled;closedbyfreenon-returnvalve

Silencer

Air Motor Onedirectionalflow

Air Motor Twodirectionalflows

Release of Internal Pilot Pressure

Interior Control Path

Solenoid or Internal Pilot

Solenoid or External Pilot

Solenoid plus Internal Pilot

Two External Pilots

Solenoid & Pilot or Manual Override

Solenoid & Pilot or Manual Override and Pilot

Differential Pressure

ENERGY CONVERSION

Cylinder Springreturn

Cylinder Unspecifiedreturn

ACTUATORS and CONTROLS Detent – �PositionVerticallineindicatesflowposition.

Muscular Control

Push-button

Lever

Pedal or Treadle

Plunger or Position Indicator Pin

Spring

Roller

Roller - Oneway

SolenoidSinglewinding

Solenoid Twooppositewindings

Variable Solenoid Twooppositewindings

Pilot Pressure External

Pilot Pressure Internal

PNEUMATIC SYMBOLS

14 ROSS CONTROLS®

SPECIAL PURPOSE VALVES Check ValveNon-return

Check Valve Springloaded

Flow Control Valve

Shuttle Valve

Sequence Valve

Shutoff Valve

Pilot Control Identification. The following numbersare used on symbols for pilot control or control portidentification.Whenanelectricalorpneumaticsignalisappliedtothecontrolorport,thefollowingconditionsresult:

10 Inlet1isclosed. 12 Inlet1isconnectedtooutlet�. 14 Inlet1isconnectedtooutlet4.

Use of some of the above controls are shown in thefollowingexamples.

Example 1. �/� (� port, � position) normally open,springreturnvalve.

Valvenotactuated.

Valveactuatedbypneumaticsignalappliedtoport10.

MEASURING INSTRUMENTS and SWITCHES Pressure Gauge

Pressure Actuated Electric Switch

Flow Gauge

PNEUMATIC SYMBOLS – PORT IDENTIFICATION

TheportmarkingsonROSSvalvesarethesameasthoseshownonthevalvesymbolsinROSSliterature.Mainportsareidentifiedbynumbers,exceptforSAEvalveswhichcontinuetouselettersforidentification.

Oldervalvesmaynothavenumericalportmarkings.Thecorrespondence between the older markings and thecurrentnumericalmarkingsisshownbelow.

Current Port Marking Previous Port Marking

1 IN,P 2 OUT1,OUTA,CYL1,CYLA 3 EXH,EA,R 4 OUT�,OUTB,CYL�,CYLB 5 EXH,EB,S 12 CA 14 CB

Main Port Identification. Numbers1through5areusedformainportidentificationasfollows:

1 Normalinletport. 2 Normaloutletport. 2 & 4 Normaloutletportswheretwoare provided. 3 Normalexhaustport. 3 & 5 Normalexhaustportswheretwoare provided.

PORT IDENTIFICATION

10

2

1

10

2

1

Example 2. 3/� (3 port, � position) normally closed,springreturnvalve.

Valvenotactuated.

Valveactuatedbyelectricalsignalappliedtocontrol1�.

Example 3. 4/�(4port,�position)springreturnvalve.

Valvenotactuated.

Valveactuatedbypneumaticsignalappliedtocontrol14.

PORT IDENTIFICATION – CONVERSION FACTORS

Example 4. 5/3 (5 port, 3 position) closed center,springcenteredvalve.

Valveinnon-actuatedcenterposition.


Valveactuatedbyelectricalsignalappliedtocontrol14.

Auxiliary Ports for Pilot Operators

Port Function

X Externalpilotsupplyport

X1 Y2 Y3 Exhaustportforsolenoidpilot Y4

Example:

24

1 35

14 12

24

1 35

14 12

24

1 35

14 12

13

2

12

13

2

12

13

24

14

13

24

14

CONVERSION FACTORS

U.S. to Metric ConversionFrom To Multiply By

inches...................millimeters................................�5.40

feet........................meters....................................0.3048

miles.....................kilometers.................................1.609

squarefeet............squaremeters......................0.09�90

cubicfeet..............cubicmeters.........................0.0�83�

cubicfeet..............liters..........................................�8.3�

gallon....................liters..........................................3.785

pounds..................kilograms................................0.4536

lb/in�(psi)..............bar........................................0.06895

ft3/min....................liters/second(l/s)....................0.4718

Metric to U.S. ConversionFrom To Multiply By

millimeters............inches................................... 0.03937

meters...................feet........................................... 3.�81

kilometers.............miles....................................... 0.6�14

squaremeters.......squarefeet............................... 10.76

cubicmeters.........cubicfeet.................................. 35.30

liters......................cubicfeet.............................. 0.03531

liters......................gallons.................................... 0.�64�

kilograms..............pounds...................................... �.�05

bar........................lb/in�.......................................... 14.50

liters/second(l/s)..ft3/min....................................... �.1�0

13

24

14

XY4

}}


SPECIAL PURPOSE VALVES Check ValveNon-return

Check Valve Springloaded

Flow Control Valve

Shuttle Valve

Sequence Valve

Shutoff Valve

Pilot Control Identification. The following numbersare used on symbols for pilot control or control portidentification.Whenanelectricalorpneumaticsignalisappliedtothecontrolorport,thefollowingconditionsresult:

10 Inlet1isclosed. 12 Inlet1isconnectedtooutlet�. 14 Inlet1isconnectedtooutlet4.

Use of some of the above controls are shown in thefollowingexamples.

Example 1. �/� (� port, � position) normally open,springreturnvalve.

Valvenotactuated.

Valveactuatedbypneumaticsignalappliedtoport10.

MEASURING INSTRUMENTS and SWITCHES Pressure Gauge

Pressure Actuated Electric Switch

Flow Gauge

PNEUMATIC SYMBOLS – PORT IDENTIFICATION

TheportmarkingsonROSSvalvesarethesameasthoseshownonthevalvesymbolsinROSSliterature.Mainportsareidentifiedbynumbers,exceptforSAEvalveswhichcontinuetouselettersforidentification.

Oldervalvesmaynothavenumericalportmarkings.Thecorrespondence between the older markings and thecurrentnumericalmarkingsisshownbelow.

Current Port Marking Previous Port Marking

1 IN,P 2 OUT1,OUTA,CYL1,CYLA 3 EXH,EA,R 4 OUT�,OUTB,CYL�,CYLB 5 EXH,EB,S 12 CA 14 CB

Main Port Identification. Numbers1through5areusedformainportidentificationasfollows:

1 Normalinletport. 2 Normaloutletport. 2 & 4 Normaloutletportswheretwoare provided. 3 Normalexhaustport. 3 & 5 Normalexhaustportswheretwoare provided.

PORT IDENTIFICATION

10

2

1

10

2

1

Example 2. 3/� (3 port, � position) normally closed,springreturnvalve.

Valvenotactuated.


Example 3. 4/�(4port,�position)springreturnvalve.

Valvenotactuated.

Valveactuatedbypneumaticsignalappliedtocontrol14.

PORT IDENTIFICATION – CONVERSION FACTORS

Example 4. 5/3 (5 port, 3 position) closed center,springcenteredvalve.

Valveinnon-actuatedcenterposition.


Valveactuatedbyelectricalsignalappliedtocontrol14.

Auxiliary Ports for Pilot Operators

Port Function

X Externalpilotsupplyport

X1 Y2 Y3 Exhaustportforsolenoidpilot Y4

Example:

24

1 35

14 12

24

1 35

14 12

24

1 35

14 12

13

2

12

13

2

12

13

24

14

13

24

14

CONVERSION FACTORS

U.S. to Metric ConversionFrom To Multiply By

inches...................millimeters................................�5.40

feet........................meters....................................0.3048

miles.....................kilometers.................................1.609

squarefeet............squaremeters......................0.09�90

cubicfeet..............cubicmeters.........................0.0�83�

cubicfeet..............liters..........................................�8.3�

gallon....................liters..........................................3.785

pounds..................kilograms................................0.4536

lb/in�(psi)..............bar........................................0.06895

ft3/min....................liters/second(l/s)....................0.4718

Metric to U.S. ConversionFrom To Multiply By

millimeters............inches................................... 0.03937

meters...................feet........................................... 3.�81

kilometers.............miles....................................... 0.6�14

squaremeters.......squarefeet............................... 10.76

cubicmeters.........cubicfeet.................................. 35.30

liters......................cubicfeet.............................. 0.03531

liters......................gallons.................................... 0.�64�

kilograms..............pounds...................................... �.�05

bar........................lb/in�.......................................... 14.50

liters/second(l/s)..ft3/min....................................... �.1�0

13

24

14

XY4

}}

WarrantyProductsmanufacturedbyROSSarewarrantedtobefreeofdefectsinmaterialandworkmanshipforaperiodofoneyearfromthedateofpurchase.ROSS’obligationunderthiswarrantyislimitedtorepairorreplacementoftheproductorrefundofthepurchasepricepaidsolelyatthediscretionofROSSandprovidedsuchproductisreturnedtoROSSfreightprepaidanduponexaminationbyROSSsuchproductisfoundtobedefective.Thiswarrantyshallbevoidintheeventthatproducthasbeensubjecttomisuse,misapplication,impropermaintenance,modificationortampering. THEWARRANTYEXPRESSEDABOVE IS INLIEUOFANDEXCLUSIVEOFALLOTHERWARRANTIESANDROSSEXPRESSLYDISCLAIMSALLOTHER WARRANTIES EITHER EXPRESSED OR IMPLIED WITH RESPECT TO MERCHANTABILITY OR FITNESSFORAPARTICULARPURPOSE.ROSSMAKESNOWARRANTYWITHRESPECTTOITSPRODUCTSMEETINGTHEPROVISIONSOFANYGOVERNMENTALOCCUPATIONALSAFETYAND/ORHEALTHLAWSORREGULATIONS.INNOEVENTSHALLROSSBELIABLETOPURCHASER,USER,THEIREMPLOYEESOROTHERSFORINCIDENTALORCONSEQUENTIALDAMAGESWHICHMAYRESULTFROMABREACHOFTHEWARRANTYDESCRIBEDABOVEORTHEUSEORMISUSEOFTHEPRODUCTS.NOSTATEMENTOFANYREPRESENTATIVEOREMPLOYEEOFROSSSHALLEXTENDTHELIABILITYOFROSSASSETFORTHHEREIN.

Your local ROSS distributor is:

GLOBAL Reach with a LOCAL Touchsm

ROSS CONTROLS®

Troy, MI., U.S.A.Telephone: + 1-248-764-1800Fax: + 1-248-764-1850In the United States:Safety Department: 1-248-764-1816Customer Service: 1-800-GET ROSS (438-7677)Technical Service: 1-888-TEK-ROSS (835-7677)www.rosscontrols.com

ROSS UK Ltd.Birmingham, United KingdomTelephone: + 44-121-559-4900Fax: + 44-121-559-5309Email: [email protected]

ROSS SOUTH AMERICA Ltda.São Paulo, Brazil CEP 09725-020Telephone: + 55-11-4335-2200Fax: + 55-11-4335-3888Email: [email protected]

ROSS EUROPA® GmbHLangen, GermanyTelephone: + 49-6103-7597-0Fax: + 49-6103-74694Email: [email protected]

ROSS ASIA® K.K.Kanagawa, JapanTelephone: + 81-427-78-7251Fax: + 81-427-78-7256www.rossasia.co.jp

ROSS CONTROLS (CHINA) LtdShanghai, ChinaTelephone: + 86-21-6915-7951 Fax: + 86-21-6915-7960Email: [email protected]

ROSS CONTROLS® INDIA Pvt. Ltd.Chennai, IndiaTelephone: + 91-44-2624-9040Fax: + 91-44-2625-8730Email: [email protected]

DIMAFLUID s.a.s.Saint Ouen, FranceTelephone: + 33-01-49-45-65-65Fax: + 33-01-49-45-65-30Email: [email protected]

FormA1007� © 2007 ROSS CONTROLS®. All Rights Reserved.PrintedintheU.S.A.-Rev.05/07

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