30678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 251MASTER ➁Process DiagramsOBJECTIVESAfter studying this chapter, the student will be able to:•Review process diagram symbols.•Describe the use of process diagrams and the information they contain.•Draw a process flow diagram.•Draw a process and instrument drawing.•Describe the various process equipment relationships.25130678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 252MASTER ➁Chapter 12●Process DiagramsKey TermsElectrical drawings—symbols and diagrams that depict an electrical process.Elevation drawings—a graphical representation that shows the location of process equipment inrelation to existing structures and ground level.Equipment location drawings—show the exact floor plan for location of equipment in relation tothe plan’s physical boundaries.Flow diagram—a simplified sketch that uses symbols to identify instruments and vessels and todescribe the primary flow path through a unit.Foundation drawings—concrete, wire mesh, and steel specifications that identify width, depth,and thickness of footings, support beams, and foundation.Legends—a document used to define symbols, abbreviations, prefixes, and specialized equipment.Process and instrument drawing (P&ID)—a complex diagram that uses process symbols todescribe a process unit;also called piping and instrumentation drawing.Types of Process DiagramsProcess diagrams can be broken down into two major categories:processflow diagrams(PFDs) and process and instrument drawings (P&IDs),sometimes called piping and instrumentation drawings.A flow diagram is asimple illustration that uses process symbols to describe the primary flowpath through a unit.A process flow diagram provides a quick snapshot ofthe operating unit.Flow diagrams include all primary equipment and flows.A technician can use this document to trace the primary flow of chemicalsthrough the unit.Secondary or minor flows are not included.Complex con-trol loops and instrumentation are not included.The flow diagram is usedfor visitor information and new employee training.A process and instrument drawing is more complex.The P&ID includes agraphic representation of the equipment, piping, and instrumentation.Mod-ern process control can be clearly inserted into the drawing to provide aprocess technician with a complete picture of electronic and instrumentsystems.Process operators can look at their process and see how the en-gineering department has automated the unit.Pressure, temperature, flow,and level control loops are all included on the unit P&ID.Basic Instrument SymbolsProcess technicians use P&IDs to identify all of the equipment, instru-ments, and piping found in their units.New technicians use these drawings25230678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 253MASTER ➁Basic Instrument SymbolsVALVESSHGateNeedleValveFour-WayAngle Diaphragm ManualOperatedGaugeSolenoidHydraulicBackBackValveValvePressurePneumaticCLOSEDRegulatorOperatedPressureRegulatorGlobeThree-WayValveButterflyValveMPneumaticOperatedBallButterfly ValveReliefCheck ValvePlugBleederValvesOrificeMotorRotameterPRVSafetyPSVCOMPRESSORSPUMPS & TURBINEReciprocatingCompressor &Centrifugal CentrifugalVacuumCompressorSilencersCompressorPumpsPumpVerticalTRotaryLiquid RingCentrifugal CompressorScrew PumpTurbineCompressorCompressor(Turbine Driven)Gear PumpHEAT EXCHANGERSLINE SYMBOLSFuture EquipmentMajor ProcessHairpin ExchangerU-TubeHeat ExchangerShell & Tube Heat ExchangerMinor ProcessPneumaticHydraulicLLLSingle PassCapillary TubingXXXXXElectromagnetic SignalXHeat ExchangerReboilerHeaterCondenserElectricVESSELSTITemp IndicatorDrum or CondenserTTTemp TransmitterMixerTRTemp RecorderLILevel IndicatorLTLevel TransmitterTankLCLevel ControllerMixing ReactorForced-Draft Cooling TowerFIFlow IndicatorFTFlow TransmitterFRFlow RecorderPIPressure IndicatorBinTowerTowerPTPressure TransmitterFurnacewith PackingPRCInduced-Draft Cooling TowerPressure Recording ControllerFigure 12.1aProcess and Instrument Symbols25330678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 254Chapter 12●254MASTER ➁Process DiagramsTITemp IndicatorFIFlow IndicatorIPTransducerTTTemp TransmitterFTFlow TransmitterPICPressure Indicating105ControllerTRTemp RecorderFRFlow RecorderPRCPressure Recording40ControllerTCTemp ControllerFCFlow ControllerLALevel Alarm25LILevel IndicatorPIPressure IndicatorFEFlow ElementLTPT65Level Transmitter55Pressure TransmitterTETemperature ElementLRPR65Level Recorder55Pressure RecorderLGLevel GaugeLCPC65Level Controller55Pressure ControllerATAnalyzer TransmitterVariable BeingMeasuredWhat It DoesInstrumentF I C55Field MountedRemote LocationRemote LocationControl Loop(board mounted)(behind control panel)Figure 12.1bProcess and Instrument Symbols (continued)during their initial training period.Knowing and recognizing these symbolsis important for a new technician.The chemical processing industry has as-signed a symbol for each type of valve, pump, compressor, steam turbine,heat exchanger, cooling tower, basic instrumentation, reactor, distillationcolumn, furnace, and boiler (Figure 12.1).There are symbols to representmajor and minor process lines and pneumatic, hydraulic, or electric lines,and there is a wide variety of electrical symbols.Flow DiagramsNew technicians are required to study a simple flow diagram of their as-signed operating system.Process flow diagrams typically include the majorequipment and piping path the process takes through the unit.As operatorslearn more about symbols and diagrams, they graduate to the much morecomplex P&IDs.30678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 255MASTER ➁Cooling TowerVacuum PumpProductTank1DrumFurnaceFeed TankColumnProductReactorsTank2Bottoms TankBoilerFigure 12.2Process Flow Diagram (PFD)Some symbols are common among plants;others differ from plant to plant.Some standardization of process symbols and diagrams is taking place.The symbols used in this chapter reflect a wide variety of petrochemicaland refinery operations.Figure 12.2 is a PFD that shows the basic relationships and flow pathsfound in a process unit.It is easier to understand a simple flow diagram if itis broken down into sections:feed, preheating, the process, and the finalproducts.This simple left-to-right approach allows a technician to identifywhere the process starts and where it will eventually end.The feed sectionincludes the feed tanks, mixers, piping, and valves.In the second step, theprocess flow is gradually heated for processing.This section includes heatexchangers and furnaces.In the third section, the process is included.Typ-ical examples found in the process section could include distillationcolumns or reactors.The process area is a complex collection of equipmentthat works together to produce products that will be sent to the final section.Flow Diagrams25530678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 256MASTER ➁Chapter 12●Process DiagramsProcess and Instrument DrawingsA P&ID is a complex representation of the various units found in a plant(Figure 12.3).It is used by people in a variety of crafts.The primary usersof the document after plant startup are process technicians and instrumentand electrical, mechanical, safety, and engineering personnel.In order to read a P&ID, the technician needs an understanding of theequipment, instrumentation, and technology.The next step in using a P&IDis to memorize your plant’s process symbol list.This information can befound on the process legend.Process and instrument drawings have a va-riety of elements, including flow diagrams, equipment locations, elevationplans, electrical layouts, loop diagrams, title blocks and legends,and foun-dation drawings.The entire P&ID provides a three-dimensional look at thevarious operating units in a plant.Process LegendThe process legend (Figure 12.4) provides the information needed to inter-pret and read the P&ID.Process legends are found at the front of the P&ID.The legend includes information about piping, instrument and equipmentP-12CT-105V-2V-3PCI/PP-13PTPCVD-105LTLCI/PTk-12F-105P-14Tk-10C-105V-4V-5Rx-105FCI/PV-6FTTTTCTk-14V-1LTTETTTCI/PFCVI/PRx-106P-10LCP-15I/PEX-105Tk-16P-11V-7B-105Figure 12.3Process and Instrument Diagram (P&ID)25630678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 257MASTER ➁Process and Instrument DrawingsVALVE SYMBOLSEQUIPMENT CONT.LINE SYMBOLSFuture EquipmentGateBallMajor ProcessBleederValvePneumaticManualOperatedValvesValveMinor ProcessPlugPneumaticPneumaticGlobeAngle ValveKnife ValveButterflyINDUCED DRAFTHydraulicLLLCrossflowSCapillary TubingXXXXReliefPinch ValveValveMechanical Link••••SAFETY (Gases)Solenoid ValveCLOSEDCheckStop CheckElectromagnetic, SonicValveOptical, NuclearDiaphragmThree-WayElectricFour-WayValveEQUIPMENT SYMBOLSNATURAL DRAFTConnecting LineCounterflowNon-Connecting LineNon-Connecting LineVacuumJacketed or Double ContainmentHorizontalPumpSoftware or Data LinkVerticalSump PumpINSTRUMENT SYMBOLSOrificeBOILERTITemp. IndicatorCentrifugal FIFlow IndicatorRotameterTTTemp. TransmitterFTFlow TransmitterGearPumpPositiveRotary ScrewTRTemp. RecorderFRFlow RecorderDisplacementFURNACECompressorTCTemp. ControllerGaugeFCFlow ControllerReciprocatingLILevel IndicatorPIPressure IndicatorPumpSinglePassDemisterLTLevel TransmitterPT55Pressure TransmitterScrew PumpSpray65ChimneyNozzleLRPRProgressive Cavity65Level Recorder55Pressure RecorderTwo PassPackedSectionLC65Level ControllerPC55Pressure ControllerFEFlow ElementIPTransducerDraw OffCCGenericTETemperature ElementPICPressure IndicatingTrayManway105ControllerDouble-PipePlate and FrameLGLevel GaugePRCPressure RecordingHeat ExchangerSpiral Heat Heat Exchanger40ControllerExchangerVortexBreakerATAnalyzer TransmitterLA25Level AlarmPAir Cooled ExchangerC(Louvers Optional)EDrumAPPROVED10-6-99Dome RoofSphereDATETankGENERAL LEGENDCondenserDISTILLATION UNITCone RoofDRAWING NUMBERTankInternal FloatingRoof TankOO6543REVISION 1PAGE 1 OF 30HeaterPREFIXESABBREVIATIONSCW- cooling waterRX- reactorD- drumTK-tankP- pumpMU- makeupUT- utilitiesC- columnF- furnaceV- valveFW- feed waterCA- chemical additionCT- cooling towerEX- exchangerSE- sewerIA- instrument airFigure 12.4Process Legend25730678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 258Chapter 12●258MASTER ➁Process DiagramsS4\"EW18\"Remesh12\"N2' x ' x 18\"Load-BearingRebar in BeamAll Beams32' 0\"RemeshRemeshOver Plastic6' 0\"6-8-10 Method10' 0\"28' 0\"908' 0\"28' 0\"' 0\"Estimating Materials: cu. yds. = width x length x thickness27Figure 12.5Foundationsymbols, abbreviations, unit name, drawing number, revision number,approvals, and company prefixes.Because symbol and diagram standard-ization is not complete, many companies use their own symbols in unitdrawings.Unique and unusual equipment will also require a modified sym-bols file.Foundation DrawingThe construction crew pouring the footers, beams, and foundation usesfoundation drawings (Figure 12.5).Concrete and steel specifications aredesigned to support equipment, integrate underground piping, and providesupport for exterior and interior walls.Process technicians do not typicallyuse foundation drawings, but these drawings are useful when questionsarise about piping that disappears under the ground and when new equip-ment is being added.Elevation DrawingElevation drawings(Figure 12.6) show the location of process equipmentinrelation to existing structures and ground level.In a multistory structure,the elevation drawing provides the technician with information about30678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 259MASTER ➁Process and Instrument DrawingsRX-300TK-300C-300EL-40' 0\"D-56EL28' 0\"RX-105EL 16' 0\"TK-105TK-200RX-106equipment location.This information is important for making rounds, check-ing equipment, developing checklists, catching samples, and performingstartups and shutdowns.Electrical DrawingElectrical drawings(Figure 12.7) include symbols and diagrams that de-pict an electrical system.Electrical drawings show unit electricians wherepower transmission lines run and places where power is stepped down orup for operational purposes.A process technician typically traces power to the unit from a motor controlcenter (MCC).The primary components of an electrical system are theMCC, motors, transformers, breakers, fuses, switchgears, starters, andswitches.Specific safety rules are attached to the operation of electricalsystems.The primary safety system is the isolation of hazardous energy“lock-out, tag-out.”Process technicians are required to have training in thisarea.Figure 12.7 shows the basic symbols and flow path associated withan electrical drawing.Electrical lines are typically run in cable trays toswitches, motors, ammeters, substations, and control rooms.A transformer is a device used by industry to convert high voltage to lowvoltage.The electric department always handles problems with transform-ers.Electric breakers are designed to interrupt current flow if design condi-tions are exceeded.Breakers are not switches and should not be turned onFigure 12.6Elevation Drawing25930678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 260MASTER ➁Chapter 12●Process Diagrams69,000 Volts69 KVMAINTRANSFORMERVAAs51Vs2713,200 V13.2 KV13, 800 V13.8 KV2,300 V2.3 KVBOILERGenerator480V BUS MAIN POWER DISTRIBUTIONSteamTurbineMCC #12.3 KV or480 VoltsELECTRIC POWER PLANTMotorMotorStarterStarterMMMotorOnOffMMotorFuseMCCMotor Control CenterVVoltmeter: measures voltageVsVoltmeter Switch27Under Voltage RelayCurrent Transformer: reduces high voltage to instrumentation.AAmmeter: measures electric currentAsAmmeter switch50Transformer Overcurrent Relay (Instantaneous)Potential Transforming Symbol51Transformer Overcurrent Relay (Time delay)Power Transformer: reduces high voltageCircuit Breaker: a protective devicethat interrupts current flow through anSwitchelectric circuitMotor Circuit ContactsFigure 12.7Electrical Drawing26030678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 261MASTER ➁Process and Instrument Drawingsor off.If a tripping problem occurs, the technician should call for an electri-cian.Fuses are devices designed to protect equipment from excess cur-rent.A thin strip of metal will melt if design specifications are exceeded.During operational rounds, technicians check the ammeters inside theMCC for current flow to their electrical systems.Voltmeters, electricaldevices used to monitor voltage in an electrical system, are also checkedduring routine rounds.Equipment Location DrawingEquipment location drawings(plot plans) show the exact location ofequipment in relation to the plant’s physical boundaries (Figure 12.8).Oneof themost difficult concepts to explain to a new process technician is thescope and size of modern chemical processing.Most chemical plants andrefineries closely resemble small cities;they have well-defined blocks andareas connected by a highway of piping and equipment.Equipment loca-tion drawings provide information about the neighborhood.Loop DiagramsA loop diagram traces all instrument connections between the field instru-ment and the control room panel.This includes instrument air lines, wiringconnections at field junction boxes, and control room panels and frontconnections.Electrical One-Line DiagramsLike the piping in process systems, the wiring in a unit follows a path.Electri-cal diagrams show a flow path for distributing power throughout the unit andTK-1TK-2\"0 '8TK-3TK-4P-10020' 0\"\"18' 0\"8' 0\"P-2000 '02\"\"0TK-100D-2000 '6EX-200 '0218' 0\"TK-200P-500AC-2008' 0\"P-201TK-300TK-400EX-202\"20' 0\"0 '0P-3001P-40016' 0\"Figure 12.8Equipment Location26130678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 262MASTER ➁Chapter 12●Process DiagramsFigure 12.9Piping Symbols262to all electrical equipment.These diagrams show the different voltage levelsin the unit, electrical equipment such as transformers, circuit breakers, fuses,and motors and horsepower required.It also includes start/stop switches,emergency circuits, and motor control centers.Process technicians can usethese diagrams to trace a system from the power source to the load.Review of Basic and Specialized SymbolsPiping and ValvesEach plant will have a standardized file for their piping symbols.Processtechnicians should carefully review the piping symbols for major and minorflows;electric, pneumatic, capillary, and hydraulic elements;and futureequipment (Figure 12.9).The major flow path through a unit illustrates theY-type StrainerRSRemovable SpoolFlexible HoseDuplex StrainerExpansion JointBasket StrainerXXXBreatherDDetonation ArrestorVent CoverIn-Line MixerFFlame ArrestorSIn-Line SilencerSVent SilencerTSteam TrapDiverter ValveDSDesuperheaterRotary ValveEjector / EductorPulsation DampenerExhaust HeadFlangeFuture EquipmentElectromagnetic, SonicMajor ProcessOptical, NuclearMinor ProcessElectricConnecting LinePneumaticNon-Connecting LineLLLHydraulicNon-Connecting LineXXXXCapillary TubingJacketed or Double Containment••••Mechanical LinkSoftware or Data Link30678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 263MASTER ➁Review of Basic and Specialized Symbolscritical areas a new technician should concentrate on.A variety of othersymbols are included on the piping.These include valves (Figure 12.10),strainers, filters, flanges, spool pieces, insulation, piping size, pressure rat-ing, material codes, and steam traps.Pumps and TanksPumps and tanks come in a variety of designs and shapes.Common pumpand tank symbols are shown on Figure 12.11.Compressors,Steam Turbines,and MotorsBecause compressors and pumps share a common set of operating prin-ciples and are classified as dynamic or positive displacement, the sym-bolsfor compressors may closely resemble those for pumps (compareGATE VALVESMHGateManualOperatedBleederValvePneumaticMotorHydraulicValveValvesGLOBE VALVESMHAngle MGlobeValvePneumaticMotorHydraulicNeedlePneumaticMotorBALL VALVESHPLUG VALVESMBallBallMotor orPlugHydraulicPlugMotor orHydraulicBUTTERFLY VALVESMSButterflyButterflyButterflyMotor orPneumaticSolenoid ValveHydraulicOperatedCLOSEDDIAPHRAGM VALVESCHECK VALVESMDiaphragmMotorCheckCheckValveValveStop CheckSAFETY (Gases)RELIEF (Liquids)Four-WayThree-WayValveReliefValveKnife ValvePinch ValveGaugeRotameterOrificeFigure 12.10Valves26330678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 2Chapter 12●2MASTER ➁Process DiagramsCENTRIFUGAL PUMPSPOSITIVE DISPLACEMENT PUMPSPositive DisplacementPositiveDisplacementVerticalProgressive CavityHorizontalScrew PumpGearPumpVerticalScrew PumpVerticalSump PumpVacuum PumpVertical CanPumpReciprocating PumpSTORAGE SYMBOLSDome RoofOpen TopTankTankBinTankTankInternal FloatingDouble WallRoof TankTankCone RoofDrumTankSphereOnion TankExternal FloatingRoofFigure 12.11Pumps and TanksFigures12.11 and 12.12).In most cases, the compressor symbol is slightlylarger than the pump symbol.In the multistage, centrifugal compressors, the narrowing of the symbol fromleft to right denotes compression of the gas before it is released.This is insharp contrast to the steam turbine symbol, which illustrates the opposite ef-fect as the steam expands while passing over the rotor.Modern P&IDs showthe motor symbol connected to the driven equipment.This equipment maybe a pump, compressor, mixer, or generator.Figure 12.12 illustrates thestandardized symbols for compressors, steam turbines, and motors.Heat Exchangers and Cooling TowersHeat exchangers and cooling towers are two types of industrial equipmentthat share a unique relationship.A heat exchanger is a device used to30678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 265MASTER ➁Review of Basic and Specialized SymbolsCENTRIFUGAL COMPRESSORSPD COMPRESSORSTCentrifugal Centrifugal CompressorReciprocatingCompressor(Turbine Driven)CompressorRotoryRotaryCompressor Compressor& SilencersCentrifugalRotary ScrewCompressorLiquid RingCompressorCentrifugalVacuumBlowerPositiveDisplacementBlowerAxial CompressorReciprocating CompressorSTEAM TURBINE MOTORSAgitator or MixerTurbine DriverDoubleflow TurbineMotorDiesel MotorFigure 12.12Compressors,Steam Turbines,and Motorstransfer heat energy between two process flows.The cooling tower per-forms a similar function, but cooling towers and heat exchangers use dif-ferent scientific principles to operate.Heat exchangers transfer heat energythrough conductive and convective heat transfer, whereas cooling towerstransfer heat energy to the outside air through the principle of evaporation.Figures 12.13 and 12.14 illustrate the standard symbols used for heatexchangers and cooling towers.Thesymbolforaheatexchangerclearlyillustratestheflowsthroughthedevice.Itisimportantforaprocesstechniciantobeabletorecog-nizetheshellinletandoutletandthetubeinletandoutletflowpaths.Aheatexchangerwithanarrowdrawnthroughthebodyillustrateswhetherthetubesideflowisbeingusedtoheatorcooltheshellsidefluid.Thedownwarddirectionindicatesheating;theupwarddirectionil-lustratescooling.26530678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 266MASTER ➁Chapter 12●Process DiagramsFigure 12.13Heat ExchangersFigure 12.14Cooling Towers266Plate and FrameHeat ExchangerHairpin ExchangerAir Cooled ExchangerU-Tube(Louvers Optional)Heat ExchangerDouble-PipeSingle PassHeat ExchangerHeat ExchangerCCSpiral Heat ExchangerReboilerHeaterCondenserShell and Tube Heat ExchangerINDUCED DRAFTCrossflowFORCED DRAFTCounterflowHYPERBOLICNATURAL DRAFTChimney TowerCounterflow30678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 267MASTER ➁Review of Basic and Specialized SymbolsFurnaceBoilerThe symbol for a cooling tower is designed to resemble the actual deviceinthe process unit.Cooled product flows out of the bottom of the tower andto the processing units.Hot water returns to a point located above the fill.The symbol will not show all of the various components of the cooling towersystem, but it will provide a technician with a good foundation in coolingtower operation and enough information to clearly see the process.Furnaces and BoilersThe standard symbols file for furnaces and boilers is shown in Fig-ure12.15.If a proprietary process includes several types of equipment nottypically found on a standard symbol file, the designer will draw the deviceas it visually appears in the unit.Distillation ColumnsDistillation columns come in two basic designs, plate and packed (Fig-ure12.16).Flow arrangements vary from process to process.The sym-bols allow the technician to identify primary and secondary flow paths.Distillation is a process designed to separate the various components ina mixture by their boiling points.(See Chapter 15.) A distillation column isthe central component of a much larger system.This system typically in-cludes all of the equipment symbols found in this chapter.Plate distillationcolumns include sieve trays, valve trays, and bubble-cap trays.Packedcolumns are filled with packing material, rings, saddles, sulzer, androsette.ReactorsReactors(Figure12.17)arestationaryvesselsandcanbeclassifiedasbatch,semibatch,orcontinuous.Areactorisdesignedtoallowchemi-calstomixtogetherunderspecificconditionstomakechemicalbonds,breakchemicalbonds,ormakeandbreakchemicalbondstoformnewproducts.Figure 12.15Furnace and Boiler26730678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 268MASTER ➁Chapter 12●Process DiagramsFigure 12.16Distillation Symbols268PLATE TOWERPACKED TOWERBubble-cap, Sieve, ValveSaddle, Ring, Sulzer, RosetteSingle PassDemisterSpray NozzleChimneyTwo PassPacked SectionDraw OffGeneric TrayManwayVortex BreakerSources of InformationforProcessTechniciansInformation used by process technicians comes from a variety of sources.Some of these sources are:•Operating training manuals•Process descriptions•Process control manuals•Equipment summaries•Safety, health, and environment regulations•Operating procedures•Startup and shutdown procedures30678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 269HydrocrackingHydrodesulfurizationReformerFluid CatalyticFluid CokingTubularFluidizedCrackingReactorReactorMixing ReactorAlkylation•Emergency procedures•Process diagrams•Technical data books•Detailed equipment vendor informationSummaryProcess flow diagrams (PFDs) and process and instrument drawings(P&IDs) are used to outline or explain the complex flows, equipment, in-strumentation, electronics, elevations, and foundations that exist in aprocess unit.A PFD is a simple flow diagram that describes the primaryflow path through a unit.A P&ID is a complex representation of the variousunits found in a plant.Standardized symbols and diagrams have beendeveloped for most pieces of industrial equipment, process flows, andinstrumentation.MASTER ➁SummaryFigure 12.17Reactor Symbols26930678_12_ch12_p251-270.qxd 06/09/2006 11:14 Page 270MASTER ➁Chapter 12●Process DiagramsReview Questions1.Describe a process flow diagram and a process and instrument drawing.2.Draw the symbols for a gate, globe, and automatic valve.3.Draw the symbols for a centrifugal pump and positive displacement pump.4.Draw the symbols for a blower and a reciprocating compressor.5.Draw the symbols for a steam turbine and centrifugal compressor.6.Draw the symbols for a heat exchanger and a cooling tower.7.Draw the symbols for a packed distillation column and plate distillation column.8.Draw the symbols for a furnace and a boiler.9.Draw a simple process flow diagram using the symbols from questions 2–8.10.What information is obtained from a loop diagram?11.What information is available on electrical one-line diagrams?12.What information is contained on a plot plan drawing?270
