PMI培訓(xùn)資料：汽輪機(jī)1

汽輪機(jī)

steamturbine汽輪機(jī)在石油化工廠的作用Theapplicationofsteamturbineinpetrochemicalplant汽輪機(jī)是將蒸汽的熱能轉(zhuǎn)換成機(jī)械功的旋轉(zhuǎn)式動(dòng)力機(jī)械convertedintoshaftrotation，汽輪機(jī)具有功率大、轉(zhuǎn)速高、經(jīng)濟(jì)性好等顯著優(yōu)點(diǎn)，因此被廣泛用于電力、冶金，石油化工等行業(yè)，作為原動(dòng)機(jī)來(lái)驅(qū)動(dòng)發(fā)電機(jī)、壓縮機(jī)、鼓風(fēng)機(jī)、水泵等工作機(jī)械。

A

steamturbineisarotationtypedrivingmachinewhichconvertthermalenergy

ofsteamintomechanicalwork.Steamturbineshavesignificantadvantagessuchasgreatpower,highspeedandgoodeconomy.Theyarewidelyusedinpower,metallurgyandpetrochemicalindustryfordrivinggenerators,compressors,blowersandpumps.A

steamturbine

isadevicethatextractsthermal

energy

frompressurized

steam

andusesittodo

mechanicalwork

onarotatingoutputshaft.汽輪機(jī)的分類Typesofsteamturbine按作用原理分類Classificationsaccordingtoworkingprinciples沖動(dòng)式汽輪機(jī)Impulseturbines沖動(dòng)式汽輪機(jī)，蒸汽只在汽輪機(jī)的靜葉柵中降壓膨脹加速，在動(dòng)葉柵內(nèi)不降壓不膨脹，動(dòng)葉只是把蒸汽動(dòng)能轉(zhuǎn)換成機(jī)械功，同時(shí)改變汽流方向Intheimpulseturbine,pressuredrop,expansionandvelocityincreaseofsteamoccursacrossonlythestationaryblades.Pressuredropandexpansiondon’toccurinmovingblades.Themovingbladesonlyconvertsteamkineticenergyintomechanicalworkwhilechangingflowdirection.Apressuredropoccursacrossonlythestationaryblades,withanetincreaseinsteamvelocityacrossthestage.Asthesteamflowsthroughthenozzleitspressurefallsfrominletpressuretotheexitpressure(atmosphericpressure,ormoreusually,thecondenservacuum).Duetothishighratioofexpansionofsteam,thesteamleavesthenozzlewithaveryhighvelocity.Thesteamleavingthemovingbladeshasalargeportionofthemaximumvelocityofthesteamwhenleavingthenozzle.Thelossofenergyduetothishigherexitvelocityiscommonlycalledthecarryovervelocityorleavingloss.反動(dòng)式汽輪機(jī)Reactionturbines反動(dòng)式汽輪機(jī)，蒸汽在汽輪機(jī)的靜葉柵中被降壓、膨脹和加速，在動(dòng)葉柵中也被進(jìn)一步降壓、膨脹加速。動(dòng)葉不但將蒸汽的動(dòng)能，同時(shí)也將蒸汽的部分內(nèi)能轉(zhuǎn)換成機(jī)械功，這種汽輪機(jī)稱為反動(dòng)式汽輪機(jī)Inthe

reactionturbine,pressuredrop,expansionandvelocityincreaseofsteamisundergoneacrossthefixedvanesofthestatorandpressuredrop,expansionandvelocityincreaseofsteamisfurtherresultedacrossthemovingblades.Movingbladesconvertbothsteamkineticenergyandpartofitsinternalenergyintomechanicalwork.Inthe

reactionturbine,the

rotor

bladesthemselvesarearrangedtoformconvergent

nozzles.Thistypeofturbinemakesuseofthereactionforceproducedasthesteamacceleratesthroughthenozzlesformedbytherotor.Steamisdirectedontotherotorbythefixedvanesofthestator.Itleavesthestatorasajetthatfillstheentirecircumferenceoftherotor.Thesteamthenchangesdirectionandincreasesitsspeedrelativetothespeedoftheblades.Apressuredropoccursacrossboththestatorandtherotor,withsteamacceleratingthroughthestatoranddeceleratingthroughtherotor,withnonetchangeinsteamvelocityacrossthestagebutwithadecreaseinbothpressureandtemperature,reflectingtheworkperformedinthedrivingoftherotor.衡量蒸汽在動(dòng)葉柵內(nèi)膨脹過(guò)程度的參數(shù)叫反動(dòng)度。Degreeofreactionisameasurementofsteamexpansiondegreeacrossmovingblades.

反動(dòng)度定義：在葉柵中蒸汽膨脹的過(guò)程占級(jí)中總的應(yīng)該膨脹程度的比例數(shù)，或是動(dòng)?xùn)胖械睦硐腱式涤诩?jí)的總焓降之比，通常用β表示。Degreeofreactionorreactionratio(R)isdefinedastheratioofstaticpressuredropintherotortothestaticpressuredropinthestageorastheratioofstaticenthalpydropintherotortothestaticenthalpydropinthestage.Averywidelyuseddesignhashalf

degreeofreaction

or50%reactionandthisisknownasParson’sturbine.Thisconsistsofsymmetricalrotorandstatorblades.Forthisturbinethevelocitytriangleissimilarandwehave:

汽輪機(jī)的特點(diǎn)Thecharacteristicsofsteamturbine

汽輪機(jī)轉(zhuǎn)速高，高速汽輪機(jī)轉(zhuǎn)速在10000r/min以上，可直接與離心泵或離心壓縮機(jī)聯(lián)接；一般電動(dòng)機(jī)轉(zhuǎn)速只能達(dá)到工頻3000r/min(3600r/min)，與高轉(zhuǎn)速的泵或離心壓縮機(jī)聯(lián)接時(shí)，還需要設(shè)置增速設(shè)備。Rotatingspeedofsteamturbinecanbeveryhigh.Thespeedofahighspeedturbinecanbeashighasabove10000r/minandcanbedirectlycoupledtocentrifugalpumporcentrifugalcompressor;Rotatingspeedofacommonlyusedmotorcanreach3000r/minpowerfrequency(3600r/min),andaspeedincreasingequipmentisneededwhencoupledtohighspeedpumporcentrifugalcompressor.Theturbinesusedforelectricpowergenerationaremostoftendirectlycoupledtotheirgenerators.汽輪機(jī)的轉(zhuǎn)速在一定范圍內(nèi)變動(dòng)，增加了調(diào)節(jié)手段和操作的靈活性，電機(jī)的轉(zhuǎn)速是固定的，調(diào)速需要增加調(diào)速設(shè)備。（機(jī)械可用液力耦合器、電子的可使用變頻）Therotatingspeedofasteamturbinecanvarywithinarangewhichmakeitflexibleandadjustable.However,motorhasaconstantrotatingspeedanditwillneedadditionalspeedregulationequipmentforspeedchange(fluidcoupling(mechanical)orfrequencyconverter(electronic)).汽輪機(jī)驅(qū)動(dòng)適應(yīng)輸送或壓縮易燃易爆介質(zhì)，即使有泄漏也不會(huì)由原動(dòng)機(jī)引起事故，電機(jī)驅(qū)動(dòng)必須采取有效的防爆措施。Steamturbinesaresuitableforbeingusedasdriveintransportingandcompressingexplosivematerialandevenaleakagecannotresultinanaccidentfromdrivingmachine.However,amotordrivemusttakeeffectiveexplosionpreventionmeasures.汽輪機(jī)使用蒸汽驅(qū)動(dòng)，煉廠都有自備的熱電廠，蒸汽來(lái)源穩(wěn)定，而電動(dòng)機(jī)要受電網(wǎng)的影響，正由于汽輪機(jī)可直接驅(qū)動(dòng)較大型的高速煉油化工機(jī)器。而且具有啟動(dòng)扭矩大，容易實(shí)現(xiàn)轉(zhuǎn)速調(diào)節(jié)，適宜在防爆區(qū)域工作，故在煉油化工行業(yè)得到廣泛的運(yùn)用。Steamturbinesusesteamasdrivingpowerwhichcanbereceivedfromreliablesourcesofself-containedthermalpowerplantinrefinery.However,amotorhavetodependonpowergridandsusceptibletoitsinfluence.Theadvantagesofitscapablecouplingdirectlytolargehighspeedmachineforpetrochemicalplant,greatstartuptorque,easyofspeedregulation,suitableforoperationinexplosion-proofareas,thesteamturbinesarewidelyusedinpetrochemicalindustry.按排氣方式分類Classificationsaccordingtoexhaustconditions凝汽式汽輪機(jī)Condensingturbines背壓式汽輪機(jī)Backpressureturbines抽氣式汽輪機(jī)Extractingtypeturbines還有按能量傳遞方式分類、蒸汽流道數(shù)目分類、蒸汽流道類型分類。Therearealsotypesclassifiedaccordingtoenergytransfer,numberofsteamchannelsandtypesofsteamchannels.凝氣式汽輪機(jī)Condensingturbine背壓式汽輪機(jī)Backpressureturbine抽氣式汽輪機(jī)Extractingtypeturbine汽輪機(jī)Steamturbine汽輪機(jī)主要零部件的結(jié)構(gòu)與作用Structureandfunctionsofthemainpartsofsteamturbine汽輪機(jī)調(diào)速系統(tǒng)Speedregulationofsteamturbine汽輪機(jī)的輔助設(shè)備Auxiliaryequipmentofsteamturbine汽輪機(jī)開停機(jī)Startupandstopofsteamturbine汽輪機(jī)常見故障及處理

Commonfaultsandtroubleshooting汽輪機(jī)主要結(jié)構(gòu)與作用Themainstructuresandfunctions

汽輪機(jī)典型結(jié)構(gòu)Typicalstructureofsteamturbine轉(zhuǎn)子Rotor軸承Bearings調(diào)節(jié)閥Control(governing)valve氣缸Casing蒸汽室Steamchest靜葉持環(huán)Stationarybladering汽封Vapourseal汽輪機(jī)典型結(jié)構(gòu)（背壓式）Typicalstructureofsteamturbine(Backpressuretype)調(diào)節(jié)閥Regulatingvalve

轉(zhuǎn)子Rotor危機(jī)保安器Emergencygovernor前軸承支座

Frontbearinghousing汽缸Casing盤車裝置

Turninggear汽輪機(jī)典型結(jié)構(gòu)（凝汽式）Typicalstructureofsteamturbine(Condensingtype)調(diào)節(jié)閥Regulatingvalve

轉(zhuǎn)子Rotor危機(jī)保安器

Emergencygovernor前軸承支座

Frontbearinghousing汽缸Casing盤車裝置

Turninggear后軸承支座

Rearbearinghousing轉(zhuǎn)子Rotor轉(zhuǎn)子為整體鍛件，轉(zhuǎn)子上的動(dòng)葉分為調(diào)節(jié)級(jí)動(dòng)葉governingstageblade和壓力級(jí)動(dòng)葉。葉片的型線及葉根結(jié)構(gòu)是不同的，各級(jí)葉片均為不調(diào)頻，以適應(yīng)機(jī)組大范圍變速運(yùn)行的要求。Therotorissolidforged.Themovingbladesonrotorincludegoverningstagebladesandpressuringstageblades.Thebladeprofilesandbladerootstructuresaredifferent.Allthebladesofeverystageareuntunedbladestomeetwide-rangespeedregulatingrequirement.危急保安器的作用是在汽輪機(jī)轉(zhuǎn)速超過(guò)規(guī)定值時(shí)產(chǎn)生作用，起到停機(jī)保護(hù)作用。它是與危急遮斷油門配對(duì)的。Theemergencygovernorwillactwhensteamturbinespeedexceedtherequiredvaluetostopandprotectthemachine.Itactsthroughemergencygovernorpilotvalve.推力盤承受汽輪機(jī)運(yùn)行產(chǎn)生的軸向力，也是轉(zhuǎn)子與靜止部件的定位部件。Thrustcollar

bearthethrustforceresultedwhensteamturbinerunning.Itisalsoapositioningpartbetweenrotorandstationaryparts.凝汽式汽輪機(jī)轉(zhuǎn)子Steamturbinerotor(Condensingtype)背壓式汽輪機(jī)轉(zhuǎn)子Steamturbinerotor(Backpressuretype)前軸承支座Frontbearinghousing用以支持汽缸及轉(zhuǎn)子，并可準(zhǔn)確地保持相互間的位置，另外汽缸和前軸承座通過(guò)兩拉桿螺釘?shù)倪B接，使汽缸和軸承座在調(diào)整好的正確位置上固定下來(lái)。Forcasingandrotorsupportingandtokeepaccuraterelativepositionsbetweenthem.CasingandFrontbearinghousingareconnectedbytworodscrewstoadjusttherelativepositionsandfixthem.推力軸承Thrustbearing推力盤Thrustcollar油封Oilseal徑向軸承Radialbearing測(cè)速訊號(hào)盤Signalpanelforspeeddetection后軸承支座Rearbearinghousing后支座是支承汽缸和轉(zhuǎn)子，并用于這些部件相互位置的調(diào)整。

Itisusedforcasingandrotorsupportingandtoadjusttherelativepositionsbetweenthem.油封Oilseal徑向瓦Radialpad盤車棘輪Barringratchet徑向軸承Radialbearing

作用：Functions:汽輪機(jī)轉(zhuǎn)子通過(guò)徑向軸承支持在軸承座上，故軸承的作用是承受著轉(zhuǎn)子在啟動(dòng)增速，穩(wěn)定運(yùn)行及停在降速時(shí)所產(chǎn)生的全部靜負(fù)荷和動(dòng)負(fù)荷（包括可能出現(xiàn)的振動(dòng)）。同時(shí)還要保持轉(zhuǎn)子中心與汽輪機(jī)汽缸、汽封、導(dǎo)葉持環(huán)等設(shè)計(jì)的間隙。Steamturbinerotorissupportedonbearinghousingthroughradialbearing,therefore,thefunctionsofthebearingsistobearallthestaticloadanddynamicloads(andanyvibrationpossiblyoccurred)

atthetimeofstartup,normaloperationandspeeddown.Italsokeepsthedesignclearancesbetweenrotorandcasing,vaporsealandguidebladering.結(jié)構(gòu)：Structure:徑向軸承由上下兩半軸瓦組成，軸瓦由錐形銷釘來(lái)固定，并通過(guò)螺栓把上下兩半連接起來(lái)。軸承的承載面澆有巴氏合金。下半軸瓦與下半軸承箱中分面用圓柱銷釘定位，以阻止軸瓦徑向或軸向移動(dòng)。Radialbearingcomprisesupperhalfandlowerhalfbearingbushwhichisfixedbytapereddowelandconnectedbybolts.TheloadingsurfacesofthebearingispouredwithBabbitt.Thelowerhalfbushisfixedonthebearinghousingsplitsurfacewith

cylindricalpintostopitsradialoraxelmovement.瓦塊軸承體油封防轉(zhuǎn)銷推力軸承Thrustbearing作用：Functions:用來(lái)承受未被平衡的轉(zhuǎn)子軸向推力，并傳遞給軸承座、推力大小主要決定于汽輪機(jī)運(yùn)行工況，另外推力軸承限定了轉(zhuǎn)子與汽缸的軸向相對(duì)位置。Tobeartheaxelunbalancedthrustfromrotorandtransmittheforcetobearinghouse.Thrustmagnitudemainlydependsonthesteamturbineoperationcondition.Thrustbearingalsofixtherelativepositionbetweenrotorandcasing.結(jié)構(gòu)：Structure:推力軸承安裝在前軸承座中，其由推力軸承體及傾斜式推力瓦塊組成。推力瓦塊上澆有巴氏合金，瓦塊分布在推力盤兩邊的圓周上，可繞徑向棱邊適量迥轉(zhuǎn)，因此推力盤與推力瓦塊表面形成理想潤(rùn)滑油楔。推力瓦塊用徑向園柱銷釘限位，防止周向移位，軸承體外部有兩凸肩，并配有調(diào)整墊片，用以調(diào)整軸承體（或轉(zhuǎn)子）與軸承座的相對(duì)位置。Thrustbearingisinstalledinthefrontbearinghousingandcomprisesbearingbodyandtiltingpadswithbabbittpouredonit.Thepadsarearrangedinacirclearoundtheshaft,andwhicharefreetopivot.Thesecreatewedge-shapedregionsofoilinsidethebearingbetweenthepadsandarotatingdisk,whichsupporttheappliedthrustandeliminatemetal-on-metalcontact.Thethrustpadsarefixedwithcylindricalpintostopcirclemovement.Therearetwoshouldersontheoutsideofthebearingbodywhichareequippedwithadjustingshimfortherelativepositionadjustingbetweenbearingbody(orrotor)andbearinghousing.軸承體Bearingbody瓦塊Pad熱電偶Thermalcouple調(diào)節(jié)閥Regulatingsteamvalve

調(diào)節(jié)閥是由調(diào)速系統(tǒng)控制液壓油缸帶動(dòng)杠桿上下移動(dòng)，油缸向下移動(dòng)，拉桿帶動(dòng)閥梁上移，在閥梁上的閥碟也隨之上移，調(diào)節(jié)氣門的間隙增大，進(jìn)入的蒸汽也隨之增大，汽輪機(jī)的輸出功率增大。注：閥碟在閥梁上的活動(dòng)的寸是不同的，也不是按順序排列的。Thegovernorisoperatedbyspeedgoverningsystemtocontrolhydrauliccylinderwhichmovetheleverupanddown.Downwardmovementofhydrauliccylinderwillpullthevalverodmoveupwhichliftsvalvesettingtogetherwithvalvebeam.Thisincreasesthegapoftheregulatingvalveresultinglargeramountofcomingsteamwithlargersteamturbinepoweroutput.Note:Themovementrangeofthevalvesettingsaredifferentandtheyarenotarrangedregularly.閥梁Valvestem閥碟Valvedisc拉桿孔Theholeforrod1Lever2Connectingplate3Valvecover4Cylindersteamchamber5Valvestem6Valvedisc7Bush8Valveseat9Valvepole10Lowerguidesleeve11Bracket12Upperguidesleeve13Support14Springcomponents15Oilmotivator汽缸Cylinder汽缸包括：Comprises:外缸Outercylinder內(nèi)缸Innercylinder前氣封Frontgasseal后氣封Reargasseal蒸汽室Steamchest高壓導(dǎo)葉持環(huán)Highpressureguidebladeretainingring低壓導(dǎo)葉持環(huán)