仪表防爆及接地系统施工方案中英

仪表防爆及接地系统施工方案 Construction SchemeforInstrumentExplosionproofandEarthingSystem编制说明：1在现代工业生产装置中，许多易燃、易爆、易挥发的工艺介质出现在生产流程中，防爆施工对装置的安全运行非常重要；各种工艺参数的检测、显示和控制都实现了自动化、集中化、智能化，特别是集散控制系统（ DCS）的广泛应用，对仪表接地系统的要求越来越高。正确完成仪表接地系统，对保证设备及人身安全，保证装置安全运行意义重大。为了高速优质地完成装置防爆及接地施工任务，特编制本方案。编制依据22.1设计施工图及其它设计文件。2.2现行《自动化仪表工程施工及验收规范》。2.3现行的《电气装置安装工程施工及验收规范》。2.4现行《自动化仪表工程质量检验评定标准》。2.5厂商提供的产品安装使用说明书等技术文件。2.6公司《质量保证手册》、《质量体系子程序》及其支撑性文件。工程概况3.工程概况应包括：工程名称、地点、规模、特点、范围、主要技术参数、主要实物工程量、工期要求及投资等。4.防爆施工：Explosion-proofConstruction:4.1一般规定：GeneralRegulations:爆炸和火灾危险区域使用的电气、

仪表设备的防爆形式及配线方式必须符

合设计要求，并满足使用区域的防爆等级规定。

Thestyleofexplosion-proofandwiringforelectricequipmentandinstrumentequipment,whichusedinexplosionandfiredangerousareas,mustaccordwiththedesignrequirementandcontentwithexplosionproofclassstipulation.安装在爆炸和火灾危险区域的仪表、电气设备和材料，必须具有符合现行国家或行业标准中规定的防爆质量技术鉴定文件和防爆产品出厂合格证．书。设备、材料的外观应无损伤和裂纹。Concerningelectricandinstrumentalequipmentandmaterialthatisinstalledinexplosionandfiredangerousarea,theirexplosion-proofqualitytechniqueappraisaldocumentandexplosion-proofmanufacturecertificatemustbecompliancewiththenewstandardrequirementofcountryorvocation.Therearen'tdamageandcrackinappearanceofdeviceandmaterial.在爆炸和火灾危险场所使用的防爆电气、仪表设备，应有铭牌和防爆标志，并在铭牌上标明国家授权的部门所发给的防爆合格证编号。Fortheexplosion-proofelectricandinstrumentalequipmentthatisusedinexplosionandfiredangerousarea,thenameplateandexplosion-proofmarkshouldappearontheequipment,thenumberofexplosion-proofcertificateissuedbythedepartmentofnationalaccreditationshouldbeprovidedonnameplate.在爆炸和火灾危险场所安装的正压通风的仪表盘（箱） 、接线箱及电气、仪表设备、除本质安全型外，应有“电源未切断不得打开”的标志。Thepluspressureventilationinstrumentpanel(box),junctionbox,electricequipmentandinstrumentequipmentinstalledinexplosiveandfiredangerousarea,excepttheintrinsicallysafetype,itshouldhas“Donotopenwhenenergized”notice.仪表电气线路采用的电缆沟、汇线槽、保护管和仪表连接管路在穿越不同防爆等级的爆炸和火灾区域的分隔间壁时，在分隔间壁外，必须做充填密封。Fortrench,cabletray,protectionpipeusedforinstrumentelectriccircuitandinstrumentconnectionpiping,iftheycrosstheseparatedroomindifferentexplosion-proofclassexplosionandfirearea,fillingandsealingshouldbedoneoutsidetheseparatedroom.4.2设备安装ErectingEquipment:采用正压通风防爆的仪表盘（箱），接线箱，安装后应保证箱内压力维持在不低于设计规定的压力值，当有低压力时,其联锁或报井装置动作应准确、可靠。Fortheexplosion-proofinstrumentpanel(box),junctionboxwithpluspressureventilation,aftertheyareinstalled,thepressureinboxandinterlockthepressure.designthethanlowernoensuredbeshouldalarmunitshouldactcorrectlyandreliablywhenthepressureislow.采用正压通风防爆的仪表盘（箱）、接线箱，其正压力通风管路必须保持畅通，且不宜安装切断阀。Theexplosion-proofinstrumentpanel(box),junctionboxadoptingpluspressureairiness,itspluspressureairinesspipingmustremainaccessibleandshouldnotmountshuttingoffvalue.在爆炸和火灾危险场所安装的仪表箱、 分线箱、接线盒及防爆仪表、 电气设备引入电缆时，应采用防爆密封填料进行密封； 多根电缆穿一根管时， 可用密封盒并用适当填充料密封。 外壳上多余的孔应做防爆密封。Fortheinstrumentbox,junctionbox,wiringbox，explosion-proofinstrumentandelectricequipmentwhichinstalledinexplosionandfiredangerousareas,theentranceofcableshouldbesealedwithexplosion-proofsealfilling.Whenoneconduitcontainsmultiplecable,theentrancecanmountsealingboxwithproprietyfilling.Doexplosion-proofsealingtospareholesinshell.防爆仪表箱、分线箱、接线箱的门（盖）应有弹性密封垫圈， 或隔防密封面连接螺栓应均Theseparatedboardsshould匀紧密，并应有弹簧垫。Coversshouldhavespringsealingwasherforexplosion-proofinstrumentbox,junctionbox,andconnectionbox.Andconnectionboltsandnutsofshallbetightequablyandhavefaceandseparatingpreventingspringwasher.防爆电气、仪表设备的安装应牢固，内部接线必须正确、牢固，并有防松和防拔脱装置。Theexplosion-proofelectricandinstrumentdevicesshallbeinstalledfirmly.Insidewiringmustbecorrectandfirmwithlooseness-proofandshedding-proofunit.电气线路安装ErectingElectricalcableline:穿越不同等级的爆炸和火灾危险区域分隔间壁的电缆沟的密封措施：Sealingwayfortrenchthatcrossesseparatedwallsbelongingtodifferentclassofexplosionandfiredangerousareas:a.电缆沟内充砂密封，可敷设一层电缆，充填一层砂，砂层厚约 100mm。 电缆全部敷设完后，充砂填满电缆沟。Methodoffillingfinesandintotrench:fillingone-layersandabout100mmdepthafterinstallonelayercable.Thetrenchshallbefullofsandafterallcablelayout.。1mb.在分界处两侧安装隔板，隔板之间充砂，长度不少于befixedatbothsidesofinterface,zonebetweenboardsshallbefilledwithsand,andthelengthisnolessthan1m.c.在分界处用阻火密封填料充填。Sealingwithfire-resistantfillingattheinterfaces.取的密汇线槽穿越不同级别的爆炸，火灾危险区域分界处时，可采 封措施：Takingairproofmeasureswherecabletraypassesthroughtheinterfaceofdifferentclassexplosionandfiredangerousareas:在分界处作气密砂封。 a.Carryoutsealwithsandattheinterface.b.在分界处用阻火密封填料充填，形成密封阻挡层。Sealwithfire-resistantsealfillingattheinterfaceandformsealingandresistantlayer.敷设在爆炸和火灾危险区域内的电缆（线）保护管应选用厚壁镀锌管。选用的管件应按危险区域的级别采用合适的防爆结构形式。Choosethick-wallgalvanizedconduitascableprotectiveconduitlaidinexplosionandfiredangerousareas.Selectedpipepiecesshouldadoptproperexplosion-proofstructureandtypeaccordingtorequirementsofthedangerousareasclass.保护管与设备或管件之间的连接应采用圆柱管螺纹连接，螺纹有效啮合部分应在 6螺距以上，与设备连接应用锁紧螺母锁紧。 螺纹上应涂电力复合脂或导电性防锈脂。 不得在螺纹上 缠麻涂铅油、缠绝缘胶带或涂其它油漆。Adoptcylindricalgasthreadtoconnectconduitanddevicesorpipe-pieces.Makesurethateffectiveengagementismorethansixpitchesandlocktightlyequipmentswithlocknut.Thethreadshallbepaintedwithelectricpoly-greaseorconductiveantirustgrease.Notwringhempropes,notwringinsulatedtapeandnotpaintleadoilorotherpainting.仪表电气线路，在防爆区内不应有中间接头，当必须有中间接头时，应在防爆接线箱内进行，且应连接牢固、紧密，接头良好并有防松和防拔脱装置。Instrumentelectricalcircuitshallnothavemiddlejointinexplosion-proofarea.Ifitisobligatory,jointshallbeintheexplosionelectricalrightallhavetight,andhardconnectionkeepbox,junctionconductivitywithlooseness-proofandshedding-proofunit.线路沿工艺管架敷设时，其位置应在爆炸和火灾危险性小的一侧Whenlaylinealongtheprocesspipestanchion,layoutlocationshouldbeatthesidethatpossibilityofexplosionandfireislittle.当工艺管线内爆炸和火灾危险介质的密度大于空气时，应在工艺管道的上 方，反之，应在其下方。Whendensityofexplosionandfiredangerousmediumintheprocesspipeisheavierthanthatofair,itslayoutlocationshouldbeabovetheprocesspipe;onthecontrary,itslayoutlocationshallbebelow.保护管与现场仪表设备连接时，应安装隔爆密封管件并做充填密封，密封管件与仪表设备之间的距离不应大于0.45m。密封管件与仪表之间的连接可采用挠性连接管，并按防爆要求书进行装配。挠性连接管的材质应与使用环境条件相符适合。Whenconnectprotectionpipewithinstrumentequipmentatsite,theexplosion-proofandairtightpipeconnectorsshallbeinstalled,filledandsealed.Makesurethatthedistancebetweenairproofpipeconnectorsandinstrumentequipmentisnomorethan0.45m.Theflexiblepipecanbeusedtoconnectairtightpiecesandinstrumentandmountaccordingtoexplosion-proofinstructionbook.Atmeantime,flexiblematerialshallagreewithapplicationcondition.4.4本安系统施工：ConstructionofIntrinsicallySafeSystem:本质安全线路及其附件，应具有耐久性兰色标记。Theintrinsicallysafelineandaccessoriesshallbemarkedwithbluewearmark.本质安全线路与非本质安全线路之间应加屏蔽，且保持一定的距离。 separatetheintrinsicallysafecircuitfromthenon -intrinsicallysafecircuitandkeepsomedistancebetweenthem.本质安全线路中的安全栅、隔离器等关联设备的安装位置，应在安全场所一侧，或置于另一与环境相适应的防爆设备外壳内。需接地的关联设备， 应可靠接地。Safebars,separatorsandotherrelatedequipmentsintheintrinsicallysafelineshallbeerectedatthesideofsafelocationorintoexplosion-proofdeviceshellthataccordswithconditions.Equipmentsneededearthingshallbereliablygrounded.不同系列的本质安全型仪表及本质安全线路的关联设备，必须有国家授权的部门发给的产品生产许可证和防爆合格证，其型号规格的替代，必须经原设计单位以文件形式确认。Forrelateddevicesofvariousseriesintrinsicallysafeinstrumentsandlines,theirmanufacture'slicenseandexplosionproofcertificate,approvedbynationalauthoritydepartment,mustbeprovided.Ifwanttoreplacethem,theirspecificationsandtypesmustbeapprovedbyprimarydesignunitinformoffiles.5.接地系统施工：ConstructionforEarthingSystem:5.1一般规定：GeneralRegulations:仪表接地系统一般分为保护接地、信号回路接地、屏蔽接地和本安系 统接地四种。Instrumentearthingsystemgenerallycomprisesoffourtypes:safeguardearthing,signalloopearthing,shieldearthingandintrinsicallysafeearthing仪表系统的各种接地应各成系统，互相分开，各自接地母线，接地干 线，分支线之间应彼此绝缘。Allearthlingsofinstrumentsystemshouldhaveitsownsystem,everyearthlingsystemshallseparateandconnecttoitsownearthingbus.Busandbranch-lineshouldbeinsulatedeachother.仪表接地系统的接地电阻值，应分别符合各自系统的厂商技术文件或 设计文件的要求。 Earthingresistanceofinstrumentearthingsystemshouldbecompliancewithrequirementsofmanufacture'stechnicalfilesordesignfilesforrespective当有防干扰需求时，多芯电缆中的备用芯线应在一点接地。屏蔽电缆的备用芯线与电缆屏蔽层，应在同一侧接地。 Whenitisneededtopreventdisturbance,sparecoresofmulti-corecableshouldbegroundedatonepoint.Sparecoresofshieldedcableanditsshieldshouldbegroundedatthesameside.接地线的颜色应符合设计规定，并设置黄 /绿标志。Colorofearthingwireshouldconformtodesignregulationsandsetyellow-greensign.接地系统的连线应使用铜芯绝缘电缆或电线，采用铜质螺栓紧固。仪表盘（箱） 、柜内的接地汇流排，应使用铜材，并由绝缘支架固定。接地总干线 与接地体之间应采用焊接。Connectionlineforearthingsystemshouldapplywithcopper-coreinsulatedcableorwireandfastenoncopperboltandnut.Earthingbusbarinsideinstrumentpanel(box)orcabinetshallbemadeofcopperandbefixedbyinsulatedsupport.Applyweldingbetweenearthingmainlineandearthingpole.自己制作接地汇流排时， 连接螺栓与汇流排之间的连接宜采用在汇流排上攻丝的方式连接。Whenfabricateearthingbusbarbyourselves,connectboltwithbusbarbytappingthread.5.2保护接地SafeguardEarthing:用电仪表的外壳，仪表盘、柜、箱、盒和电缆槽，保护管、支架底座等正常不带电的金属部分，由于绝缘破坏而有可能带危险电压者，均应做保护接地。供电电压低于或等于 24V的就地仪表、开关等，设计无特殊要求时，可不做保护接地。Allnotelectriferousmetallicpartsinnormalcondition,suchasshellofusage-powerinstruments,instrumentpanel,cabinet,box,caseandcabletray,conduit,supportfoundationetc.,shouldbeperformedsafeguardearthingiftheirinsulationlayershavebeendamagedandmayhavedangerousvoltage.Whendesigndoesnotrequire,safeguardearthingforlocalinstrument,switch,etc.,whosesupply 在非爆炸危险场所的金属盘、板上安装的按钮、信号灯、继电器等小型低压电器的金属外壳， 当与已接地的金属盘、板接触良好时， 可不做保护接地。Alllowvoltageelectricaldevicesinsmallsize,suchaspushbutton,signallight,relayetc.,fixedonmetalpanelandboardinnon-explosionarea,iftheirconnectionwithgroundedmetallicpanelorboardisingoodcondition,theirsafeguardearthingcanbeignored.保护接地系统可接到电气工程低压电气设备的保护接地网上，连接应 牢固可靠，不应串联接地。Safeguardearthingsystemcanconnecttosafeguardearthingnetforelectricengineeringlowvoltageplantsandensureconnectionreliableandhard.However,forbidexecutingserialearthing.在建筑物上安装的汇线槽及电缆保护管，当设计文件无只能一点接地的规定时，可多点接地。Forcableductandprotectivepipeerectedontobuilding,ifdesignfilesdonotrequireonlyone-pointearthing,multi-pointearthingisavailable.5.3信号回路接地：SignalLoopEarthing:信号回路的接地点应在显示仪表侧， 当采用接地型热电偶和检测元件 已接地的仪表时，不应再在显示仪表侧接地。Signalloopearthingshouldbeperformedatthesideofdisplayinstrument.Ifusingwell-groundedthermocoupleormeasuringelementsofinstrumenthavebeenearthed,earthingatthesideofdisplayisunnecessary.各仪表回路和系统只应有一个信号回路接地点除非使用隔离器将两个 接地点之间的直、流信号回路隔离开。Everyinstrumentsignalloopandsystemshouldhaveonlyone-pointearthingingeneral,exceptthatusingseparatortosegregateDCsignalloopbetweentwoearthingpoints.电磁流量计、涡轮流量计、分析仪表等仪表设备、应按仪表安装使用 说明书等厂商技术文件的要求接地Forinstrumentssuchassolenoidflowmeter,turbineflowmeterandanalyzingelements,carryoutearthingaccordingtoinstallationoroperationinstructionandmanufacture'stechniquefiles.信号回路接地可与屏蔽接地共用一个单独的接在系统。Signalloopearthingandshieldearthingcanshareasingleearthingsystem.屏蔽接地：4．ShieldEarthing:屏蔽电缆（线）屏蔽层的接地应在显示仪表侧，同一线路的屏蔽层应具有可靠的电气连续性，且只能一点接地。Performshieldearthingforshieldedcableatsideofdisplayinstrument.Forthesameconduit,ensureshieldhasreliableelectriccontinuityandearthatone-point.电缆屏蔽层在仪表盘和接线箱接线时，其屏蔽层应用绝缘保护套保护，不得与盘体或箱体接触。Whenperformingconnectioninsideofinstrumentpanelorjunctionbox,shieldshouldbeprotectedwithinsulatedsheathtopreventittouchpanelorbox.屏蔽电缆电缆头制作时，若不需将屏蔽引出，应将屏蔽层与电缆护套切断，若需要将屏蔽引出，网状屏蔽应套绝缘管，绝缘管端包在电缆头内，纸 状屏蔽应焊接引线。 Whilemakingcableterminal,ifitisunnecessarytofetchouttheshield,cutoffshieldlayerfromcablesheath.Ifnecessarytofetchoutshield,fornet-shapedshield,housinginsulatedtubeandwrappingitsendintocableterminal;forpapyraceousshield,weldingwireisrequired.。屏蔽接地的引出线截面积应不小于

Wirecross-sectionareaforshieldearthingshallbenolessthan2.1.5mm当多根屏蔽电缆固定在一起且均需要接地时，向汇流排引线应均匀分布在汇流排所有的连接点上。Whenmanyshieldedcablesarebandedtogetherandallneedearthing,connectthemequallytojointpositionofbusbar.5.5本安系统接地：EarthingforIntrinsicallySafeSystem:本质安全线路本身不接地， 但仪表功能要求接地时， 应按仪表安 装使用说明书和设计要求接地。Intrinsicallysafecircuititselfdoesnotground.Ifinstrumentfunctionrequiresittoground,carryoutearthingaccordingtoerectionandoperationinstructionanddesig