Understanding Well Construction and Surface Footprint
Transcript of Understanding Well Construction and Surface Footprint
Understanding Well Construction and
Surface Footprint
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Well Site Planning & Preparation Drilling Casing & Cement Completion & Stimulation Site Maintenance
Well Construction Timeline
Stage 1: Planning and Preparation• AcquireSurfaceLease
Agreement• Determinationofmulti-wellpad
orsinglewellpadrequirements• Informstakeholdersofthe
proposedwellconstruction• Evaluationofsourgas
probability;thiswillinfluenceequipmentlocation,etc.
• AcquireWelllicense(s)• ObtainOperation(s)permits• SiteExcavationandPreparation• Thepreparationofthelocation
wouldincludethedrillingofinitial“rathole/mousehole”andplacementofconductorstring/pipe
• Identifysafetyprocedures,environmentalandregulatoryrequirements
• Outlinetheemergencyresponseplans/procedures
Stage 2: Drilling• Drillingrigandequipment
mobilization(ifnotusedforSurfaceHoledrilling)
• Drillingfluids/mud–testingandrecycling
• BlowOutPreventer(BOP)installation
• Surface,andintermediate(insomecases)casingcementedintothewellbore
• Drillcuttingsamplestakenandanalyzed(ongoingthroughoutthedrillingprocess)
• Wellboredrilledtototaldepth(vertical,directionalorhorizontal)
• Potentialreservoir(s)identifiedandevaluatedusinggeophysicalloggingtechniques
Most stages of well construction include stakeholder dialogue. Consultation with stakeholders is the responsibility of the individual project proponent.
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Well Site Planning & Preparation Drilling Casing & Cement Completion & Stimulation Site Maintenance
Well Construction Tim
eline
Stage 3: Casing and Cement• Productioncasing
loweredintothewellandcementedintoplace
• Diagnostictoolsareutilizedtoensurewellboreintegrity
Stage 4: Completion & Stimulation• Drillingrigismovedoffsiteand
permanentwellheadinstalled• Stimulationequipmentismoved
intoplace• Reservoirhorizonsare
perforatedandthenstimulated• Stimulationequipmentismoved
offsite• Producingzonesaretested• Withthedrillingandcompletion
equipmentdemobilized,thesurfacefootprintisdramaticallyreduced.
Aftercasing,cementingandwellstimulationactivitiesarecompleted,andassumingthewellissuccessful,therewillbeadditionalconstructionactivityonsitetoinstallsurfacefacilitiesifrequired,tiethewellintothepipelineinfrastructure,andcontourandreclaimpartoftheleasesite.
Thisinformationbookletdiscusseswellconstructionpracticesonly.Formoreinformationaboutthecompletionsprocess,includingHydraulicFracturingorotherstimulationtechniques,pleasereferenceUnderstanding Hydraulic FracturingorUnderstanding Water and Unconventional Resourcesatwww.csur.com
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Well Site Planning & Preparation
Single vs. Multi-well padAstandardsinglewellleasesiteforconventionaloilorgaswilltypicallyaffectasurfaceareameasuring100metresby100metres.Theleasesitewilltypicallyholdthedrillingrigandadditionalequipmentalongwithsupervisoryaccommodationandmaterialstorage.Ifmultiplewellsfromasinglepadareplanned,thesurfaceareaoftheleasesitewouldbelarger;insomecasesasmuchasdoublethesize.(100metresby200metres.)Whileamulti-wellpadsitewillhavealargersurfacearea,thecumulativesurfaceimpactofthetotalnumberofwellsdrilledintheprojectareawillbesmaller.Padsitesallowmultiplewellstobedrilledfromonesurfacelease,therebyreducingthetotalsurfacearearequiredforoilandgasdevelopment.Oncedrillingiscompletedandthewell(s)is/areconnected/tied-intothepipeline,aportionoftheleaseareacanbereclaimedtominimizesurfacedisturbance.
Surface Lease Site AgreementAsurfaceleasesiteagreementgrantsacompanyaccesstodrillawell(s)onlandthatisheldeitherprivately,bythecrownorbyaFirstNation.Theagreementalsospecifiesanyconditionsrelatingtothecommitmentsandresponsibilitiesofboththecompanyandthelandowner,includingthepaymentofcompensationbythecompanytothelandowner.
License & PermitFederaland/orProvincialandMunicipallicensesandpermitsarerequiredforleasesiteconstruction;projectspecificrequirementswillvarydependingonthelocationofthewell.
Excavation & LevelingToprepareforinitialdrilling,theleasesiteisleveled,ifnecessary,withabulldozerand/orgrader,withcarefulconsiderationgiventoburiedpipelinesandutilities,aswellasproximitytosurfacewaterfeatures.Thescaleanddurationofleasesitepreparationissite-specific.Onsomedrillingsites,acellarmaybeexcavated.Thisiswherethemainboreholeistobedrilled.Areservepitandsettlingpitsmaybeexcavatedandareusedforwaterordrilling fluid(mud)discharges.Oftenthesoillayersareseparatedforbettersoilconservation.Uponcompletionofthedrilling,thesoilscanthenberestoredtotheiroriginallocation.
Excavated lease site
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Well Site Planning &
Preparation
Drilling of the “Surface Hole” , etc. Aspartofanyoilorgaswell,aconductorholeandsurfaceholearerequiredaspartoftheentirewellbore.Commonly,aratholeand/oramouseholearedrilledpriortotheactualdrillingofthewelltoreservoirdepth.Aconductorhole,alsoreferredtoasa“starterhole”isalargediameterhole,linedwithpipewhichvariesindepth,andisusedtohousetheBOP(BlowOutPreventer).Aratholeisaholelyingbelowtherigfloor,30to35feetdeep,linedwithcasingintowhichthekellyisplacedwhenhoistingoperationsareinprogress.Amouseholeisashallowboreholeundertherigfloor,usuallylinedwithpipe,intowhichjointsofdrillpipearetemporarilyplacedduringdrillingoperations.Theseareeitherdonebytheportablerigthatdrillstheconductorhole,orcanbedonebytheprimaryrigafterrigging-up.Thesurfaceholeisdrilledandcasedtoisolatepotentialshallowgroundwateraquifersfromthewellbore.
Safety Procedures & Emergency Response PlansAlldrillingsitesaretypicallyclassifiedaccordingtoareasofpotentialand/oractualexposuretoHydrogen Sulfide (H2S).H2Sisanextremelytoxicandpoisonousgas.Employerswilltakespecialprecautionswhenchoosingequipment.WellsiteemployeesaretrainedtorespondaccordinglyshouldtheyencounterH2S.Underthesecircumstances,allemployeesarerequiredtowearspecially
approvedmasksandairsupplyequipment.Therecommendationsandemployeeinstructionwillvarydependingonthetypeofarea,aswilltheemergencyresponseplans(ERPs)thatareinplace
Environmental and Regulatory ConsiderationsProvincialandfederalregulations,whichgoverntheoilandgasindustry,havebeeninplaceformanyyears.Theyhavebeenestablishedtoensurethatboththepublicandtheenvironmentareprotectedthroughoutexploration,developmentandproductionofhydrocarbonresources.Regulationsarealsocontinuallyreviewedandrevised,asrequired,inresponsetoadvancementsinindustrytechnologiesandthetechniquesemployedtoextracttheresource.
Thefundamentalregulatorybasicsofsurfaceandgroundwaterprotection,wellboreintegrity,leaseconstruction,forexample,applytoalltypesofhydrocarbondevelopments;includingunconventionalresources.Similarly,theuseofwaterfordrillingandcompletionactivitiesrequireapprovalsorpermitsfromappropriateauthorities.
Prior to acquisition of the surface lease site, a number of different steps are required. Requirements will vary depending on the location of the proposed development and jurisdictional prerequisites.
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Drilling
Equipment Assembly and PlacementAsite,anditsaccessroad,mustaccommodatealargenumberoftemporaryandsemi-permanentstructuresandtanks,allbroughtinbytruck.Atanewly-prepareddrillsite,thestabilityofthewellpadisnecessarytosupportthedrillingrigandauxiliaryequipmentrequiredonsite.Insomelocalitieswherethegroundisunstablerigmatsarecommonlyused.Afterthewellpadisproperlypreparedthedrillingrigisthenunloadedandassembled.
Therearemanyrigdesigns,andthisbookletdoesnotcovereachtypeindividually.Duringassemblyoftherig,someequipmentmaybehandledandsetwithcrane,riguptrucks,orforklift,dependingonthesizeoftherig.
Thesubstructureisassembled,pinnedtogether,leveled,andtiedintootherrigcomponents.Oncethesubstructureissetinplace,installingthepowersystemandraisingthederrickbegins.Mostdrillingrigsarepoweredbyelectricitythatisdeliveredbyonsitedieselpoweredgenerators.
Whileonecrewfinishespreparingtherigfloor,anothercrewmightberiggingupthecirculatingsystem.Themudtanksandmudpumpsaresetintothepredeterminedlocation.
Oncealladditionaldrillingandauxiliaryequipmentaresetintoplaceafinalinspectioncanbedone.Theentireprocessofrigging-upcantakeoneortwodays.Wheremultiplewellsaredrilledfromasinglepad,commonlythedrillingrigwillhavetheabilitytomovetothenextlocationontheleasewithminimaldisassembly/reassembly.
Drilling boreholes deep into the ground and preparing them to produce oil and gas is a highly technical and specialized process. Throughout the operation, custom-designed fluids fulfill many different roles. While drilling, these include: lubricating the drill bit; circulating drilled-up rock out of the hole; containing formation fluids within the hole; and facilitating operation of sophisticated formation evaluation tools. Fluids may be water-based, oil-based, or synthetic.
Source: Shale Exploration
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Drilling
Core SamplesInsomecases,acoresampleoftheformationistakenfortesting.Aspecialcorebarrelisloweredtothebottomonthedrill stringandisrotatedtocutacorefromtheformation.Thiscoreisbroughttothesurfaceandexaminedinalaboratory.Somecoreorchipanalysismayoccuratthetemporaryon-sitelabwhileothercoresamplesaresealedandshippedtospecializedlabsforin-depthreservoircharacteristicandcoreanalysis.
Vertical vs. HorizontalAlthoughhistoricallyoilandgaswellshavebeendrilledvertically,newtechnologieshavemadeitpossibleforwellstobedrilledhorizontally.Thepurposeofdrillingahorizontalwellistoincreaseamountofreservoirrockthatisintersectedfromthewellbore.Horizontaldrillingfirstentailsdrillingaverticalwelltoapredetermineddepthabovethereservoir.Thewellisthendrilledatanincreasingangleuntilitintersectsthereservoirintervalinahorizontalplane.Oncehorizontal,thewellisthendrilledtoaselectedlength,whichcouldextendtoasmuchas3500m.Thisportionofthewell,calledthehorizontalleg,allowssignificantlyincreasedcontactofthewellborewiththereservoircomparedtoaverticalwell.Uponcompletionofdrilling,production casingiscommonlyplacedintothewellbore.Aperforating
gunisloweredintothewellboreandplacedinaselectedintervalwithinthehorizontalleg.Itisthenactivatedtocreateaseriesofholesinthecasingtoallowcommunicationbetweenthereservoirandthewellbore
Source: Kocurek Industries
Example of a core sample. Typically 12
inches in length and 8 inches in
diameter. The pitted surface
represents visible pore space.
Step 1Drillverticallyuntilthewellbore
reachesapointabovethetargetedreservoir.
Step 2“Kickoff”andbegintodrillatan
increasingangleuntilthewellborerunshorizontallythroughthe
targetedreservoir.
Step 3Drillhorizontallytodesiredlength.
Source: Kocurek Industries
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Casing and Cement
Wellconstructionactivitiesareengineeredtoensurethatgroundwaterbearinghorizonsareisolatedfromthewellbore.Thisprocesseliminatesthepotentialforcommunicationsandpossiblecontaminationduringsubsequentdrilling,completionandfinalproductionoperations.Toprovidetheprotectionnecessary,usuallyanumberofstepsarecompletedtoisolatethewellborefromthesurroundingrockintervalsthathavebeenpenetratedduringthedrillingprocess.
Step 1 Oncetheconductorpipehasbeenputinplacethesurfaceholeisdrilledtothebaseofgroundwaterprotection,asdefinedbytheregulatorybody.Surfacecasingisloweredintotheholeandcementedinplace.Atthisstage,abarrierofsteelANDcementiscreatedtopreventthecontaminationofpotentialshallowgroundwateraquifersaswellprovidewellborestabilityfortheremainingdrillhole.
Step 2 Thecementisallowedtosetpriortocontinuationofdrillingandinsomejurisdictions,a“cementbond”geophysical logisruntodeterminetheintegrityofthecementthatsurroundsthesurfacecasing.
Step 3 Thewellboreisthendrilledtoitstotaldepth.Insomecases,dependingonthetotaldepthofthewellortheorientation(horizontalor
vertical)anintermediatesetofcasingmaybeinsertedintothewellboreandcementedinplace.Theprocessofinstallationandcementingofintermediateandproductioncasingissimilartosurfacecasing.Thedecisiontoinstalladditionalcasingisbaseduponexpectedreservoirconditionsaswellascompletionandstimulationtechniquesthataretobeused.Thissecond(orthird)setofsteelcasingprovidesadditionalisolationofthehydrocarbonzonefrompotentialshallowaquifers.
Itisimportanttorecognizethattheoilandgasindustryusestechnologicallyadvancedcementtoconstructthewellbore.Concreteusedforsidewalksisverydifferentthanthecementusedtosecuresurface,intermediateandproductioncasinginplace.Cementsaretailoredtoformation,temperature,depth,completiontechniqueandotherfactors.
CSUR Casing Model
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Casing and Cement
Itisimportanttoensurethatgroundwaterisprotected,notonlyinthefirstfewstagesofwellboreconstruction,butalsoduringthefulllifecycleofthewell.Thisisaregulatedprocesswherebytheownerofthewellisrequiredtoensurethatconditionsdownholedonotdegradethewellboreintegrityovertime.Possiblewellintegrityconcernscouldariseasaresultofpoorcementbond,casingshift,corrosionofcasingovertime,etc.Thereareseveraldiagnostictoolsutilizedinindustrytohelppromotewellboreintegritysuchascathodic protection,chemicaltreatmentandproductionpackers.Therearealsoseveraltoolstoidentifywellboreintegrityissuesafterthey’veoccurred,forexample,corrosionlogs,cementbondlogs,productionlogsandcasingpatches.
Gas-rich shale
SandstoneSandstone
LimestoneLimestone
HYDRAULIC FRACTURING
Shallow groundwater aquiferDeep groundwater aquifer
Protective steel casing:Steel casing and
cement provide wellcontrol and isolate
groundwater zones
Municipal water wellPrivatewell
Surface gas-well lease
Horizontal bore
Induced shale fractures
Note: Buildings andwell depth not to scale
1,000m
Surface
2,000m
2,300m
1,500m
Source: Canadian Natural Gas
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Completions and Stimulation
Oncethewellhasbeendrilledandcaseditisnowreadytobestimulated.Thereareavarietyofstimulationprocesses,themostcommonofwhichbeinghydraulicfracturing.Followingthestimulationofthepotentialzone(s)thewellisreadytobeequippedforproduction.
Whenthewellisready,hydrocarbonscanbeproducedeitherthroughtheproductioncasingorthroughtubinginserteddowntheproductioncasing.Thetypeofhydrocarbonsproduced(oilorgas)willdeterminethetypeofproductionstringused.
Iftubingistobeused,thejointsarelinkedtogetherwithcouplingstomakeupatubingstring.Tubingisrunintothewellmuchthesameascasing,buttubingissmallerindiameterandisremovable.Coiledtubingcanalsobeusedthuseliminatingtheneedfortongs,slips,orelevators,whichmakesiteasiertoinstall.Priortoproductionflow,downholeisolationequipmentsuchaspackersorplugsareremovedanddrillingfluidisflushedfromthewellbore.Hydrocarbonscannowflowfreelytothewellhead.
Ifthewelldoesnotflowonitsown,artificialliftsystemsmayneedtobeconsidered,suchasabeam pumping unit.
Beam Pumping Units. Source: United States Department of Labour
Coil Tubing UnitSource: Schlumberger
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Key Personnel
Completions and Stim
ulation
Thedrillingofanoilorgaswellrequiresanumberofhighlytrainedprofessionals,bothintheofficeaswellasinthefield.Keypersonnelmayincludebutarenotlimitedto:
Drilling Engineersdesignandimplementprocedurestodrillwellsassafelyandeconomicallyaspossible,whileatthesametimeprotectingthehealthandsafetyofworkersandotherpersonnelinaccordancewithestablishedregulations.
Surface Land Menensurethetimelyandaccurateacquisitionofsurfacerights;coordinatingtheeffortsofSurveyorsandBrokers.TheyrepresentthedrillingcompanyandinteractextensivelywithinternalBusinessUnits,publicandregulatorystakeholders.TheyalsomakesuresurfaceacquisitionandconsultationcompliancemeetRegulatoryrequirements.
Surveyorsdeterminethepreciselocationoftheplannedwellthesurroundingleasesite.Heorsheislicensedbytheprovinceandworkonbehalfoftheoilandgascompany
AConstruction Engineerperformsengineeringworkinthefieldtosupportwellconstructionandhelpsintheplanningandexecutionofconstructionworkinthefield.
ContractorsorSub-Contractorsareemployedbytheoilandgascompanytoperformworkonsitethroughoutvariousstagesduringwellconstruction.Thedrillingcrew,cementers,welltesters,waterhaulersandweldersareallexamplesofcontractorsthatworkontheconstructionsite.
Well site geologistsmonitortheprogressofthewellasitisdrilledtoidentifythepresenceofoilandgasinthesubsurface.Theyalsoinformtherestofthedrillteamwhenthewellhasreachedthereservoirtarget.
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Site Maintenance
FootprintCommercialproductionofunconventionalresourcesoftenrequiresnumerouswellstointersecttheoilandgasbearingformation(s)inordertobeeconomic.Thetechnologiesofhorizontaldrillingandmulti-stagefracturestimulationcoupledwithmultiplewellsfromasinglepadhaveenabledthecumulativesurfacefootprinttobeminimized.
Companiescandrillmultiplewellsfromasingle-padlocationandextractthehydrocarbonsfromasmuchas10sqkm.Whilethesizeofamulti-wellpadisslightlylargerthanaregularoilandgasleasethecumulativefootprintforadevelopmentismuchsmallerthanitwouldbewithconventionaldevelopmentusingverticalwells.Feweraccessroadsandtheconcentrationoffacilitiesandpipelineswithinthepadfootprintminimizethesurfacedisturbanceofadevelopment.
Duringtheactualdrillingandhydraulicstimulationproceduresforunconventionalresourcedevelopment,thereisaconcentrationofheavyequipmentonsite.Waterrequirementsforbothdrillingandfracturingcanbelargeandcommonlyalinedreservoirpitortanksareusedforstorage.Insomecases,ifthewatersourceisnearby,temporarypipelinesareconstructedtotransportthewaterratherthanusingtankertrucks.Uponcompletionofthedrillingactivities,alloftheheavyequipmentisremovedandpermanentsurfacefacilitiesareconstructed.Inmostcases,thefootprintofthewellsandsurfacefacilitiesismuchsmallerthantheoriginaldrillingfootprint
Construction vs. ProductionOncethewelliscompletedandfullymovedthroughtoproduction,thefootprintoftheleasesiteisgreatlyreduced.
Multi-well pad during construction and completions activity
Horizontal multi-well pad in productionSource: Trident Exploration
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Site Maintenance
Well ControlProperlytrainedpersonnelareessentialforwellcontrolactivities.Wellcontrolconsistsoftwobasiccomponents:anactivecomponentconsistingofspecializeddrillingfluidsandpressurecontroltominimizethepotentialinflowofhydrocarbonsorgroundwaterfluidsandapassivecomponentthatconsistsofmonitoringequipmentthatrespondsifainfloworpressurekickoccurs.TheBlowoutPreventer(BOP)isanintegralpartofthemonitoringandwellcontrolequipment.
Thefirstlineofdefenseinwellcontrolistohavesufficientdrillingfluidpressureinthewellbore.Inthesubsurface,undergroundfluidssuchasgas,wateroroilareunderpressure(formation pressure).Thecolumnofdrillingfluidinthewellcreatesapressure(mud pressure)thatcounteractstheformationpressure.Iftheformationpressureisgreaterthanthemudpressure,thereisthepossibilityofablowout.
Theblowout preventer (BOP),accumulator andchoke manifold areinstalledbytherigcrewafterthesurfacecasingissetandcemented.Thechokelinevalveisusedtoredirectthemudfromthewellboretothechokemanifoldshouldapressureeventoccur.Ifaneventdoesoccur,theBOPisactivated,containingthepressureandavoidingablowout.
TheBOPs,accumulators,andchokemanifoldneedtobeproperlymaintainedandaretestedonaregularbasis
Blowout Preventer (BOP)
Choke Manifold
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Glossary and Terminology
Accumulator:Adeviceusedinahydraulicsystemtostoreenergyor,insomeapplications,dampenpressurefluctuations.Wellpressure-controlsystemstypicallyincorporatesufficientaccumulatorcapacitytoenabletheblowoutpreventertobeoperatedwithallotherpowershutdown.
Aquifers:Anywater-bearingformationencounteredwhiledrilling.Drillersoftenareconcernedaboutaquifersandarerequiredtotakespecialprecautionsinthedesignandexecutionofthewellplantoprotectfreshwateraquifersfromcontaminationbywellborefluids.
Beam Pumping Unit:Anartificial-liftpumpingsystemusingasurfacepowersourcetodriveadownholepumpassembly.
BOP (Blow Out Preventer):Alargevalveatthetopofawellthatmaybeclosedifthedrillingcrewlosescontrolofformationfluids.Byclosingthisvalve(usuallyoperatedremotelyviahydraulicactuators),thedrillingcrewcanregaincontrolofthereservoir.
Casing:Large-diameterpipeloweredintoanopenholeandcementedinplace.Thewelldesignermustdesigncasingtowithstandavarietyofforces,suchascollapse,burst,andtensilefailure,aswellaschemicallyaggressivebrines.
Cathodic Protection:Atechniqueusedtominimizetherateofcorrosionofastructure.Itdoesnoteliminatecorrosion,ittransferscorrosionfromthestructureunderprotectiontoaknownlocationwhereartificialanodes(platesormetalbars)areplacedandcouldbereplacedeasily.
Cellar:Adug-outarea,possiblylinedwithwood,cementorverylargediameterpipe,locatedbelowtherig.Thecellarservesasacavityinwhichthecasingspoolandcasingheadreside.Onsmallerrigs,thecellaralsoservesastheplacewherethelowerpartoftheBOPstackresides.
Cement Bond Logs:Arepresentationoftheintegrityofthecement,usedincasingofthewell.
Choke Manifold:Asetofhigh-pressurevalvesandassociatedpipingthatusuallyincludesatleasttwoadjustablechokes,arrangedsuchthatoneadjustablechokemaybeisolatedandtakenoutofserviceforrepairandrefurbishmentwhilewellflowisdirectedthroughtheotherone.
Drill Bit:Thetoolusedtocrushorcutrock.Everythingonadrillingrigdirectlyorindirectlyassiststhebitincrushingorcuttingtherock.
Drilling Fluid:Anyofanumberofliquidandgaseousfluidsandmixturesoffluidsandsolids(assolidsuspensions,mixturesandemulsionsofliquids,gasesandsolids)usedinoperationstodrillboreholesintotheearth.
Drill String:Apipemadeoflengthsofsteeltubingthatisattachedtothedrillingtoolandrotatesduringdrilling.Thedrillingfluidpassesthroughthecentreofthedrillstringthroughthebitwhichisattachedattheend.
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Glossary and Term
inology
Formation Evaluation Tools:Thetoolsusedforthemeasurementandanalysisofformationandfluidproperties.Formationevaluationisperformedtoassessthequantityandproducibilityoffluidsfromareservoir.Formationevaluationguideswellsitedecisions,suchasplacementofperforationsandhydraulicfracturestages,andreservoirdevelopmentandproductionplanning.
Formation Fluids:Anyfluidthatoccursintheporesofarock.Stratacontainingdifferentfluids,suchasvarioussaturationsofoil,gasandwater,maybeencounteredintheprocessofdrillinganoilorgaswell.Fluidsfoundinthetargetreservoirformationarereferredtoasreservoirfluids.
Formation Pressure:Thepressureoffluidswithintheporesofareservoir,normallyhydrostaticpressure,orthepressureexertedbyacolumnofwaterfromtheformation’sdepthtosealevel.
Geophysical Logs:Alogofelementalconcentrationsfromwhichthegeochemistryoftheformationmaybederived.
Hydrogen Sulfide (H2S):AnextraordinarilypoisonousgaswithamolecularformulaofH2S.Atlowconcentrations,H2Shastheodorofrotteneggs,butathigher,lethalconcentrations,itisodorless.H2Sishazardoustoworkersandafewsecondsofexposureatrelativelylowconcentrationscanbelethal,butexposuretolowerconcentrationscanalsobeharmful.TheeffectofH2Sdependsonduration,frequencyandintensityofexposureaswellasthesusceptibilityoftheindividual.
Kelly:Alongsquareorhexagonalsteelbarwithaholedrilledthroughthemiddleforafluidpath.Thekellyisusedtotransmitrotarymotionfromtherotarytableorkellybushingtothedrillstring,whileallowingthedrillstringtobeloweredorraisedduringrotation.
Mud Pressure:Thepressureofthecolumnofdrillingfluidinthewellbore.
Packer:Adevicethatcanberunintoawellborewithasmallerinitialoutsidediameterthatthenexpandsexternallytosealthewellbore.
Perforating Gun:Adeviceusedtoperforateoilandgaswellsinpreparationforproduction.
Rigging-up:Tomakereadyforuse.Equipmentmusttypicallybemovedontotherigfloor,assembledandconnectedtopowersourcesorpressurizedpipingsystems.
Rig Mat:Aportableplatformusedtosupportequipmentforconstructionandresource-basedactivitiesincludingdrillingrigs,camps,tanks,helipads,etc.Italsoincludesastructuralroadwaytoprovidepassageoverunstableground,pipelinesandmore.
Canadian Society for Unconventional Resources (CSUR)Suite 420, 237 - 8th Avenue SECalgary, AB T2G 5C3
Phone: 403-233-9298; Toll Free: 1-855-833-9298Email: [email protected]; Web: www.csur.com