Wellhead - Wikipedia, The Free Encyclopedia
-
Upload
bahrul-ulum -
Category
Documents
-
view
215 -
download
0
description
Transcript of Wellhead - Wikipedia, The Free Encyclopedia
-
24/2/2015 WellheadWikipedia,thefreeencyclopedia
http://en.wikipedia.org/wiki/Wellhead 1/3
Wellheadgasstorage,EtzelGermany
WellheadFromWikipedia,thefreeencyclopedia
Awellheadisthecomponentatthesurfaceofanoilorgaswellthatprovidesthestructuralandpressurecontaininginterfaceforthedrillingandproductionequipment.
Theprimarypurposeofawellheadistoprovidethesuspensionpointandpressuresealsforthecasingstringsthatrunfromthebottomoftheholesectionstothesurfacepressurecontrolequipment.
Whiledrillingtheoilwell,surfacepressurecontrolisprovidedbyablowoutpreventer(BOP).Ifthepressureisnotcontainedduringdrillingoperationsbythecolumnofdrillingfluid,casings,wellhead,andBOP,awellblowoutcouldoccur.
Oncethewellhasbeendrilled,itiscompletedtoprovideaninterfacewiththereservoirrockandatubularconduitforthewellfluids.ThesurfacepressurecontrolisprovidedbyaChristmastree,whichisinstalledontopofthewellhead,withisolationvalvesandchokeequipmenttocontroltheflowofwellfluidsduringproduction.
Wellheadsaretypicallyweldedontothefirststringofcasing,whichhasbeencementedinplaceduringdrillingoperations,toformanintegralstructureofthewell.Inexplorationwellsthatarelaterabandoned,thewellheadmayberecoveredforrefurbishmentandreuse.
Offshore,whereawellheadislocatedontheproductionplatformitiscalledasurfacewellhead,andiflocatedbeneaththewaterthenitisreferredtoasasubseawellheadormudlinewellhead.
Contents
1Components2Functions3Designspecification4Seealso5Externallinks
Components
Theprimarycomponentsofawellheadsystemare:
casingheadcasingspools
-
24/2/2015 WellheadWikipedia,thefreeencyclopedia
http://en.wikipedia.org/wiki/Wellhead 2/3
casinghangerspackoffs(isolation)sealsbowlprotectors/wearbushingstestplugsmudlinesuspensionsystemstubingheadstubinghangerstubingheadadapters
Functions
Awellheadservesnumerousfunctions,someofwhichare:
1. Provideameansofcasingsuspension.(Casingisthepermanentlyinstalledpipeusedtolinethewellholeforpressurecontainmentandcollapsepreventionduringthedrillingphase).
2. Providesameansoftubingsuspension.(Tubingisremovablepipeinstalledinthewellthroughwhichwellfluidspass).
3. Providesameansofpressuresealingandisolationbetweencasingatsurfacewhenmanycasingstringsareused.
4. Providespressuremonitoringandpumpingaccesstoannulibetweenthedifferentcasing/tubingstrings.
5. Providesameansofattachingablowoutpreventerduringdrilling.6. ProvidesameansofattachingaChristmastreeforproductionoperations.7. Providesareliablemeansofwellaccess.8. Providesameansofattachingawellpump,
Designspecification
Theoilindustryspecificationsforwellheadsystems(materials,dimensions,testproceduresandpressureratingsetc.)are:
1. API6ASpecificationforWellheadandChristmasTreeEquipment2. ISO10423WellheadandChristmasTreeEquipment
Ingeneralwellheadsarefivenominalratingsofwellheads:2,3,5,10and15(x1000)psiworkingpressure.Theyhaveanoperatingtemperaturerangeof50to+250degreesFahrenheit.Theyareusedinconjunctionwithringtypesealgaskets.
Ingeneraltheyieldstrengthofthematerialsrangefrom36000to75000psi.
-
24/2/2015 WellheadWikipedia,thefreeencyclopedia
http://en.wikipedia.org/wiki/Wellhead 3/3
WikimediaCommonshasmediarelatedtoWellheads.
Seealso
PutealWaterwellheadPumpjackAmericanPetroleumInstituteDrillingrig(petroleum)Christmastree(oilwell)
Externallinks
SchlumbergerOilfieldGlossary:wellhead(http://www.glossary.oilfield.slb.com/Display.cfm?Term=wellhead)
Retrievedfrom"http://en.wikipedia.org/w/index.php?title=Wellhead&oldid=606468562"
Categories: Oilwells Oilplatforms Petroleumproduction Oilfieldterminology
Thispagewaslastmodifiedon30April2014,at12:39.TextisavailableundertheCreativeCommonsAttributionShareAlikeLicenseadditionaltermsmayapply.Byusingthissite,youagreetotheTermsofUseandPrivacyPolicy.WikipediaisaregisteredtrademarkoftheWikimediaFoundation,Inc.,anonprofitorganization.