《Chapter 12 - Deepwater “Riserless” Drilling.docx》由会员分享，可在线阅读，更多相关《Chapter 12 - Deepwater “Riserless” Drilling.docx（40页珍藏版）》请在课桌文档上搜索。
1、CHAPTER12DeepwateruRiser1.essnDri1.1.ingNote:Theseoperatingsectionsarenotdefinitiveguides.Regiona1.know1.edgeandexperiencesha1.1.a1.waysbeapp1.iedtoassurebestwe1.1.practiceisused.GEo1.OGY,GEoSCIENCE,ANDPRESSUREMANAGEMENTGenera1.Ear1.ierchaptersintroducedtheessentia1.aspectsanddifferenceofdeepwaterwe
2、1.1.sversusthestandardoffshorenormsforbestpractice.Precedingchaptersattendtooperationa1.aspectsstartingwiththeriser1.esssections.Tbbeusedinconjunctionwiththeoperationa1.chapterstoassurenostoneis1.eftunturned,itisrecommendedthatreadersaffordthemse1.vesaccessibi1.itytothevariousdeepwaterIADC,API,andIn
3、ternationa1.oi1.andgasproducers(IOGP)standards,bestpracticesguide1.ines,andtechnica1.documentsthathaveresu1.tedfromvariousjointindustryprojectsandinitiatives.TheRiser1.essPhasesWiththevesse1.andpeop1.eonboardpreparedandreadytocommenceoperationsatadeepwater1.ocation,asout1.inedinChapter1.ztheriser1.e
4、ssphasesandoperationa1.sequenceindeepwatersha1.1.inc1.ude:1. Pi1.otho1.eandpenetrationtestatasafedistancefromthemainwe1.1.1.ocationifrequired.2. Spuddingthemainwe1.1.ontheseaf1.oor,i.e.,withatypica1.errorto1.eranceof1-3m.3. Insta1.1.ationoffoundation(inu1.trasoftformations)and/oraconductorcasingstri
5、ngs,insofttomediumc1.ayconditionstotherequiredstructura1.depth(Fig.12.1).4. Dri1.1.ing,tripping,insta1.1.ing,andcementingthesurfacecasingstringsor1.inerstosubsurfacedesignandengineereddepthtoaffordrunningthesubseaBOPandmarineriserandthefirstintermediatesectiontoitsoptima1.designdepth.Notes:Thefina1.
6、surfacestringcontainsthehigh-pressurewe1.1.headhousing(HPWHH)thatengagesand1.ockstoorispre1.oadedtorigidizewiththe1.PWHH.We1.1.contro1.mustbeassuredthroughoutthisphasewiththenecessarycontingentcasingsandoperatingp1.ansinp1.acetomeetunknownhazardsthatcanariseandanyoperationa1.cha1.1.engesorchangesreq
7、uired.Ivpuucnofc1.ayandsi1.tpartic1.esMar1.Mr1.1.essthan4mRocksIofTnedfromanaccumu1.ationofc1.yminera1.sandca1.citeSi1.tstoneS1.st4to60mRocksformedfromanaccumu1.ationofminera1.grains(quartz)SandstoneSst60mto2mmSafK1.stonecomp6in(150mm)“dropstones”or1.argerbou1.dersexistthatcannotbecircu1.atedfromthe
8、we1.1.boreoncedri1.1.ed,inthiscase,operatingconditionscandisp1.ayerratictorque/dragduringrotatingandmovingpipe.Hereitisconsideredbestpracticetos1.owdownandworkthepipethroughthesesections.Roughdri1.1.ingcanadditiona1.1.yresu1.tduetotheinherentinterbeddedandvariab1.enatureofformationsandcoarserconstit
9、uentsthatexist.Ina1.1.suchcircumstances,dri1.1.ersmustbepreparedtostoprotation,andnotunwitting1.ybackreamasamatterofcourse,butmustfu1.1.yunderstandandappreciatethemostpurposefu1.approachtoreso1.veeachsituation.E.g.:stoprotation,pickupoffbottom,changeparametersbys1.owingrotary,increasingweightand/orp
10、umpingfarmorefrequentand1.argersweeps.ImportanceofPressureWhi1.eDri1.1.ingToo1.sTheprovisionofanannu1.arpressurewhi1.edri1.1.ingtoo1.(APWDorPWD)inthesesectionsisessentia1.asthisprovidespreciseandaccuratephysica1.we1.1.boreeva1.uationofcumu1.ativedownho1.eequiva1.entmudweight(EMW)andannu1.arwe1.1.bor
11、epressuresresu1.tingwitheachfootdri1.1.ed.Physica1.rea1.-timewe1.1.conditionsthatarere1.ayeddirect1.ytothesupervisors,dri1.1.ers,andmud1.oggerstoassurecorrectiveactionsandchangescanbemadeimmediate1.yasneeded.E.g.zifhighEMWtrendsresu1.t,best-practicesresponsescanbediscussedandinitiatedtocombatdownho1
12、.ewe1.1.boreconditionstopreventprob1.emsesca1.ating.Converse1.ywhenoperatingwindowsofopportunitiesexist(examp1.e:whendri1.1.ing100%c1.ayinterva1.s),greatereffectivenessandefficienciescanresu1.tuti1.izingPWDtoo1.sthroughoutcomes,benefitsandva1.uegained.Riser1.ess“C1.ayandSandEngineeringI1.1.ustrative
13、Examp1.eTheworkedexamp1.epresentedservestopresentagenera1.izedout1.ookoftypica1.downho1.eriser1.essoperatingwe1.1.boredri1.1.ing1.imits(a26-inwe1.1.boreinthiscase)thatcou1.dexistatapointintimeatadepthconsideringbotha100%c1.ayor100%sandisbeingdri1.1.ed.Graphica1.resu1.tspresent(forpenetrationandpumpr
14、atesasshown)todemonstratec1.ayandsand1.imitsthatexist.26-inwe1.1.bore,dri1.1.ing2700m(2000-nwaterdepth)ROPfVhFormationporosity %Formationdensity F d 1.bgalTransportefficiency Te %F1.owrate Q, gal/min(1.6u=su。一 1osWorksheetdatainput=Averageporosityofformation(s)interva1.dri1.1.ed(%)note:Va1.uescanran
15、gefrom40%foraquartssandstonetoashighas80%forC1.aystonesattheseabed.C1.ayva1.uesthatthendecreasefarmorerapid1.ythansandwithdepth,buria1.1.ithification,etc.Fd=Formationdensityforc1.ays,si1.t,sand,etc.ROP=rateofpenetrationQ=dri1.1.ingpumpingf1.owratePPm=Padmudweightbeingpumpedequiva1.entdensitynotedats
16、urface.sing1.e:=10.3m(31ft)GEO1.Y,GEOSCIENCE,ANDPRESSUREMANAGEMENT447D=ho1.esizedri1.1.edd=dri1.1.stringdiameterstand:=31m(93ft)WG-ho1.een1.argementfactor%SI=section1.engthfromseabedtodepthifinterest:=30%2040-kgf 17 I1.bf 2220,菽= 18.51菽12ROP=:= 525350Q1.Q2IOOO例 min1600 皿 minP1.,m:=9.2曳 ga1.Dh265.875
17、Note:1.owerporositygenera1.1.ychosentomode1.maximum1.oadcase.W0:=100%SI:=700mDeterminesedimentannu1.ar1.oadingvo1.umesBasedonporosityho1.esizeandformationdensityinput.Steps#1,#2,determinecuttingsvo1.ume(Ah),concentration(Cd)pereva1.uated1.engthsdri1.1.ed.Note:fornoncircu1.atingconditions.Step#1:D
18、eterminethewe1.1.borevo1.umedri1.1.edforho1.esize,(Dh)zaverageporosity(%)zandvo1.umeperdistance(ftm)dri1.1.ed(asinput.Step#2:Ca1.cu1.atethesedimentorcuttingsconcentration(Cd)basedonthevo1.umeofcuttingsdri1.1.edandgeneratedbasedonwe1.1.borevo1.ume(Ah)andformationdensity(Fd)asinput.Cd:=Ah-Fd.=357.7ftS
19、tep#3:Convertthesedimentorcuttings1.oadingandon(Cd)intoamoremeaningfu1.yzasdri1.1.ed/zmetric,e.g.,perdri1.1.pipesing1.eoradri1.1.ingstand1.engthdri1.1.edbasedondataasinput.TransportefficiencySifferman,stransport rationsInversemud ve1.ocity, 1/ft/minStep#4:Determineannu1.arve1.ocities(Av)forf1.owrate
20、(s)(Q1zQ2),we1.1.borediameter(Dh)zdri1.1.string(dp),asinputtakingintoaccountestimatedwe1.1.boreen1.argement(Wo)Cd=6此Cd=18.2包sing1.estandr，,m= 14.6minAv2= 48- minStep#5:Tbbeab1.etouseSiffermanstab1.esonefirsthastodeterminetheinverseofannu1.armudve1.ocity(1.Av)tothenuseva1.ueobtainedinStep#6.工=0.033-=
21、0.021-i-AvftAv2ftminminStep#6:Usingva1.uesobtainedinStep#5,Siffermanstab1.escanbeusedasasimp1.emethodtoderiveatransportratiothroughp1.ottingtheinversemudve1.ocity(1.Av)andintersectingthis1.ineforase1.ecteddri1.1.ingf1.uidasshown.Transportratios(Et.%)thenobtainedbasedforeachpumpandannu1.arf1.owrate,b
22、asedonho1.esizeanddri1.1.stringgeometries,etc.asinput.Examp1.eoutputva1.ues(forwaterandathinf1.uid)astypica1.1.yusedintheriser1.esssectionbasedon1/Avand1.Av2inputsderivedarei1.1.ustratedbe1.ow.SeaWater:Ef1:=35%Ef2:=55%Ifweweretomode1.seawateratthef1.owratesinput.Onecanconc1.udethewe1.1.borec1.eaning
23、(transportefficiency)effectofthehigherf1.owandannu1.arve1.ocityoutcomesandbenefitspresented.Shou1.dwea1.soconsidera100%C1.ayand/or100%sandsequenceisdri1.1.ed.Thesetwocasesa1.onecanpresenttheoutermax/mindri1.1.ingboundary1.imitsthatcou1.dexist.Et1.iai1.d=35%E=55%EH.tey=70%Ef2叼:=85%Cuttingsconcentrati
24、onStep#7:Concentrationofdri1.1.edsedimentsorcuttings(Ca)inthewe1.1.boreisdeterminedforratesofpenetrationandparametersinputasfo1.1.ows;Note:theresu1.tspresenttheeffectsofdri1.1.ingROP,circu1.atingrate,dri1.1.stringho1.edimensionsforpumprateandtransportefficiencyasinput.ROP公(1一6一M一叫100cayQiROP不(1F)-(d
25、;-)Cac2:=100=Ef2dayQ2ROP/0F)-(d;-娟4ROP-(IN)-M-4)Ca.2:=Ef2sajQ2-1000.040.090.221.0915.270.020.040.110.567.860.090.170.442.1830.530.030.070.170.8712.14450Psand1.：= =1010.813.329.5294Ibfga1.Psand2：=F4 Cn$2 + Ppm - Q 一 2)=9.59.810.8Ibf17.3ga1.122.512.DEEPWATERmR1SER1.ESSDRI1.1.INGAnnu1.arpressure(fractu
26、re)effectsStep#8:Basedonva1.uesobtainedinStep#7.Equiva1.entannu1.armudweightforsandextremesinacanbedeterminedwithinthewe1.1.borefromconditiona1.dataasinput.Theoutputva1.uesthenusedtoeva1.uatethedri1.1.ingandfracture1.imitsforthewe1.1.shou1.dasandsectioninterva1.bedri1.1.ed.Step#9:Furtherdeterminestheannu1.arwe1.1.borevo1.ume,fortheactua1.section1.ength(SI)tobedri1.1.edtothedepthofinterestandaccountsforho1.een1
