【7A文】钻井工程英文课件1.5 Costs， Problems.ppt

《【7A文】钻井工程英文课件1.5 Costs， Problems.ppt》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、1DrillingCostandHoleProblems1.5-121.5-2TheDrillingCostEquation:Cf=drillingcost,$/ftCb=costofbit,$/bitCr=fixedoperatingcostofrig,$/hrtb=totalrotatingtime,hrstc=totalnon-rotatingtime,hrstt=triptime(roundtrip),hrs=footagedrilledwithbit,ftEq.1.1631.5-3DrillingCosts

2、Tendtoincreaseexponentiallywithdepth.Thus,whencurve-fittingdrillingcostdata,itisoftenconvenienttoassumearelationshipbetweentotalwellcost,C,anddepth,D,givenbyC=aebD…………………..(1.17)4Fig.1-65.Least-squarecurvefitof1978completedwellcostsforwellsbelow7,500ftinthesout

3、hLouisianaarea.1.5-451.5-5DrillingTimecont’dPlottingdepthvs.drillingtimefrompastdrillingoperations:A.AllowsmoreaccuratepredictionoftimeandcostfordrillinganewwellB.Isusedinevaluatingnewdrillingprocedures(designedtoreducedrillingtimetoagivendepth).61.5-6BitWeight

4、andRotarySpeedIncreasingbitweightandrotaryspeedboostsdrillingrateTheseincreasesacceleratebitwearFieldtestsshowthatdrillingrateincreasesmoreorlessindirectproportiontobitweight7Consider10”hole(don’toverdo!!)DrillingRate,ft/hrBitWeightx1,000lb/in40,000lbf1.5-78Dri

5、llingRate,ft/hrRotarySpeed,RPMDon’toverdo!Casingwear,bitlife...1.5-89DrillingRate,ft/hrHydrostaticPressure,1,000’sofpsiEFFECTOFBACKPRESSURE0-5,000psi1.5-910Depth,ftRotatingTime,hoursEFFECTOFDRILLINGFLUIDwatervs.air1.5-1011EFFECTOFSOLIDSINTHEMUD1.5-11121.5-12Hol

6、eProblemsLostCirculationStuckPipeKeyseat-CrookedHoleDifferentialStickingMechanicalStickingJunkinHoleKicksandBlowoutsCrookedHole131.5-13HoleProblems-LostCirculationFlowout

7、idCharacteristicsInducedFracturingofFormationFromRapidPipeMovementCauses:HighFormationPermeability(e.g.fractures)LowFormationPorePressure1.5-14HoleProblems-LostCirculation15CostlyMudMakeupLossofProductionFireLossofPermittoDrillResults:1.5-15HoleProblems-LostCir

8、culation16PreventiveMeasures:CrewEducationGoodMudProgramStudyWellsinArea…tobeprepared1.5-16HoleProblems-LostCirculation17UseLostCirculationMaterialasMudAdditive(fibrousorgra