基于等效弯曲变形能的通井底部钻具组合设计和评价方法

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中图分类号：TE21 文献标志码：A

Abstract：Casingused inoiland gaswelsisusuallyoflargeouterdiameter，thinpipewallandhigh stifess，whichcan makeits unning downoperation verydificult andcomplex withunexpected obstructions.Especialy，when thecasing anulusclearanceissmall，large boreholecurvatureorany iregularwelbore maycause highrunning resistance，making thecasing runningoperation morecomplicated.Infield practice，atrippng botomhole assembly（BHA）isoftenused tocorrecthe wellbore，smooththeboreholewall，and prepare forasmooth running of thecasing string.Thedesignandstructureof the tripping BHAare important forits functionand performance.Inthis study，anewdesignandevaluation methodof he tripping BHA was proposed.Firstly，a static modelof the tripping BHA and casing string was established.Then，according to continuityandboundaryconditions，thespatialconfigurationof thetrippngBHAandcasing string inactual welbore wasfigured outbased ona weighted residual method，andthe deformation energy ofthetrippng BHA and casing string with the samelength wascalculatedandcompared.Finaly，an evaluation methodof thetripping BHA basedonequivalentstffnes was formulated torealize thedesignofanew tripping BHA.Theresults show thatareasonable tripping BHA should havea goodoperation effectforsmallholesize，but fora wellwithlarge holesize andsmallcasing-wellbore clearance，the tripping BHA maystillhaveapooroperation effect，and therefore itisnecessarytouseareamer toenlarging theborehole.

KeyWords： tripping BHA；casing string；actual wellbore;；energyof bend deformation；equivalent stifnesscoefficient

钻井作业完成后，通常利用弯曲刚度较大的底部钻具组合（bottomholeassembly，BHA）进行通井作业，这种BHA被称为通井BHA。（剩余10579字）