X80管線鋼環(huán)焊縫焊接殘余應(yīng)力數(shù)值模擬.pdf

1、天津大學(xué)碩士學(xué)位論文X80管線鋼環(huán)焊縫焊接殘余應(yīng)力數(shù)值模擬姓名：劉志毅申請學(xué)位級別：碩士專業(yè)：材料加工工程指導(dǎo)教師：李午申20080601ABSTRACTLargecaliber&highvoltagetransmissionandtheuseofhigh—levelpipelinesteelisaninevitabletrendintheinternationalpipelineprojectdevelopmentThroughthe

2、useofhighgradepipelinesteelwhichcouldincreasepressureontransportation(naturalgas)，enhancingtransmissionefficiencyandthinningpipelinewallthickness，reducingconsumptionofthecorrespondingweldingmaterials，therebysavingtheinve

3、stmentonthepipelinesbuildingHowever，thehigherlevelofpipelinesteelintensity。thegreatertheresidualstresses，itisnecessarytounderstandthesIZeanddistributionoftheresidualstressesandthustocontrolresidualstressX80Pipelineisthec

4、ontrolledrollingandcoldalloysteelIthasthehighstrengthandgoodantiductilefractureperformance，anditisthehigh。gradesteelofincreasinglyextensiveapplicationintransmittinggaspipelineThetopicswhichstudytheX80pipelinesteelisbased

5、onmetalphysics，mechanicsandweldingheattransferandotherbasictheorySimulatingthexa0pipelinesteelburjointweldingthermalandstressfieldbythemeansofacombinationwiththephysicsexperimentsandnumericalsimulationApplicatingSYSWELDp

6、rojectfiniteelementanalysissoftwareandusingadualellipsoidheatsourcemodeltakingintoaccountthethenon’linearrelationshipofheatphysicalpropertiesandtemperature，aswellastheimpacttotemperaturefieldwhichthelatentheatofthephaset

7、ransitionlead，simulatingthemulti1ayerweldingprocessofX80pipelinesteel，gettingtheheatcyclecurveofcoarsegrainareaofHAZunderthedifferentweldingprocessparameters，andimplementingthethreecouplingofweldingtemperature，organizati

8、onalstatusandstressstrainfieidGettingthedistributionandchangesofweldingresidualstressunderadifferentweldingprocessparametersbythenumericalsimulationLayingthefoundationforfurthercouplingcalculationtothespreadandtheconcent

9、rationoflocalhydrogeninweldedjointsInadditionfiringanalysisthelinearrelationshipofresidualstressabouttheweldingheataffectedzoneweldingcenterandweldinglineenergy，thepreheatingtemperaturebyusinglinearregressionanalysis，the

10、resultshowsthelinearrelationshipbetweenlargestresidualstressandweldinglineenergy，preheattemperatureAvarietyoffactorsontheimpactofresidualstressarerevealedatthemacro，whichprovidthetheoreticalbasisforoptimizingtheweldingpr