内压作用下含裂纹射孔套管临界开裂应力分析.pdf

《内压作用下含裂纹射孔套管临界开裂应力分析.pdf》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、石油机械一22一CHINAPETROLEUMMACHINERY2012年第40卷第4期●钻井技术与装备内压作用下含裂纹射孔套管临界开裂应力分析许爱荣邹云杨向同窦益华(1．西安石油大学机械工程学院2．中国石油塔里木油田公司工程院)摘要：为了了解内压作用下含裂纹射孔套管临界开裂应力，为现场确定泵压等施工参数提供参考依据，用ANSYS有限元分析软件建立了射孔套管有限元模型，给出了含孔边裂纹射孔套管应力强度因子计算公式，对内压作用下含裂纹射孔套管临界开裂应力进行分析计算，得到了临界开裂应力与纵向裂纹长度的关系曲线。研究结果表明，套管最大应力集中在孔边裂

2、纹处，在内压产生的应力作用下裂纹有可能沿轴向产生脆性扩展，因此，孔边裂纹大大削弱了射孔套管的强度；射孔套管临界开裂应力随裂纹长度的增加而减小；在短裂纹区(10mm

3、alCrackingStressofPerforatedCasingwithCracksundertheEffectofInternalPressureXu5irongZouYunYangXiangtongDouYihua(1．CollegeofMechanicalEngineering，Xi’anShiyouUniversity2．EngineeringResearchInstituteofPetroChinaTarimOieldCompany)Abstract：Tounderstandthecriticalcrackingstressofp

4、erforatedcasingwithcracksundertheeffectofinternalpressure，thefiniteelementANSYSsoftwarewasadoptedtoestablishthefiniteelementmodelofperforatedcasingSOastoprovidethereferencefordeterminingoperatingparameterssuchaspumppressure．Thecalculationformulaforstressintensityfactorofperf

5、oratedcasingwithhole—edgecrackswasgiven．Thecriticalcrackingstressofperfora—tedcasingwithcracksundertheeffectofinternalpressurewasanalyzed．Therelationcurvebetweencriticalcrack—ingstressandlongitudinalcracklengthwasobtained．Thefindingsshowthatthemaximumstressofcasingconcert—tr

6、atesonhole-edgecracks．Undertheeffectproducedbyinternalpressure，itispossibleforcrackstomakeanaxi—albrittleexpansion．Therefore，hole—edgecracksremarkablyweakenthestrengthofperforatedcasing．Thecriticalcrackingpressureofthecasingdecreaseswiththeincreaseofcracklength．Inthezoneofsh

7、ortcracks(10him

8、；hole—edgecrack；internalpressure；criticalcrackingstress；cracklength；stressi