简介:ZhongyuanoilfieldsaremainlylocatedinDongpudepression,wherethegeologicalconditionswereextremelycomplicatedandtheexternalstressisabnormallyhigh,thepipeusedmayfailintheradialdirectionowingtowellshrinkagecausedbythecreepofsaltrock,leadingcatastrophiceconomicloss.Thereforethisregionhasbeenwellkownasatouchstoneforhighcollapseresistancecasingsincelongbefore.Inordertosatisfytherequirementforhigh-collapsestrengthcasingowingtothecreepofsaltbedstratuminDongpuDepressionregion,BG140TT,BG150TTandBG160TThigh-strengthcollapseresistancecasingseriesweredevelopedtobettercopewiththeseveregeologicalconditions.Amongthecasingseries,aBG160TTnon-APIspecificationcasingwithcollapsestrengthnotlessthan170MPawereprepared.Uptopresent,allthesehigh-strengthcollapseresistancecasinghavebeensuccessfullyappliedintheDongpuDepressionregion.Theresearchconcept,mechanicalproperties,aswellasapplicationresultwereintroducedinthispaper.