Compared with conventional oil and gas extraction,shale gas extraction mainly involves high inclination and horizontal wells,with more than 20 perforation completion sections.At the same time,the casing also undergoes alternating loads such as pulling,pressing,and squeezing underground,and the working conditions are harsh.Therefore,the BT135VRE shale gas casing is designed and developed,and the physical and chemical properties,microstructure,thermal stability,collapse resistance at room temperature and high temperature were also studied.The results show that the yield strength of BT135VRE is more than 965 MPa and the transverse impact energy at 0℃is more than 100 J by proper heat treatment,and the material also has good thermal stability and high temperature collapse resistance at high tem-perature,thus realizing the comprehensive requirements of high strength and toughness,which meets the requirements of shale gas produc-tion conditions.
BT135VREhigh temperature collapse resistancehigh strength and high toughnessshale gascasing