【作者】 张梅；

【导师】 方华；

【作者基本信息】 大庆石油学院 ， 化工过程机械， 2008， 硕士

【摘要】 石油是一种不可再生的资源,为了最大限度地提高石油采收率,大庆地区开辟了三元复合驱实验区。三元复合驱是属于三次采油的一种方法,可以使原油采收率比水驱提高20%~25%。由于它采用碱(NaOH)/表面活性剂/聚合物作为驱油剂,同时井下温度随着井深而增加,一般会达到100℃左右,所以在这种环境中工作的油管、抽油杆(部分材料为35Mn2钢)出现了较多的断管、断杆现象。目前,国内外对三元复合驱技术的研究还仅限于驱油效果,而对管材在其中的碱脆行为的研究报道甚少。因而,研究在热强碱介质中35Mn2钢的腐蚀机理可以为油管、抽油杆的合理选材以及采取有效防腐措施提供理论依据,同时也可降低安全事故的发生,为油田带来一定的经济效益和社会效益。此外,套管作为油气井的重要组成部分,要尽可能提高其抗射孔开裂的能力。由于对套管射孔时,管体需承受应变率极大的冲击载荷,当达到一定的临界条件时会发生失稳开裂,所以研究高应变率下碱脆对35Mn2钢动态断裂韧性K Id的影响可以为石油套管的安全使用提供一定的参考依据。本文通过电化学实验和冲击实验相结合的方法,在不同极化电位下研究了35Mn2钢冲击功AK V的变化规律,验证了氢致开裂是35Mn2钢碱脆的主要机理。并通过Hopkinson压杆实验证明了高应变率ε=103/s下,碱脆对35Mn2钢动态断裂韧性K Id的影响不大。更多还原

【Abstract】 The petroleum is one kind of non-renewable resources, in order to most effectively enhance the petroleum’s recovery ratio, Daqing area opens A-S-P experimental plot. A-S-P is a way of tertiary oil recovery technology. Compared to the water drive, A-S-P technique can make the petroleum’s recovery ratio be enhanced to 20%~25%. Because it uses alkali (NaOH) to drive the oil, and simultaneously along with the well depth, the subsurface temperature is increased up generally to 100℃. Therefore, working in this kind of environment, the oil tube, the oil extraction rod (part of materials are 35Mn2 steel) appear more broken phenomenon. At present, A-S-P technique is only studied to its effect of driving oil in domestic and foreign country. But research report is really few to the tube’s caustic brittlement’s behavior among ASP. Thus, studying 35Mn2 steel’s corrosion mechanism in the hot strong alkali medium may provide the basis for the reasonable material selected as well as the anticorrosion measure, simultaneously may reduce the security accident’s occurrence, also bring certain economic efficiency and the social efficiency for the oil industry.In addition, as the important part of oil and gas well, thimble’s anti-cracking should be improved in the process of perforation. Because of perforation, the body must withstand the impact load with an enormous strain rate. When certain critical condition can be achieved, thimble appears the cracking. Therefore under the high rate of strain, studying the caustic brittlement’s influence on 35Mn2 steel’s dynamic fracture may provide certain reference for the petroleum thimble’s safe handling.Through the electrochemistry experiment and the impact experiment, the article studies 35Mn2 steel’s impact ductility and proves that hydrogen-induced-cracking is 35Mn2 steel caustic brittlement’s main mechanism. Moreover, through the Hopkinson experiment, the caustic brittlement has little influence on the 35Mn2 steel’s dynamic fracture toughness under the high rate of strain.更多还原