我国海上油套管现状及发展趋势分析

Analysis of the current situation and developm ent trend of offshore oil casing in China

全球油气资源开发正在向超深水、超深井、大位移等复杂井转变,螺纹连接是油套管的主要连接方式,标准的API螺纹在保证井下管柱的结构完整性和密封完整性方面均存在不足,不能用在高压、高腐蚀等严酷环境下的油气井,而特殊螺纹具有较高的连接强度及抗变形能力,并具有良好的密封性能,可以应用于严酷条件的油气井。调研了我国四大海域油田特点,统计分析了我国海域油套管服役条件和历史使用现状,分析发现特殊螺纹设计的核心主要包括优化密封面、扭矩台肩和连接螺纹参数,降低应力集中、保证密封性能、减少塑性变形,发展适应于我国海上的特殊螺纹,并形成针对性标准对我国海上油套管发展具有重要意义。

Global oil and gas resources development is moving to ultra-deep water,ultra-deep wells,large displacement and other complex wells,threaded connection is the main connection method of oil casing,standard API thread in the guarantee of downhole pipe string structural integrity and sealing integrity are insufficient,and can’t be used in high pressure,high corrosion and other harsh environment of oil and gas wells,and special threads have high connection strength and deformation resistance,and has good sealing performance,can be applied to oil and gas wells under harsh conditions.The characteristics of China’s four major sea area oilfields were investigated,the service conditions and historical use status of oil casing in China’s sea area were statistically analyzed,and the analysis found that the core of special thread design mainly included optimizing the sealing surface,torque shoulder and connection thread parameters,reducing stress concentration,ensuring sealing performance,reducing plastic deformation,developing special threads adapted to China’s marine,and forming targeted standards for the development of offshore oil casings in China.