海上油田注水井液控式环空安全封隔器的研制与应用

海上油田注水井液控式环空安全封隔器的研制与应用

刘红兰

【摘要】针对埕岛油田现有环空安全封隔器无洗井通道因而难以满足开发要求的问题,在分析国内外环空安全工具优缺点的基础上,研制了具有2条独立液路(分别控制洗井和坐封机构)的液控式环空安全封隔器.该封隔器的顶部液路控制洗井机构,液压强制开启洗井,液控管线泄压后由双重弹簧控制滑套,强制关闭;中部液路与底部液路相通,控制该封隔器与管柱油层部位的分层液控封隔器同时坐封;该封隔器设计有坐封锁紧机构,在紧急情况下,液控管线意外泄压胶筒也不回缩,以达到控制环空安全的目的.基于三维井眼中管柱受力分析计算模型,根据环空安全工具的下入深度,确定了洗井结构中心管的抗拉强度,并对液控式环空安全封隔器的性能进行了分析验证.该封隔器在42口注水井进行了现场应用,结果表明,完成坐封后的滑套多次洗井作业,套压始终为0 MPa,可有效保护海洋生态环境.研究认为,液控式环空安全封隔器不仅可以解决埕岛油田现有环空安全封隔器无法解决的问题,也可以满足其他海上油田安全环保开发的要求.%Without flushing channels,the conventional annular-safe packers used in the Chengdao Oilfield can hardly satisfy demands for adequate oilfield development.By analyzing the annular-safe tools in China and around the world,the hydraulic annular-safe packer with two independent hydraulic channels (for control over flushing and seating devices,respectively) has been developed.The hydraulic system in the top section of the packer can be used to control the over flushing devices:and flushing operations can be initialized under control of hydraulic pressure.Upon pressure release in hydraulic control pipelines,dual springs can be initialized to control the slip sleeve and close the system.The

hydraulic system in the central part is connected with that in lower parts.Jointly,they may control the simultaneous seating of packer and the packer for layered injection in reservoir sections of the pipe string;The innovative packer is equipped with locking mechanism for seating.Under emergency conditions,the rubber barrel may not retract even in circumstances with accidental pressure releasing.In this way,the annular safety can be guaranteed.Upon successful development of the hydraulic annular-safe packer,calculation model for stresses on pipe string in 3D wellbore have been used to determine tensile strength of the central pipe in accordance with setting depths of annular-safe tools.During this research,the performance of the new hydraulic annular-safe packer has been reviewed prior to the application in 42 water injectors on site.Field application performances show that properly seated slip sleeves can effectively maintain casing pressure at 0 MPa after multiple flushing operations.Generally speaking,the innovative packer can provide effective protection over marine environments.Research results show that this hydraulic annular-safe packer can effectively solve problems in existing annular-safe packers in the Chengdao Oilfield.In addition,the newly-developed packer can satisfy demands for development of other offshore oilfields in safe and environment-friendly manner.

【期刊名称】《石油钻探技术》

【年(卷),期】2017(045)005

【总页数】5页(P103-107)