高含硫气井井下安全阀失效的对策及现场实践

Countermeasures Against Failure of Subsurface Safety Valve Used for A Highsour Gas Well and Their Application

井下安全阀是一种用于防止井喷、保证生产安全的井下工具。一般位于井口以下60~200 m的位置,通过地面的液压控制来实现井下安全阀的开启与关闭。它能够在地面生产设施出现异常情况时实现自动关闭,以防止不受控制的地层流体流到地面,作为灾难性事件发生的最后一道屏障,它能最大程度地保护人员、环境及设备安全。某天然气项目的高含硫生产气井中均安装有井下安全阀,其中的A井在进行开启井下安全阀作业时遇到无法打开的情况,通过实施细化的3套方案,最终成功打开了井下安全阀。

As a downhole tool to not only prevent blowout but also assure safety, subsurface safety valve is always installed at one position varying from 60 m to 200 m below wellhead, and its switch is controlled by ground hydraulic pressure. When ground facilities occurs abnormity, this valve may automatically switch off to avoid formation fluid uncontrollably flowing to the surface. As the last protective screen to stop accidents, it can also protect the staffs, the environment, and the facilities safety to the most degree. In a highsour gas project, all wells are equipped with subsurface safety valves; however, the valve in A well can not be opened when power on. This study presents three solutions to deal with this problem. In addition, some thinking to draw up these solutions and the key to solve the problem are summed up, all providing useful reference for solving problems occurred in subsurface safety valves with similar model.