为防止井喷、保证油气井正常生产,设计了1种滑套式井下安全阀,对其结构、控制方式和工作原理进行了介绍;采用有限元的方法对井下安全阀由开启到关闭的动态过程进行模拟,在滑套阀不同倒角情况下,对滑套阀内部流场特性和所受压力的变化规律进行分析。分析结果表明,在滑套阀关闭过程中流体最大速度达到275 m/s,滑套阀所承受最大压力超过40 MPa;流体速度和滑套阀所受压力都随着滑套阀开度的减小而增大,随滑套阀倒角的增大而减小。此滑套式井下安全阀采用压力脉冲控制方式,液压管线只需要传递压力脉冲信号,杜绝了因管线泄漏而造成的井下安全阀失效。同时,驱动方式改为电机驱动,直接控制滑套式阀门的开合,反应迅速,提高了安全性和可靠性,具有较好的实用价值。
In order to prevent blowout and ensure the normal production of oil and gas wells,a sliding- sleeve subsurface safety valve was designed,and its structure,control method and working principle were introduced. The dynamic process of subsurface safety valve from open to close was simulated by using the finite element method,and the internal flow field characteristics and the bearing pressure variation laws of sliding- sleeve valve under different chamfer conditions were analyzed.The results showed that in the close process of sliding- sleeve valve,the maximum velocity of fluid reached 275 m / s,and the maximum pressure bearing by the sliding- sleeve valve exceeded 40 MPa. Both the velocity of fluid and the pressure bearing by the sliding- sleeve valve increased with the decreasing opening degree of sliding- sleeve valve,while decreased with the increasing chamfer of sliding- sleeve valve. The sliding- sleeve subsurface safety valve adopts the control method of pressure pulse,and the hydraulic pipelines only need to transfer the pressure pulse signals,which avoids the failure of subsurface safety valve caused by the pipeline leakage. Meanwhile,the driving mode changes to motor- driven type,which can directly control the open and close of sliding- sleeve valve,with rapid response,higher safety and reliability,and it has better practical value.