井下安全阀力学性能分析

井下安全阀对安全性和可靠性要求较高。以渤海油田常用油管携带式井下安全阀为分析对象,对其工作压力、地面控制压力、全开启和全关闭压力、最大下入深度和自平衡能力等关键力学性能进行分析。井下安全阀的工作压力值与地面液控压力值相等,其选取依据为井口压力; 全开启和全关闭液控压力值可通过压力曲线法得到; 最大下入深度取决于弹簧安装时的预紧力; 自平衡能力与活塞面积和自平衡孔面积的比值有关,比值越大,自平衡能力越强。

Mechanical Performance Analysis of Subsurface Safety Valve

Subsurface safety valve is strict with safety and reliability. Now by analyzing the subsurface safety valve which is carried with tubing, we can analyze the critical mechanical properties, such as working pressure, surface control pressure, full-open and full-shutdown pressures, maximum setting depth and the capability of self-balancing. The value of working pressure is equal to that of surface control pressure, which depends on the value of surface wellhead pressure. The value of full-open and full-shutdown pressure can be obtained by means of the method of pressure curve. The value of maximum setting depth depends on the value of preload force when spring is assembled. The value of self-balancing capability depends on the ratio of piston area and self-balancing hole area. The larger the ratio is, the stronger the ability of the self-balancing is.