| 摘要 |
<p>A downhole hydraulic pump for a well assembly includes an elongated production tubing (37). The hydraulic pump assembly (35) is attached to a bottom hole assembly (42), which comprises an upper assembly (48), middle assembly (71) with discharge ports (83), and a lower assembly (100) which contains a safety valve (102). The safety valve is opened by engagment with a pump extension (110) of 'free' jet pump (55).</p> |
