| 摘要 |
<p>A subsurface solenoid well safety valve which is locked in the open position, after being opened mechanically, for preventing the valve from closing. A valve closure member is controlled by a tubular member which is mechanically moved downwardly to open the valve. An armature movable in the housing is actuated by a solenoid coil for locking the tubular member in the open position to the valve housing. Deenergization of the coil releases the armature and the lock and allows the tubular member to be biased to the open position.</p> |
