Mechanism to pump oil, water etc. from or in borehole - has delivery tube contg. pump-motor unit sealed and releasably coupled, unit wire-line retrievable and pref. non-return outlet valve

摘要

The pump mechanism is particularly intended for pumping a liquid from or within a (cased 3) borehole (2). It comprises a delivery tube (4; closed at its lowe end and provided with axial inlet slots at level below, a pump unit (21; 26,25 etc), screw pump with hydraulic drive motor below it), and means (63) sealing the pump unit in the tube (4). It further comprises means (64; 66,67,70) to releasably couple the unit with the tube into which it is lowered, and means (inward collar at upper end 104 or 64) for engagement by a wire-line grab.