Through-tubing, retrievable downhole pump system

摘要

A downhole pump system which allows the pump unit to be retrieved and re-installed through the production tubing while leaving the tubing, electrical cable, and the remainder of the components of the pump system in place. Preferably, the pump unit is run on a string of coiled-tubing through a lubricator which is positioned downhole in the production tubing. The pump unit includes a slip-joint at its upper end which (a) allows the length of the pump unit to be adjusted to compensate for the spacing between the seating surface and latching grooves in the nipple and (b) allows the pressures to be balanced across the pump unit during installation and retrieval.