Abstract

A pragmatic and systematic technique has been developed to improve performance of the progressive cavity pumping system in a deep heavy oil reservoir where oil produces together with sand in an unconsolidated formation. More specifically, tapered thread has first been used to replace the conventional ones for strengthening the resistive torque of the entire string. The rotary anchor equipped with scalable slips is then adopted to not only avoid the tubing bend generally resulting from the compressed setting anchor, but also be easily retracted at the bottomhole even where sand is accumulated. A frequency converter is used to control the rotating speed, which allows the pump speed to be adjusted accordingly without powering off the motor. In addition, an upright notch intake is adopted to set below the orientation spool of the pump for mitigating sand accumulation. It has been found from over 200 wells that the newly developed technique can be used to greatly improve performance of the progressive cavity pumping system for increasing oil production from deep heavy oil reservoirs by significantly extending the life of the rod string. 

Key words: Progressive cavity pumping (PCP), deep heavy oil reservoir, performance improvement, tapered thread.