It is extremely difficult to produce heavy oil from a deep reservoir where oil produces together with sand in an unconsolidated formation. The traditional progressive cavity pump has found its limited reliability in such a deep reservoir due to a lower fluid level, which leads to a larger torque and heavier load as both the pump setting depth and forces imposed on the rod string are increased substantially. In this paper, a pragmatic efficient technique has been developed to improve reliability of the progressive cavity pump 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 as the collar is identified as the weakest point from both field applications and force analysis. 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 set at the bottomhole where sand is accumulated. In addition, a frequency converter is used to control the rotating speed, which allows the pump to be started and shut off smoothly. It has been found from over 200 wells that the newly developed technique can be used to greatly improve the reliability of the progressive cavity pump for increasing oil production from deep heavy oil reservoirs by significantly extending the life of the rod string.

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