To date some 1,500 Progressive Cavity Pumps (PCP) are utilized for artificial lifting of averagely 15.6 API0 crude oil with average viscosity of 500 cp at reservoir conditions, from the Staatsolie wells to the treatment facilities. The single lobe pumps are installed at an average depth of 1000 ft, producing from unconsolidated Tertiary sand reservoirs with rates varying from 10 up to 2000 barrels BFPD.

The shift from pumping jacks to PCP's was made in the mid 80's due to the flexibility and improved efficiency in drivehead configuration as well as volumetric efficiency of the PCP system contributing to significant reduction in lifting cost per barrel fluid. The PCP has established its robustness being in operations for almost 30 years under varying well conditions such as increasing water-cuts and fluid production rates, decreasing reservoir pressures, fluctuating GOR's and in vertical as well as in approximately 500 deviated wells.

Pump stator material, by default nitrile based, has been fabricated to suit the low aromatics content in the crude. Typical stator failures encountered include cracks and blistering combined sometimes by pitting and abrasion. The Mean Time Between Failure (MTBF) ranges from 2 months to almost 25 years.

In 2008, the Nodal Analysis concept was introduced to compare IPR and VLP for optimization purposes. VLP curves were created by modeling the PCP as two tubes, for which the inner tube would represent the annular flow between the pump helical rotor and stator and outer tube for the rod-tubing flow. An advancement that allowed the user to select the appropriate pump based on required pump differential pressure. CFER well modeling for pump seating, hydraulic torque, rod-tubing contact, rod string as well as rod–tubing loads were analyzed and optimized for given wellbore trajectory and doglegs.

The paper presents the versatility of the PCP application in different downhole environments, the performance and challenges to mitigate the common failures. Results of field cases and software simulations will be presented for best practice recommendations for progressive cavity pump applications in shallow heavy oil reservoirs.

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