Progressing Cavity Pumps (PCP) are used for artificial lift to minimize the flowing bottomhole pressure at the initial stage of cold, low-volume, high-sand-production wells in a heavy oil steamflood in the Sultanate of Oman. While both metallic and elastomeric stators have been installed in this field, the vast majority of the pumps are of the elastomeric variety.
In 2016, a study to improve the reliability and uptime of elastomeric PCP systems was conducted. This initiative included manufacturing visits, new bench test acceptance criteria, improved root cause failure analysis, updated training of personnel, and new pump selection and design criteria. Operational guidelines were also created and implemented with limitations on speed, torque, and pump intake pressure.
There were many lessons learned during the process that are shared in this paper. One lesson learned was that the legacy fit between the rotor and stator was creating unnecessary heat for the elastomer, thereby reducing its bottomhole temperature operational limit, which is extremely important in a steamflood.
By working collaboratively with the PCP provider to follow the new criteria and guidelines, the PCP failure rates have decreased by 41% and the pull rates for non-failure of the PCP systems decreased 57% by the end of Q1 2020. As a result, costs were reduced and well production uptime increased.
This paper provides details about this PCP improvement initiative and demonstrates how better practices and procedures with existing technology can lead to significant financial and production improvements. It also describes technology advancements being introduced to expand the elastomeric PCP operating envelope further for high-temperature applications.