Permanent Magnet Motors/Powder Metallurgy Pump Stages: Increasing Profit Margins, Reserves, and Economic Limits through Efficient ESP Design
Authors: Lucas Jake , Donham Craig , Wrobel T. J. 
Published: October 2018

High volume, high water cut wells historically present a challenge in terms of economic production. Due to limitations with other forms of artificial lift, electrical submersible pumps are generally chosen for this type of application. Submersible pumps can move large volumes of fluid from great depths but are generally expensive to operate due to poor efficiencies. As electrical rates increase exponentially, permanent magnet motor (PMM) technology and powder metallurgy stage manufacturing can combat expense with high efficiency.

Through replacement of the industry standard asynchronous motor (AM) with the PMM, efficiencies have increased from 84% to 93% (Novomet. Permanent Magnet Motor. 2016). Over 10,000 PMMs operate worldwide. On top of PMMs, high-efficiency powder metallurgy centrifugal pumps are now manufactured and installed. The average pump efficiency between the flow ranges of 500 barrels of fluid per day (BFPD) and 12,000 BFPD is 72% as compared to an average of 64% over similar flow ranges with non-powder metallurgy pumps (Novomet. Power Save Systems. 2016).

In addition to power savings, operators are experiencing significant increases in equipment run time with PMMs and powder metallurgy pumps. By producing the required horsepower with reduced current loading, heat rise is reduced. The reduction of heat in electrical components increases run life. PMM systems are also much shorter in length to comparable systems. Less length means less components, higher reliability, and ease of access through high dog leg severities.

These advancements are made possible by the extensive testing that occurs at electrical submersible pump research and development centers. The data portrayed in this paper were derived from the Konnas testing facilities in Moscow, Russia, which is a throwback to the Soviet Era when the facility was used for research and development for electronic submersible pumps (ESP). For decades following the 1950's Konnas was responsible for 100% of the ESP pump designs in the former Soviet Union (Novomet, 2018). The test results were validated in over 1,000 wells across Russia, Egypt, Colombia, Argentina, Canada, Venezuela, and the United States. This paper provides an in-depth view of efficiency losses down to individual components; how these losses are mitigated; and how this technology affects the economics of a well.

This paper includes actual "before and after" well data from Tribal C-20 in the Wind River Basin of Wyoming. A PMM/powder metallurgy stage versus AM/cast stage system comparison of an actual well was economically analyzed to show the extension on the economic life of the well including the decrease in operating expense (OPEX) and the increase in reserves.

Many similar tests were recently conducted within this region and the average electrical savings equaled 30%. In this case, the power savings were on par with average savings of 27%. The electrical OPEX was decreased by $5,460.34 USD per month. From these savings the economical limit of the well increased; hence, the revenue, profit, and reserves increased along with the overall asset value.