This paper provides an overview of the qualification process of the highest power ESP ever installed into a hydrocarbon production system for artificial lift. The unit was selected and configured to interface with the existing deepwater offshore inflow and outflow systems without changes to the completion string or riser. The overall objective was to maximize the production capacity in terms of lift and flow rate given topsides power supply and running diameter constraints.
The initial requirement was to identify a suitable supplier that could provide a hardware solution with a high technical readiness level. The team first reviewed the hydraulic performance of the existing production systems and modeled the potential for improvement with the new equipment configuration given an expected efficiency and power factor for the proposed motor. The ESP equipment was configured with components that had multiple qualification and validation testing requirements. The motor and associated high voltage connector were key differences from the existing systems. The pump design was modified to accommodate projected operating ranges including additional stages for the necessary head requirements. The new subcomponents were subjected to application specific testing to qualify the designs for operating conditions with multiple technical assurance reviews conducted by the end user and supplier company technical discipline authorities. Full scale flow testing at a dedicated facility (Gasmer) for Caisson gas/liquid separator ESP systems, and component installation stackup tests for fit and interfaces were completed to validate the performance in multiphase flow and identify hardware changes needed for the completion design and the intervention procedures.
The qualification program was completed successfully, and a unit was deployed without incident, into a deepwater mudline caisson that has since been operated for live hydrocarbon production. The performance has met expectations and the unit efficiency and demonstrated capacity will allow for increased production. The use of a detailed qualification program that includes focused testing for individual system components and validation through full scale system integration testing ensures flawless deployment of technology improvements for critical well applications.
The system is the highest power ESP for hydrocarbon production. It includes a novel completion design to accommodate the effective running diameter for the motor. The use of a unique shroud design to stay within running diameter constraints allowed for minor modifications to the completion string design without system changes to the riser or caisson. This was both cost effective and reduced the time needed for development and manufacturing.