Brazil Deepwater BC-10 ESP Operation without Downhole ESP Gauges

Abstract

Abstract The paper reports on the integrated approach for the Brazil Deepwater BC-10 Electrical Submersible Pump (ESP) Operation without Downhole ESP gauges to safety operate the system and surveillance on light to heavy viscosity fluids and two phases, liquid – gas flow. The Electrical Submersible Pumping (ESP) system uses in Brazil are multistage centrifugal pumps for high rate and high boost applications inside a vessel system (caisson) powered with Pressure and Temperature gauges in each caisson, Venturi flowmeter at the discharge of the pump and a Motor POD located at the bottom of the motor that provides internal motor winding temperature (MWT), ESP vibration and Motor External Pressure for safety operation and to help predict ESP performance. To operate Brazil ESP systems without downhole gauges, an integrated analysis was performed to understand the more important and minimum acceptable variables required to operate the system, substitutions for the essential gauges and bypassed for non-critical gauges for ESP operations. Extended study and analysis were performed to cover in detail each of the alarms to allow running the ESP but maintaining the capacity to protect the system which will be the focus for this paper. All possible scenarios were considering and modelled for TRIP alarms such as out of range MWT, vibration, boost pressure, flow, pressure and temperature at the discharge to ensure capability functions for the critical variables were still available for the safety operation of the system. Low/High flow is a condition that may lead to ESP performance problems, in case of prolonged operation, a correlation from Gasmer Testing (1) based on ESP Boost and VFD current is proposed to calculate pump flowrate for safety operation to avoid ESP failures. The main technical contributions of this work are the detail approach, modeling and analysis for safety field operation without downhole gauges for predicting pump and motor performance. This study determines the minimum number of acceptance variables required and substitutions, as well variables that can be bypasses for non-critical gauges for ESP operations.