ESP downhole equipment and their properties?
· Modular protector • It protects the motor from the well fluid • It provides pressure equalization between the motor and the wellbore • It carries the thrust load of the pump • It compensates motor oil volume during ESP system operation • It transfers torque from Motor to Intake devices and Pump · Electric submersible pumps Electric submersible pump is a part of downhole ESP system. It is installed between tubing and intake device such as Intake of Gas separator. Reservoir fluid is sucked by the pump through intake device, then it goes to blades of rotating impellers and due to that takes velocity and pressure. Cinetic energy of fluid is converted into its pressure when passing through diffuser flowpath of variable cross-section. · Priming (intake) devices • Intake • Gas separator • Multi-phase pump · Downhole motors Asynchronous motor (an electromechanical energy converter, operational principle is based on electromagnetic interaction between rotating magnetic field, created by three-phase current system, supplying from the net to stator winding, and currents, which appear in rotor winding when its conductors are crossed by rotating field.) Permanent magnet motor (In contrast with asynchronous motors, permanent magnet motors have rotor with permanent magnets and special scheme of supply voltage to the stator winding) · Downhole sensor system Provides data on pump / motor operating conditions • Prevents dangerous motor conditions e.g. well pumped off & attempt motor restart under backspin conditions due to unloading of fluid in string • Data triggers alarms - analysed at wellsite or main office • Provides continuous FBHP measurements – data transmitted to the surface via the power cable • Well test analysis after each pump shut down
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