Rod Store, Chevron U.S.A. Production Company
Many ESP failure modes result in the ingress of water into the motor resulting ultimately in motor electrical failure. Knowing that the isolation of the motor from well fluid has been compromised. Would allow the option of pulling the unit before electrical failure, significantly reducing the cost of repair. Various methods have been used to monitor insulation resistance to determine the electrical condition of the motor and cable, however, these methods are relatively expensive, and do not provide an indication until the insulation system has already been affected. This paper describes a method of detecting the presence of free water at the bottom of submersible motors. Fifteen such units are installed and functioning as expected, however, the benefit is yet to be demonstrated.