Patent ID: 8746353
Filing Date: 2014-06-10
Classification: E21B,F04D

Abstract:
1. A method for detecting gas lock in an electric submersible pump assembly having an electric motor, a pump operationally coupled to the motor, and a string of discharge tubing extending from the pump to a surface, the method comprising: (a) providing at least one vibration sensor for detecting vibration of the electric submersible pump assembly; (b) operating the pump at a selected normal operation speed to pump well fluid up the well; (c) monitoring vibration of the electric submersible pump assembly for a predetermined period of time to create a vibration spectrum for the predetermined period of time; (d) comparing the vibration spectrum to a known vibration signature associated with a pump condition, wherein the pump condition precedes gas lock; and (e) in the event the vibration spectrum is substantially similar to the known vibration signature, determining that the pump is operating in a pre-gas lock condition.