Method for producing from gas slugging reservoirs

Patent metadata

Field	Value
Publication number	US-2018371884-A1
Application number	US-201715632315-A
Country	US
Kind code	A1
Filing date	Jun 24, 2017
Priority date	Jun 24, 2017
Publication date	Dec 27, 2018
Grant date	—

Abstract

A method of operating a submersible pumping system includes the steps of placing the pumping system in a normal mode of operation and then detecting the possible presence of a gas slug in proximity to the pumping system by measuring a decrease in the load on the motor. Once the possibility of a gas slug has been detected, the method continues by placing the pumping system in a reduced speed cycle. The pumping system is kept in the reduced speed cycle until the absence of a gas slug in proximity to the pumping system is detected by evaluating two independent conditions within the pumping system.

First claim

What is claimed is:

1 . A method of operating a submersible pumping system that includes a pump driven by an electric motor, the method comprising the steps of:
placing the pumping system in a normal mode of operation; detecting the presence of a gas slug in proximity to the pumping system; reducing the speed of the motor; detecting the absence of a gas slug in proximity to the pumping system; and increasing the speed of the motor.

2 . The method of claim 1 , wherein the step of detecting the presence of a gas slug further comprises measuring a decrease in the load on the motor.

3 . The method of claim 2 , wherein the step of measuring a decrease in the load on the motor comprises measuring a decrease in the load on the motor over an established period.

4 . The method of claim 1 , wherein the step of detecting the presence of a gas slug comprises measuring a decreasing slope of a curve representing the pump intake pressure over time.

5 . The method of claim 1 , wherein the step of detecting the absence of a gas slug comprises measuring an increasing slope of a curve representing the pump intake pressure over time.

6 . The method of claim 1 , wherein the step of detecting the absence of a gas slug comprises measuring an increase in the pressure at the intake of the pump and an increasing slope of a curve representing the pump intake pressure over time.

7 . The method of claim 6 , wherein the step of detecting the absence of a gas slug further comprises:
increasing the speed of the motor; and measuring an increase in the load on the motor.

8 . The method of claim 7 , wherein the step of measuring an increase in the load on the motor occurs after the step of measuring an increase in the pressure at the intake of the pump.

9 . The method of claim 1 , wherein the step of detecting the absence of a gas slug comprises measuring an increase in the load on the motor.

10 . The method of claim 9 , wherein the step of measuring an increase in the load on the motor to detect the absence of a gas slug further comprises measuring an increase in the load on the motor without first detecting an increase in the pressure at the intake of the pump.

11 . A method of operating a submersible pumping system that includes a pump driven by an electric motor, the method comprising the steps of:
placing the pumping system in a normal mode of operation; detecting the presence of a gas slug in proximity to the pumping system; reducing the speed of the motor; detecting the absence of a gas slug in proximity to the pumping system, wherein the step of detecting the absence of a gas slug comprises:
measuring an increase in the slope of a curve representing the pump intake pressure over time; and
measuring an increase in the load on the motor; and
returning the pumping system to the normal mode of operation.

12 . The method of claim 11 , wherein the step of detecting the presence of a gas slug comprises measuring a decrease in the load on the motor.

13 . The method of claim 11 , wherein the step of detecting the presence of a gas slug comprises measuring a decreasing slope of a curve representing the pump intake pressure over time.

14 . The method of claim 11 , wherein the step of measuring an increase in the pressure at the intake of the pump further comprises measuring an increasing pressure above a threshold amount over a present period.

15 . The method of claim 11 , wherein the step of measuring an increase in the load on the motor occurs after the step of measuring an increase in the pressure at the intake of the pump.

16 . A method of operating a submersible pumping system that includes a pump driven by an electric motor, the method comprising the steps of:
placing the pumping system in a normal mode of operation; detecting the possible presence of a gas slug in proximity to the pumping system by measuring a decrease in the load on the motor; placing the pumping system in a reduced speed cycle; detecting the absence of a gas slug in proximity to the pumping system by evaluating two independent conditions within the pumping system; and returning the pumping system to the normal mode.

17 . The method of claim 16 , wherein the step of detecting the absence of a gas slug further comprises:
detecting an increase in the intake pressure of the pump; and detecting an increase in the load on the motor.

18 . The method of claim 17 , wherein the step of detecting an increase in the intake pressure of the pump further comprises waiting for an increase in the intake pressure of the pump for a first preset period of time.

19 . The method of claim 18 , wherein the step of detecting an increase in the load on the motor further comprises waiting for an increase in the load on the motor for a second preset period of time.

20 . The method of claim 18 , further comprising the steps of adjusting the first and second preset periods of time using a user interface within a motor control system.

Assignees

• Ge Oil & Gas Esp Inc

Inventors

• Collins Charles
• Wade Stacy
• Clark Darrel
• Rohlman Eric

Classifications

• E21B47/008

  Monitoring of down-hole pump systems, e.g. for the detection of "pumped-off" conditions · CPC title

• F04D15/0066

  by changing the speed, e.g. of the driving engine · CPC title

• F04D9/001

  Preventing vapour lock (F04D9/041 takes precedence) · CPC title

• F04D13/086

  the pump and drive motor are both submerged · CPC title

• F04D15/0209

  responsive to a condition of the working fluid (F04D15/029 takes precedence) · CPC title