Systems and Methods for Real-Time Monitoring of Downhole Pump Conditions

• US 20160102542A1
• Filed: 08/17/2015
• Published: 04/14/2016
• Est. Priority Date: 10/10/2014
• Status: Active Grant

• Current Assignee: Henry Research and Development LLC
• Original Assignee: Henry Research and Development LLC
• Inventors: DaCunha, Jeffrey J.
• Granted Patent: US 10,145,230 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: E21B 43/127 Adaptations of walking-beam pump systems
• CPC Class Codes: E21B 47/009 Monitoring of walking-beam pump systems
• CPC Class Codes: E21B 47/09 Locating or determining the position of objects in boreholes or wells , e.g. the position of an extending arm; Identifying the free or blocked portions of pipes
• CPC Class Codes: F04B 47/00 Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps by using positive or negative pressurised fluid medium acting directly on the liquid to be pumped F04F1/00
• CPC Class Codes: F04B 47/02 the driving mechanisms being situated at ground level F04B47/12 takes precedence
• CPC Class Codes: F04B 49/065 and making use of computers

Abstract

Systems and methods for improved monitoring of downhole pump conditions may provide real-time monitoring, high accuracy, and low noise when monitoring downhole pump conditions. Systems for monitoring pump conditions may be coupled to any suitable sucker rod pump, and may gather desired data from the pump. The desired data may be gathered at several points-in-time during a pump stroke to provide real-time monitoring. A wave equation corresponding to the behavior of the downhole pump may be solved when the desired data is received to provide real-time monitor. In some embodiments, the wave equation may be solved by separating it into static and dynamic solutions. In some embodiments, the dynamic solution of the wave equation may be solved utilizing an integral-based method.

Claims

1. A method for monitoring downhole pump conditions, the method comprising:

coupling a load sensor and a position sensor to a rod pump provided at a surface of a well;

gathering surface load data and position data from the load and position sensors of the rod pump;

calculating downhole load and downhole position utilizing a nonhomogenous viscous damped wave equation, wherein downhole load and downhole position is determined by solving a nonhomogeneous viscous damped wave equation utilizing an integral-based method;

plotting the downhole load and downhole position to provide a plot of the downhole position v. the downhole load.

2. The method of claim 1 further comprising:

separating a total solution ψ

(x, t) of the nonhomogenous viscous damped wave equation into a static solution σ

(x) and a dynamic solution γ

(x, t);

determining a static downhole position utilizing the static solution of the nonhomogenous viscous damped wave equation;

determining a static downhole load utilizing the static solution of the nonhomogenous viscous damped wave equation;

determining a dynamic downhole load and a dynamic downhole position utilizing the integral based method; and

wherein the downhole load is determined from the static downhole load and the dynamic downhole load, and the downhole position is determined from the static downhole position and the static downhole position.

3. The method of claim 2, wherein the integral-based method transforms a dynamic solution γ

(x, t) of the nonhomogenous viscous damped wave equation into a function of complex frequency.

4. The method of claim 2, wherein the dynamic solution γ

(x, t) of the nonhomogenous viscous damped wave equation is applicable to a non-periodic data set of the surface load data and position data.

5. The method of claim 1, wherein a rod of the rod pump has multiple tapers.

6. The method of claim 1, wherein the integral-based method determines the dynamic downhole position L at a time t from

7. The method of claim 1, wherein the downhole load and the downhole position data are calculated in real-time as the surface load data and position data is gathered, and the plot of the downhole position v. the downhole load is plotted in real-time.

8. A system for monitoring downhole pump conditions, the system comprising:

a rod pump providing a horsehead and sucker rod coupled to the horsehead, wherein the rod pump is position at a surface to pump fluids from a well;

a prime mover coupled to the rod pump, wherein the prime mover drives the horsehead;

a position sensor coupled to the rod pump at the surface, wherein the position sensor measures surface position data of the sucker rod;

a load sensor coupled to the rod pump at the surface, wherein the load sensor measures surface load data of the sucker rod;

a processor receiving the surface load and surface position data, wherein the processor determines downhole position and downhole load by solving a nonhomogeneous viscous damped wave equation utilizing an integral-based method; and

a display for plotting the downhole load and downhole position to provide a plot of the downhole position v. the downhole load.

9. The system of claim 8, wherein the processor:

separates a total solution ψ

(x, t) of the nonhomogenous viscous damped wave equation into a static solution σ

(x) and a dynamic solution γ

(x, t);

determines a static downhole position utilizing the static solution of the nonhomogenous viscous damped wave equation;

determines a static downhole load utilizing the static solution of the nonhomogenous viscous damped wave equation;

determines a dynamic downhole load and a dynamic downhole position utilizing the integral based method that determines downhole load and downhole position by solving the nonhomogeneous viscous damped wave equation; and

wherein the downhole load is determined from the static downhole load and the dynamic downhole load, and the downhole position is determined from the static downhole position and the static downhole position.

10. The system of claim 9, wherein the integral-based method transforms a dynamic solution ψ

(x, t) of the nonhomogenous viscous damped wave equation into a function of complex frequency.

11. The system of claim 9, wherein the dynamic solution γ

(x, t) of the nonhomogenous viscous damped wave equation is applicable to a non-periodic data set of the surface load data and position data.

12. The system of claim 8, wherein the sucker rod of the rod pump has multiple tapers.

13. The system of claim 8, wherein the integral-based method determines the dynamic downhole position L at a time t from

14. The system of claim 8, wherein the downhole load and the downhole position data are calculated in real-time as the surface load data and position data is gathered, and the plot of the downhole position v. the downhole load is plotted in real-time.