SHAFT PROXIMITY SENSORS

• US 20190326906A1
• Filed: 06/30/2016
• Published: 10/24/2019
• Est. Priority Date: 06/30/2016
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Camacho Cardenas, Alejandro, Johnson, Peter Benjamin, Steenson, Leo, Rendusara, Dudi Abdullah, Meredith, Andrew William
• Granted Patent: US 10,938,390 B2
• Time in Patent Office: Days
• CPC Class Codes: E21B 43/12 Methods or apparatus for controlling the flow of the obtained fluid to or in wells E21B43/25 takes precedence; valve arrangements E21B34/00
• CPC Class Codes: E21B 43/128 Adaptation of pump systems with down-hole electric drives
• CPC Class Codes: E21B 47/008 Monitoring of down-hole pump systems, e.g. for the detection of "pumped-off" conditions
• CPC Class Codes: F04B 17/03 driven by electric motors
• CPC Class Codes: F04B 47/06 having motor-pump units situated at great depth
• CPC Class Codes: F04D 15/0077 Safety measures F04D15/02 takes precedence
• CPC Class Codes: F04D 29/043 Shafts
• CPC Class Codes: F04D 29/086 especially adapted for liquid pumps
• CPC Class Codes: F04D 29/18 Rotors specially for elastic fluids F04D29/26
• CPC Class Codes: G01R 1/07 Non contact-making probes
• CPC Class Codes: G01R 19/2513 Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging
• CPC Class Codes: G01R 23/16 Spectrum analysis; Fourier analysis
• CPC Class Codes: G01R 23/165 using filters
• CPC Class Codes: G01R 23/20 Measurement of non-linear distortion
• CPC Class Codes: G01R 27/28 Measuring attenuation, gain, phase shift or derived characteristics of electric four pole networks, i.e. two-port networks; Measuring transient response in line transmission systems H04B3/46
• CPC Class Codes: G01R 27/32 in circuits having distributed constants , e.g. having very long conductors or involving high frequencies
• CPC Class Codes: G01R 31/2825 in household appliances or professional audio/video equipment testing LAN's H04L43/50; testing TV systems H04N17/00; testing loudspeakers H04R29/00
• CPC Class Codes: H03K 17/945 Proximity switches H03K17/96 takes precedence

Abstract

A system can include a housing that defines an interior space; a shaft disposed at least in part in the interior space of the housing where the shaft includes a longitudinal axis, a curved surface and an end surface; a submersible electric motor operatively coupled to the shaft where the submersible electric motor includes a cable connector; two proximity sensors where each of the proximity sensors includes a sensor aperture disposed in the interior space of the housing; and circuitry operatively coupled to the proximity sensors that determines position values of the shaft with respect to time based at least in part on output of the proximity sensors.

Claims

1. A system comprising:

a housing that defines an interior space wherein the housing comprises a longitudinal axis;

a shaft disposed at least in part in the interior space of the housing wherein the shaft comprises a longitudinal axis, a curved surface and an end surface;

a submersible electric motor operatively coupled to the shaft wherein the submersible electric motor comprises a cable connector;

two proximity sensors wherein each of the proximity sensors comprises a sensor aperture disposed in the interior space of the housing; and

circuitry operatively coupled to the proximity sensors that determines position values of the shaft with respect to time based at least in part on output of the proximity sensors.

2. The system of claim 1 wherein the circuitry is disposed in the interior space of the housing.

3. The system of claim 1 wherein the circuitry determines the position values based at least in part on curvature of the curved surface.

4. The system of claim 1 wherein the shaft comprises a wheel and wherein the curved surface corresponds to a surface of a rim of the wheel.

5. The system of claim 1 wherein the two proximity sensors are disposed in a transverse plane, directed toward an intersection point and separated by an arc distance.

6. The system of claim 1 wherein the sensor aperture is defined at least in part by a coil wherein the coil comprises a substantially circular coil or a substantially rectangular coil.

7. The system of claim 1 wherein the circuitry determines runout based at least in part on the position values.

8. The system of claim 1 wherein the circuitry determines an orbit of the longitudinal axis of the shaft based at least in part on the position values.

9. The system of claim 1 wherein the circuitry determines direction of rotation of the shaft based at least in part on the position values, rotation speed of the shaft based at least in part on the position values or direction of rotation and rotation speed of the shaft based at least in part on the position values.

10. The system of claim 1 wherein the circuitry determines an axial shift of the shaft based at least in part on the position values.

11. The system of claim 1 wherein the shaft comprises at least one target.

12. The system of claim 1 wherein the circuitry comprises frequency domain conversion circuitry.

13. The system of claim 1 wherein the circuitry is electrically coupled to the cable connector of the submersible electric motor for transmission of information from the circuitry to the cable connector.

14. The system of claim 1 comprising at least one redundant proximity sensor, at least one reference proximity sensor or at least one redundant proximity sensor and at least one reference proximity sensor.

15. A method comprising:

receiving parameter values for a shaft disposed at least in part in a housing and driven by a submersible electric motor wherein the parameter values are based at least in part on measurements acquired by proximity sensors disposed in the housing; and

determining an operational state of the system based at least in part on the parameter values.

16. The method of claim 15 wherein the parameter values comprise at least one member selected from a group consisting of runout values, orbit values, direction of rotation values, rotation speed values and axial shift values.

17. The method of claim 15 wherein the parameter values are based at least in part on a frequency domain conversion.

18. The method of claim 15 comprising two proximity sensors positioned at a known azimuthal separation to define an intersection point wherein the intersection point corresponds to a longitudinal axis of the shaft in a stationary state and wherein the parameter values correspond to distances between the intersection point and the longitudinal axis.

19. The method of claim 15 wherein the receiving comprises receiving the parameter values via a cable electrically coupled to the submersible electric motor.

20. A protector of an electric submersible pump system, the protector comprising:

a shaft that comprises a longitudinal axis;

a thrust bearing;

a runner;

a proximity sensor; and

circuitry that determines axial distance between a surface of the thrust bearing and a surface of the runner based at least in part on output of the proximity sensor.