Method For Measuring Remote Field Eddy Current Thickness In Multiple Tubular Configuration

• US 20130193953A1
• Filed: 10/11/2011
• Published: 08/01/2013
• Est. Priority Date: 10/14/2010
• Status: Active Grant

• Current Assignee: Gregory Scott Yarbro, Jing Li, Michael Bittar
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Yarbro, Gregory Scott, Li, Jing, Bittar, Michael
• Granted Patent: US 9,310,338 B2
• Time in Patent Office: Days
• US Class Current: 324/76.77
• CPC Class Codes: E21B 47/085 using radiant means, e.g. acoustic, radioactive or electromagnetic
• CPC Class Codes: G01B 7/10 using magnetic means, e.g. by measuring change of reluctance
• CPC Class Codes: G01N 27/9066 by measuring the propagation time, or delaying the signals
• CPC Class Codes: G01N 33/20 Metals
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005

Abstract

In accordance with aspects of the present invention, a method of inspecting a well tubular is disclosed. The method utilizes a probe with a transmitter and detectors spaced from the transmitter by at least twice the diameter of the pipe to be tested. In some cases where multi-tubular structures are tested, the probe can include further detectors spaced from the transmitter by at least twice the diameter of the outer pipes as well. The phase of signals detected by the detectors relative to the transmitter are utilized to detect faults in the pipes.

Claims

1. A method of inspecting a pipe, comprising:

lowering a probe into the pipe, the probe including a transmitter and at least one detector separated from the transmitter by a separation distance equal to or greater than twice the diameter of the pipe;

providing a driving signal to the transmitter;

receiving detector signals from the one or more detectors;

determining the phase shift between the detector signals and the driving signal; and

determining faults along the pipe based on the phase shift.

2. The method of claim 1, further including monitoring the phase shift as a function of location in the pipe.

3. The method of claim 2, wherein determining a fault in the pipe based on the phase shift includes modeling a response of the probe to a fault.

4. The method of claim 3, wherein modeling a response includes providing a predicted response based on a fault length and dimensions of the probe.

5. The method of claim 1, further including determining a wall thickness of the pipe from the phase shift.

6. The method of claim 1, further including determining a wall thickness of the pipe and a second wall thickness of the second pipe, the second pipe being concentrically placed with the first pipe.

7. The method of claim 6, wherein determining the wall thickness of the pipe and the second wall thickness of the second pipe includes

determining the wall thickness of the pipe from the phase shift of the at least one detector;

measuring a second phase shift from at signals received by a at least one second detectors mounted on the probe, the at least one second detectors separated from the transmitter by a distance at least twice that of a diameter of the second pipe;

determining total wall thickness from the second phase shift; and

subtracting the wall thickness of the pipe to determine the second wall thickness.

8. The method of claim 1, wherein the probe further includes a magnetic field generator and the method further includes

generating a base log from the phase shift as a function of location in the pipe as the probe is lowered into the pipe;

and

generating a partial saturation log from the phase shift as a function of location in the pipe as the probe is raised in the pipe.

9. A method of determining thickness of a pipes in a multi-pipe configuration, comprising:

lowering a probe into the multi-pipe configuration, the probe including

a transmitter,

at least one first detector spaced from the transmitter by a distance greater than a first diameter of a first pipe of the multi-pipe configuration and less than a second diameter of a second pipe of the multi-pipe configuration, and

at least one second detector spaced from the transmitter by a distance greater than the second diameter;

measuring a first phase shift from the at least one first detector;

measuring a second phase shift from the at least one second detector;

determining a first wall thickness of the first pipe from the first phase shift;

determining a combined wall thickness from the second phase shift; and

determining a second wall thickness from the difference between the combined wall thickness and the first wall thickness.

10. A probe for testing a pipe, comprising

a transmitter;

and

one or more detectors separated from the transmitter by a distance at least twice that of the inner diameter of the pipe.

11. The probe of claim 10, further including one or more second detectors separated from the transmitter by a distance at least twice that of the inner diameter of a second pipe, the pipe and the second pipe being concentric pipes.

12. The probe of claim 10, further including a magnetic field generator separated from the transmitter and the detectors.

13. The probe of claim 11, wherein the magnetic field generator includes a permanent magnet.

14. The probe of claim 11, wherein the magnetic field generator includes a coil driving by a current.

15. A system for testing a pipe, comprising:

a controller; and

a probe coupled to the controller, the probe included a transmitter and one or more detectors separated from the transmitter by a distance at least twice that of the inner diameter of the pipe.

16. The system of claim 15, wherein the controller includes

a transmitter driver coupled to the transmitter;

a detection circuit coupled to the one or more detectors; and

a processor, the processor coupled to the transmitter driver and the detection circuit to determine the phase of signals received at the detectors relative to the signal provided by the transmitter driver.

17. The system of claim 16, further including an interface to a computer, the computer determining a fault based on the phase of signals received at the detectors and a model of a predicted response of the probe to the response.

18. The system of claim 15, wherein the probe includes first detectors spaced from the transmitter by a distance greater than twice the diameter of the pipe and second detectors spaced from the transmitter by a distance greater than twice the diameter of a second pipe that is positioned concentrically with the pipe.

19. The system of claim 18, wherein the processor determines a second phase shift from the second detectors.

20. The system of claim 19, wherein the processor further determines

a first wall thickness of a first wall thickness of the pipe from the first wall thickness, a combined wall thickness from the second phase shift, and determines a second wall thickness of the second pipe from a difference between the combined wall thickness and the first wall thickness.

21. The system of claim 16, wherein the controller further includes a cable controller coupled to the processor, the cable controller controlling the position of the probe in the pipe.