Calibrating electromagnetic corrosion detection tools via core saturation

Patent metadata

Field	Value
Publication number	US-2021198998-A1
Application number	US-201716077486-A
Country	US
Kind code	A1
Filing date	Jun 8, 2017
Priority date	Jun 8, 2017
Publication date	Jul 1, 2021
Grant date	—

Abstract

Methods and devices used to calibrate EM corrosion detection tools may estimate the effects of the presence of a core on measurements to enable more accurate corrosion detection in the well line. The methods may involve sending voltages to a core of a well tool disposed in the well line to obtain signals while the core is in a saturated and unsaturated state. Subsequent measurements using the core may be calibrated using a constant resulting from the division of the signals achieved at the core in the saturated and unsaturated states.

First claim

1 . A well line detection method comprising the steps of:
applying a first voltage at a core of a well tool disposed in the well line; logging at least one first signal using the well tool while the first voltage is applied to the core; removing the first voltage from the core of the well tool while the tool is disposed in the well line; logging at least one second signal using the well tool while the first voltage is removed from the core; and calibrating at least one measurement using both the first signal and the second signal.

2 . The well line detection method of claim 1 , wherein calibrating comprises taking a product of the at least one measurement and one or more of the at least one first signal divided by one or more of the at least one second signal.

3 . The well line detection method of claim 2 , wherein the first voltage is applied at DC frequency.

4 . The well line detection method according to claim 1 , further comprising the step of determining at least one of a defect, well line thickness, well line diameter, well line magnetic permeability, well line electrical properties, and well line metal content.

5 . The well line detection method of claim 4 , wherein the defect comprises corrosion in the well line.

6 . The well line detection method of claim 4 , wherein the calibrating step further comprises an average of a plurality of first signals.

7 . The well line detection method of claim 4 , wherein the calibrating step further comprises an average of a plurality of second signals.

8 . The well line detection method of claim 4 , wherein the at least one measurement using a product of an average of a plurality of first signals divided by an average of a plurality of second signals.

9 . The well line detection method of claim 4 , further comprising demagnetizing the core of the well tool.

10 . The well line detection method of claim 9 , wherein the demagnetizing step takes place after removal of the first voltage.

11 . The well line detection method of claim 4 , wherein the at least one measurement is made in the frequency domain.

12 . The well line detection method of claim 4 , wherein the at least one measurement is made in the time domain.

13 . An electromagnetic detection system for a well tool, comprising:
a saturable magnetic core; at least one transmitter coil disposed about the saturable magnetic core; and at least one receiver coil spaced apart a predefined distance from the at least one transmitter coil.

14 . The electromagnetic detection system for a well tool of claim 13 , further comprising a first power source coupled to the well tool and connected to saturate the saturable magnetic core.

15 . The electromagnetic detection system for a well tool of claim 14 , further comprising a second power source coupled to the well tool and connected to demagnetize the saturable magnetic core.

16 . The electromagnetic detection system for a well tool according to claim 13 , wherein the at least one transmitter coil and the at least one receiver coil are separate coils.

17 . The electromagnetic detection system for a well tool according to claim 13 , wherein the at least one transmitter coil circumscribes the at least one receiver coil.

18 . The electromagnetic detection system for a well tool according to claim 13 , wherein the at least one receiver coil is disposed about the saturable magnetic core.

19 . The electromagnetic detection system for a well tool according to claim 13 , further comprising a calibration coefficient stored in a computer-readable medium resulting from at least one measurement obtained using the well tool with the saturable magnetic core.

20 . The electromagnetic detection system for a well tool according to claim 13 , further comprising an amplified signal received using an unsaturated magnetic core.

21 . The electromagnetic detection system for a well tool of claim 20 , wherein the amplified signal is amplified by a factor of about 30 as compared to a signal received using a saturated magnetic core.

22 . The electromagnetic detection system for a well tool according to claim 13 , wherein the saturable magnetic core may be cylindrical in shape.

23 . The electromagnetic detection system for a well tool of claim 15 , wherein the saturable magnetic core is coupled in series to both the first power source and the second power source.

24 . A well tool having an electromagnetic detection system according to claim 13 , the well tool configured to log at least one first signal while a first voltage is applied to the saturable magnetic core and log at least one second signal while the first voltage is removed from the saturable magnetic core, wherein at least one measurement made by the well tool is calibrated using both the first signal and the second signal.

25 . The well tool of claim 24 , wherein the at least one measurement is calibrated by taking a product of the at least one measurement and one or more of the at least one first signal divided by one or more of the at least one second signal.

Assignees

• Halliburton Energy Services Inc

Inventors

• Donderici Burkay
• Fouda Ahmed E

Classifications

• G01N17/04

  Corrosion probes · CPC title

• G01V13/00 Primary

  Manufacturing, calibrating, cleaning, or repairing instruments or devices covered by groups G01V1/00 – G01V11/00 · CPC title

• G01N17/006 Primary

  of metals · CPC title

• G01N27/90

  using eddy currents · CPC title

• E21B47/006 Primary

  Detection of corrosion or deposition of substances · CPC title