Remote field eddy current tools
AssigneeHalliburton Energy Services, Inc.
InventorsAhmed Elsayed Fouda, Burkay Donderici
Life of this patent
Estimating the term…
Abstract
Apparatus and methods to investigate a multiple nested conductive pipe structure can be implemented in a variety of applications. An electromagnetic pulsed tool disposed in the multiple nested conductive pipe structure in a wellbore can make a set of log measurements and provide a measured log at different depths in the multiple nested conductive pipe structure. The total thickness of the multiple nested conductive pipes can be determined at each depth in the measured log using a remote field eddy current look-up curve. The remote field eddy current look-up curve can be correlated to a remote field eddy current regime in time-domain associated with time decay response. Additional apparatus, systems, and methods are disclosed.
Claims20
A method comprising:
- forming a measured log including a set of log measurements at different depths using an electromagnetic pulsed tool disposed in multiple nested conductive pipes in a wellbore;
- generating one or more remote-field eddy current (RFEC) look-up curves based on measurements of normalized signal level responses for the multiple nested conductive pipes at one or more points in a time decay response;
- selecting an RFEC look-up curve at a point in the time decay response that indicates a total thickness of the multiple nested conductive pipes irrespective of a thickness for any specific one of the multiple nested conductive pipes;
- and
- determining the total thickness of the multiple nested conductive pipes at each depth in the measured log using the selected RFEC look-up curve.
A machine-readable storage device having instructions stored thereon, which, when executed by a control circuitry of a machine, cause the machine to perform operations, the instructions comprising instructions to:
- form a measured log including a set of log measurements at different depths using an electromagnetic pulsed tool disposed in multiple nested conductive pipes in a wellbore;
- generate one or more remote-field eddy current (RFEC) look-up curves based on measurements of normalized signal level responses for the multiple nested conductive pipes at one or more points in a time decay response;
- select an RFEC look-up curve at a point in the time decay response that indicates a total thickness of the multiple nested conductive pipes irrespective of a thickness for any specific one of the multiple nested conductive pipes;
- and
- determine the total thickness of the multiple nested conductive pipes at each depth in the measured log using the selected RFEC look-up curve.
A system comprising:
- a tool, the tool being an electromagnetic pulsed tool having a transmitter coil and a receiver coil arranged such the receiver coil receives a secondary field in response to a primary field generated from the transmitter coil;
- and
- a processor;
- a machine-readable storage medium comprising program code executable by the processor, the program code including instructions to,
- evaluate multiple nested conductive pipes in a wellbore at different depths from a set of log measurements acquired by use of the tool disposed in the multiple nested conductive pipes;
- form a measured log including one or more of the log measurements at the different depths in the multiple nested conductive pipes;
- generate a remote-field eddy current (RFEC) look-up curve based on measurements of normalized signal level responses for the multiple nested conductive pipes at one or more points in a time decay response;
- select an RFEC look-up curve at a point in the time decay response that indicates a total thickness of the multiple nested conductive pipes irrespective of a thickness for any specific one of the multiple nested conductive pipes;
- and
- determine the total thickness of the multiple nested conductive pipes at each depth in the measured log by use of the selected RFEC look-up curve.
Dependencies are inferred from the claim text.