PSEUDORANDOM BINARY SEQUENCE APPARATUS AND METHOD FOR IN-LINE INSPECTION TOOL

• US 20100288049A1
• Filed: 08/07/2009
• Published: 11/18/2010
• Est. Priority Date: 08/08/2008
• Status: Active Grant

• Current Assignee: Pure Technologies Limited (Xylem, Inc.)
• Original Assignee: Pure Technologies Limited (Xylem, Inc.)
• Inventors: Hoyt, Philip M.
• Granted Patent: US 8,322,219 B2
• Time in Patent Office: Days
• US Class Current: 73/602
• CPC Class Codes: G01N 2291/2636 cylindrical from inside
• CPC Class Codes: G01N 27/82 for investigating the presence of flaws
• CPC Class Codes: G01N 29/043 in the interior, e.g. by shear waves

Abstract

An in-line inspection tool is disclosed for inspecting the wall of a pipeline while traveling therethrough. The in-line inspection tool may include a transmitter, a signal generator, one or more receivers, and a decoder. The signal generator may generate a pseudorandom signal, generate an inspection signal, and drive the transmitter with a convolution of the pseudorandom signal and the inspection signal. The transmitter may transmit the convoluted signal to the wall of the pipeline. One or more receivers may receive from the wall of the pipeline a received signal comprising at least one of the convoluted signal and a reflection of the convoluted signal. The decoder may identify the inspection signal within the received signal by cross correlating the received signal and the pseudorandom signal.

Claims

1. An in-line inspection tool for inspecting the wall of a pipeline while traveling through the pipeline, the in-line inspection tool comprising:

a transmitter;

a signal generator generating a pseudorandom signal, generating an inspection signal, and driving the transmitter with a convolution of the pseudorandom signal and the inspection signal;

the transmitter transmitting the convoluted signal to the wall of the pipeline;

one or more receivers receiving from the wall of the pipeline a received signal comprising at least one of the convoluted signal and a reflection of the convoluted signal; and

a decoder identifying the inspection signal within the received signal by cross correlating the received signal and the pseudorandom signal.

2. The in-line inspection tool of claim 1, wherein the transmitter and receiver each comprise one or more magnetostrictive electromagnetic acoustic transducers.

3. The in-line inspection tool of claim 1, wherein the transmitter and receiver each comprise one or more Lohrentz force electromagnetic acoustic transducers.

4. The in-line inspection tool of claim 1, wherein the transmitter and receiver each comprise an electromagnetic acoustic transducer.

5. The in-line inspection tool of claim 1, wherein the transmitter and receiver each comprise one or more piezoelectric ultrasonic transducers.

6. The in-line inspection tool of claim 5, wherein the one or more piezoelectric ultrasonic transducers operate at one of normal incidence and oblique incidence.

7. The in-line inspection tool of claim 5, wherein the one or more piezoelectric ultrasonic transducers operate as a phased array.

8. The in-line inspection tool of claim 1, wherein the transmitter and receiver each comprise one or more eddy current inspection devices.

9. The in-line inspection tool of claim 8, wherein the one or more eddy current inspection devices comprise one of pulsed eddy current devices and remote field eddy current devices.

10. The in-line inspection tool of claim 1, wherein the transmitter and receiver each comprise a magnetic flux leakage inspection device.