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Title: Non-contact feature detection using ultrasonic Lamb waves

Abstract

Apparatus and method for non-contact ultrasonic detection of features on or within the walls of hollow pipes are described. An air-coupled, high-power ultrasonic transducer for generating guided waves in the pipe wall, and a high-sensitivity, air-coupled transducer for detecting these waves, are disposed at a distance apart and at chosen angle with respect to the surface of the pipe, either inside of or outside of the pipe. Measurements may be made in reflection or transmission modes depending on the relative position of the transducers and the pipe. Data are taken by sweeping the frequency of the incident ultrasonic waves, using a tracking narrow-band filter to reduce detected noise, and transforming the frequency domain data into the time domain using fast Fourier transformation, if required.

Inventors:
 [1]
  1. Los Alamos, NM
Publication Date:
Research Org.:
Los Alamos National Security, LLC (Los Alamos, NM)
Sponsoring Org.:
USDOE
OSTI Identifier:
1019090
Patent Number(s):
7,963,165
Application Number:
US Patent Application 11/861,229
Assignee:
Los Alamos National Security, LLC (Los Alamos, NM) LANL
DOE Contract Number:
AC52-06NA25396
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION

Citation Formats

Sinha, Dipen N. Non-contact feature detection using ultrasonic Lamb waves. United States: N. p., 2011. Web.
Sinha, Dipen N. Non-contact feature detection using ultrasonic Lamb waves. United States.
Sinha, Dipen N. Tue . "Non-contact feature detection using ultrasonic Lamb waves". United States. doi:. https://www.osti.gov/servlets/purl/1019090.
@article{osti_1019090,
title = {Non-contact feature detection using ultrasonic Lamb waves},
author = {Sinha, Dipen N},
abstractNote = {Apparatus and method for non-contact ultrasonic detection of features on or within the walls of hollow pipes are described. An air-coupled, high-power ultrasonic transducer for generating guided waves in the pipe wall, and a high-sensitivity, air-coupled transducer for detecting these waves, are disposed at a distance apart and at chosen angle with respect to the surface of the pipe, either inside of or outside of the pipe. Measurements may be made in reflection or transmission modes depending on the relative position of the transducers and the pipe. Data are taken by sweeping the frequency of the incident ultrasonic waves, using a tracking narrow-band filter to reduce detected noise, and transforming the frequency domain data into the time domain using fast Fourier transformation, if required.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jun 28 00:00:00 EDT 2011},
month = {Tue Jun 28 00:00:00 EDT 2011}
}

Patent:

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