Pipe inspection is generally executed with ultrasonic pulse echo testing where a small range of pipe wall under an ultrasonic transducer can be evaluated in one measurement. Costly and laborious point-by-point testing is required if a whole range of a pipe should be inspected. The author has investigated fast defect imaging for a plate-like structure using a scanning laser source (SLS) technique as an efficient defect inspection technique. Although the imaging technique is feasible in noncontact remote measurements, only a plate cross section under the laser irradiation surface can be evaluated. This study describes detection of wall thinning on the back of a pipe using resonance of guided wave propagating in a pipe circumference by noncontact remote measurements with the SLS technique. The narrowband elastic waves are generated in a pipe by modulating laser pulses with fiber laser equipment. When the modulation frequency is in harmony with the resonance frequency of a circumferential guided wave, the distribution of the frequency spectrum peak obtained with the SLS technique becomes identical to the resonance pattern of the circumferentially guided wave mode. The distributions are distorted for a pipe with wall thinning on the back indicating that this technique has a potential for detection of defects on the back of a pipe.

References

References
1.
Scruby
,
C. B.
, and
Drain
,
L. E.
,
1990
,
Laser Ultrasonics: Techniques and Applications
,
CRC Press
, Boca Raton, FL.
2.
Mckie
,
A. D. W.
, and
Addison
,
R. C.
,
1992
, “
Inspection of Components Having Complex Geometries Using Laser-Based Ultrasound
,”
Review of Progress in Quantitative Nondestructive Evaluation
, Thompson D.O., and Chimenti D.E., eds., Vol. 28, Springer, Boston, MA, pp.
577
584
.
3.
Blouin
,
A.
,
Levesque
,
D.
,
Neron
,
C.
,
Drolet
,
D.
, and
Monchalin
,
J. P.
,
1998
, “
Improved Resolution and Signal-to-Noise Ratio in Laser-Ultrasonics by SAFT Processing
,”
Opt. Express
,
2
(
13
), pp.
531
539
.
4.
Hayashi
,
T.
,
2016
, “
Imaging Defects in a Plate With Complex Geometries
,”
Appl. Phys. Lett.
,
108
(
8
), p.
81901
.
5.
Hayashi
,
T.
,
2017
, “
High-Speed Non-Contact Defect Imaging for a Plate-like Structure
,”
NDT E Int.
,
85
, pp.
53
62
.
6.
Hayashi
,
T.
, and
Ishihara
,
K.
,
2017
, “
Generation of Narrowband Elastic Waves With a Fiber Laser and Its Application to the Imaging of Defects in a Plate
,”
Ultrasonics
,
77
, pp.
47
53
.
7.
Kromine
,
A. K.
,
Fomitchov
,
P. A.
,
Krishnaswamy
,
S.
, and
Achenbach
,
J. D.
,
2000
, “
Laser Ultrasonic Detection of Surface Breaking Discontinuities: Scanning Laser Source Technique
,”
Mater. Eval.
,
58
, pp.
173
177
.
8.
Sohn
,
Y. H.
, and
Krishnaswamy
,
S.
,
2004
, “
Interaction of a Scanning Laser-Generated Ultrasonic Line Source With a Surface-Breaking Flaw
,”
J. Acoust. Soc. Am.
,
115
(
1
), pp.
172
181
.
9.
Sohn
,
Y.
, and
Krishnaswamy
,
S.
,
2006
, “
A near-Field Scanning Laser Source Technique and a Microcantilever Ultrasound Receiver for Detection of Surface-Breaking Defects
,”
Meas. Sci. Technol.
,
17
(
4
), pp.
809
818
.
10.
Takatsubo
,
J.
,
Wang
,
B.
,
Tsuda
,
H.
, and
Toyama
,
N.
,
2007
, “
Generation Laser Scanning Method for the Visualization of Ultrasounds Propagating on a 3-D Object With an Arbitrary Shape
,”
J. Solid Mech. Mater. Eng.
,
1
(
12
), pp.
1405
1411
.
11.
Dixon
,
S.
,
Cann
,
B.
,
Carroll
,
D. L.
,
Fan
,
Y.
, and
Edwards
,
R. S.
,
2008
, “
Non-Linear Enhancement of Laser Generated Ultrasonic Rayleigh Waves by Cracks
,”
Nondestruct. Test. Eval.
,
23
(
1
), pp.
25
34
.
12.
Clough
,
A. R.
, and
Edwards
,
R. S.
,
2014
, “
Scanning Laser Source Lamb Wave Enhancements for Defect Characterisation
,”
NDT E Int.
,
62
, pp.
99
105
.
13.
Clough
,
A. R.
, and
Edwards
,
R. S.
,
2015
, “
Characterisation of Hidden Defects Using the Near-Field Ultrasonic Enhancement of Lamb Waves
,”
Ultrasonics
,
59
, pp.
64
71
.
14.
Hayashi
,
T.
,
Murase
,
M.
, and
Salim
,
M. N.
,
2009
, “
Rapid Thickness Measurements Using Guided Waves From a Scanning Laser Source
,”
J. Acoust. Soc. Am.
,
126
(
3
), pp.
1101
1106
.
15.
Hayashi
,
T.
,
Murase
,
M.
, and
Kitayama
,
T.
,
2012
, “
Frequency Dependence of Images in Scanning Laser Source Technique for a Plate
,”
Ultrasonics
,
52
(
5
), pp.
636
42
.
16.
Salim
,
M. N.
,
Hayashi
,
T.
,
Murase
,
M.
,
Ito
,
T.
, and
Kamiya
,
S.
,
2012
, “
Fast Remaining Thickness Measurement Using a Laser Source Scanning Technique
,”
Mater. Trans.
,
53
(
4
), pp.
1
7
.
17.
Hayashi
,
T.
,
Murase
,
M.
,
Ogura
,
N.
, and
Kitayama
,
T.
,
2014
, “
Imaging Defects in a Plate With Full Non-Contact Scanning Laser Source Technique
,”
Mater. Trans.
,
55
(
7
), pp.
1045
1050
.
18.
Hayashi
,
T.
, and
Fukuyama
,
M.
,
2016
, “
Vibration Energy Analysis of a Plate for Defect Imaging With a Scanning Laser Source Technique
,”
J. Acoust. Soc. Am.
,
140
(
4
), pp.
2427
2436
.
19.
Hayashi
,
T.
,
2017
, “
Non-Contact Imaging of Pipe Thinning Using Elastic Guided Waves Generated and Detected by Lasers
,”
Int. J. Pressure Vessels Piping
,
153
, pp. 26–31.
20.
Hayashi
,
T.
,
Kawashima
,
K.
,
Sun
,
Z.
, and
Rose
,
J. L.
,
2003
, “
Analysis of Flexural Mode Focusing by a Semianalytical Finite Element Method
,”
J. Acoust. Soc. Am.
,
113
(
3
), pp.
1241
1248
.
21.
Hayashi
,
T.
,
Song
,
W.-J.
, and
Rose
,
J. L.
,
2003
, “
Guided Wave Dispersion Curves for a Bar With an Arbitrary Cross-Section, a Rod and Rail Example
,”
Ultrasonics
,
41
(
3
), pp.
175
183
.
22.
Hayashi
,
T.
,
Tamayama
,
C.
, and
Murase
,
M.
,
2006
, “
Wave Structure Analysis of Guided Waves in a Bar With an Arbitrary Cross-Section
,”
Ultrasonics
,
44
(
1
), pp.
17
24
.
23.
Hayashi
,
T.
, and
Murase
,
M.
,
2005
, “
Mode Extraction Technique for Guided Waves in a Pipe
,”
Nondestruct. Test. Eval.
,
20
(
1
), pp.
63
75
.
24.
Hayashi
,
T.
,
Nagao
,
M.
, and
Murase
,
M.
,
2008
, “
Defect Imaging With Guided Waves in a Long Pipe
,”
J. Solid Mech. Mater. Eng.
,
2
(
7
), pp.
888
899
.
25.
Nishino
,
H.
,
Asano
,
T.
,
Taniguchi
,
Y.
,
Yoshida
,
K.
,
Ogawa
,
H.
,
Takahashi
,
M.
, and
Ogura
,
Y.
,
2011
, “
Precise Measurement of Pipe Wall Thickness in Noncontact Manner Using a Circumferential Lamb Wave Generated and Detected by a Pair of Air-Coupled Transducers
,”
Jpn. J. Appl. Phys.
,
50
, p.
07HC10
.
You do not currently have access to this content.