Comparison of Phased Array Ultrasound to
Conventional Ultrasound and Radiographic Testing
for Bridge Welds
Publication: Publication Date: 1 January 2017Testing Method:
Phased array ultrasonic testing (PAUT) was
performed on nine complete joint penetration (CJP)
weld samples with internal and external weld
discontinuities to develop a discontinuity sizing
procedure using the backward tip diffraction
technique. The weld samples include flat plate CJP
welds, CJP T-joint welds, and a thickness transition
weld. The discontinuity sizing results were
compared to the physical size of the weld discontinuities
by sectioning the weld samples. It was
found that the response signal would vary greatly
depending on the scanning face and index offset.
Therefore, the combined results from first and
second leg scans from each available scanning
face were used to estimate the discontinuity size.
While the estimated discontinuity size was
typically quite close to the actual discontinuity
height and length for planar discontinuities, some
difficulties were encountered when there was
limited access for scanning, which caused the
discontinuity to be undersized. Oversizing was also
possible due to beam spread at long sound paths
or from misinterpretation of surface gouges.
Additional research is necessary to refine this
technique to determine the size of volumetric
discontinuities using PAUT. Additional testing was
performed using conventional ultrasonic testing
(UT) and radiographic testing (RT) to compare with
the PAUT results and the acceptability of each
sample under various acceptance criteria. It was
found that weld discontinuities that were
rejectable under combined conventional UT and RT
per AWS D1.5 may be acceptable under alternate
PAUT acceptance criteria. This typically occurred
when the weld discontinuity was volumetric in
nature such as internal porosity since UT is not as
effective at discerning the limits of volumetric
discontinuities compared with planar discontinuities.
The variation in acceptance criteria may also
be attributed to the fact that line scanning with
PAUT may not maximize the response amplitude
compared with raster scanning for conventional
- Armitt, T., and M. Moles, “Oscillating the Probe: Code Requirements and TOFD,” Materials Evaluation, Vol. 65, No. 11, 2007, pp. 1091–1098.
- ASME, ASME Code Case 2235-9: Use of Ultrasonic Examination in Lieu of Radiography, American Society of Mechanical Engineers, New York, New York, 2009.
- AWS, AASHTO/AWS, D1.5M/D1.5:2015 Bridge Welding Code, seventh edition, American Welding Society, Miami, Florida, 2015a.
- AWS, AWS D1.1/D1.1M:2015 Structural Welding Code – Steel, 23rd edition, American Welding Society, Miami, Florida, 2015b.
- BSI, BS 7910:2005 Guide to Methods for Assessing the Acceptability of Flaws in Metallic Structures, British Standards Institute, London, United Kingdom, 2005.
- EPRI, “Advanced Nuclear Technology: Reduction of American Society of Mechanical Engineers III Weld Fabrication Repairs—Fitness for Purpose,” Electric Power Research Institute, Palo Alto, California, November 2010.
- Ginzel, E.A., R. Thomson, and R.K. Ginzel, “A Qualification Process for Phased-Aarray UT using DNV RP-F118Guidelines,” NDT.net, 2011, pp. 1–12.
- McCracken, S.L., S.M. Swilley, Y. Sekinuma, O. Hedden, D. Cowfer, and S. Ranganath, “Proposed ASME Section III Code Case: Reduction of NDE Weld Repairs,” Proceedings of the ASME 2011 Pressure Vessels and Piping Conference, Vol. 1, 2011, pp. 949–959.
- Miki, C., K. Nishikawa, H. Shirahata, and M. Takahashi, “Performance Evaluation Test of the Time-of-flight Diffraction Technique for Welded Joints of Steel Bridges,” Journal of Testing and Evaluation, Vol. 36, No. 3, 2008, pp. 1–9.
- Moles, M., “Defect Sizing in Pipeline Welds – What Can We Really Achieve?” Proceedings of the ASME Pressure Vessels and Piping Conference, Vol. 484, 2004.
- Moles, M., and S. Labbé, “A Complete Solution for Weld Inspections: Phased Arrays and Diffraction Sizing,” Proceedings of the 2007 ASME Pressure Vessels and Piping Conference, 2007, pp. 595–600.
- Moles, M., L. Wesley, and T. Sinclair, “Accurate Defect Sizing using Phased Array and Signal Processing,” NDT.net, 2009.
- NAVSEA, “NAVSEA CWP-347: Alternative Process/Technology for Radiographic Testing of Pipe Welds,” United States Naval Sea Systems Command, Washington, D.C., 2011.
- Rana, M.D., O. Hedden, D. Cowfer, and R. Boyce, “Technical Basis for ASME Section VIII Code Case 2235 on Ultrasonic Examination of Welds in Lieu of Radiography,” Journal of Pressure Vessel Technology, Vol. 123, No. 3, 2001.
- Shenefelt, G.A., “Ultrasonic Testing Requirements of the AWS 1969 Building Code and Bridge Specifications,” Welding Journal, Vol. May 1971, pp. 342–349.
- Silk, M.G., “The Transfer of Ultrasonic Energy in the Diffraction Technique for Crack Sizing,” Ultrasonics, Vol. 17, No. 3, 1979, pp. 113–121.
- Washer, G., R. Connor, and D. Looten, “Performance Testing of Inspectors to Improve the Quality of Nondestructive Testing,” Transportation Research Record: Journal of the Transportation Research Board, Vol. 2408, December 2014, pp. 107–116.
- Wilkinson, S., and S.M. Duke, “Comparative Testing of Radiographic Testing, Ultrasonic Testing and Phased Array Advanced Ultrasonic Testing Non Destructive Testing Techniques in Accordance with the AWS D1.5 Bridge Welding Code,” Florida Department of Transportation, February 2014.
- Zippel, W.J., J.A. Pincheira, and G.A. Washer, “Crack Measurement in Steel Plates using TOFD Method,” Journal of Performance Constructed Facilities, Vol. 14, No. 2, 2000, pp. 75–82.
613 Page Views
0 PDF Downloads
1 Facebook Shares