0
RESEARCH PAPERS

Flexural Torsional Guided Wave Mechanics and Focusing in Pipe

[+] Author and Article Information
Zongqi Sun

 GE Global Research Center KW-D259B, One Research Circle, Niskayuna, NY 12309

Li Zhang, Joseph L. Rose

Department of Engineering Science and Mechanics, The Pennsylvania State University, 212 Earth and Engineering Science Building, University Park, PA 16802

J. Pressure Vessel Technol 127(4), 471-478 (Feb 14, 2005) (8 pages) doi:10.1115/1.2065587 History: Received January 15, 2005; Revised February 14, 2005

Theoretical work on flexural torsional guided waves in pipe is presented along with angular profile experimental justification. Combined with previous work on flexural longitudinal modes and axisymmetric longitudinal and torsional modes, this work now forms a framework of nonaxisymmetric guided wave mechanics in pipe. Pipe inspection experiments are also carried out by flexural torsional wave focusing to demonstrate the advantages of the focusing technique.

FIGURES IN THIS ARTICLE
<>
Copyright © 2005 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Dispersion curves of 3 in. Schedule 40 steel pipe (OD: 88.9 mm, wall thickness: 5.49 mm) including all the propagating modes: axisymmetric and nonaxisymmetric (flexural) modes. FL: flexural longitudinal mode, FT: flexural torsional mode. First index: circumferential order, Second index: family order.

Grahic Jump Location
Figure 2

Guided wave categories. n: circumferential order (0, 1, 2, … ), M: family order (1, 2, 3, … ). The dashed line boxes represent mode groups formed by the guided wave modes with the same family order.

Grahic Jump Location
Figure 3

Schematic of pipe with a partial loading transducer on the OD. Transducer axial length: 2L.

Grahic Jump Location
Figure 4

Mode magnitude vs circumferential order of T(0,1)−FT(10,1) modes on a 3 in. Schedule 40 steel pipe at frequency 220 kHz with 45° circumferential loading length

Grahic Jump Location
Figure 5

Theoretical angular profiles of T(0,1)−FT(10,1) at 400 kHz, 45° partial loading on a 3 in. Schedule 40 steel pipe at axial distances (a) 0, (b) 0.5, (c) 1.0, (d) 1.5, (e) 2.0, (f) 2.5 m. The circumferential angles are relative to the transmitting transducer centered at 0°.

Grahic Jump Location
Figure 6

Experimental angular profiles (dotted lines) of T(0,1)−FT(10,1) at 220 kHz, 45° partial loading superposed with theoretical angular profiles (solid lines) on a 3 in. Schedule 40 steel pipe at axial distances (a) 0.25, (b) 1.1, (c) 1.5, (d) 2.2 m

Grahic Jump Location
Figure 12

Phased array focusing inspections with rotating the focal point around four quadrants in the circumference at the 6.096 m axial distance. It clearly shows the defect located in the first quadrant.

Grahic Jump Location
Figure 11

Comparison of three pulse-echo inspection results on a 16 in. Schedule 30 steel pipe with the T(0,1)−FT(10,1) group of modes

Grahic Jump Location
Figure 10

A 3.6% CSA saw cut notch on a 16 in. Schedule 30 steel pipe

Grahic Jump Location
Figure 9

A phased array transducer with 44 elements around a 16 in. Schedule 30 steel pipe circumference. The 44 elements are grouped into four quadrants with each covering 90°.

Grahic Jump Location
Figure 8

Time delay computation flow chart of the phased array focusing

Grahic Jump Location
Figure 7

Experimental angular profiles (dotted lines) of T(0,1)−FT(10,1) at 40 kHz, 85° partial loading superposed with theoretical angular profiles (solid lines) on a 16 in. Schedule 30 steel pipe (OD: 406.4 mm, wall thickness: 9.53 mm) at the axial distances (a) 1.1, (b) 3.2, (c) 4.1, (d) 5.5 m

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In