Advertisement

The Effect of Equipment Bandwidth and Center Frequency Changes on Ultrasonic Inspection Reliability: Modeling and Experimentation Results

  • E. R. Green
Chapter
Part of the Review of Progress in Quantitative Nondestructive Evaluation book series

Abstract

The purpose of ultrasonic inservice inspection (UT/ISI) of nuclear reactor piping and pressure vessels is the reliable detection and sizing of material defects. Before defects can be sized, they must first be detected. This is typically done by analyzing ultrasonic echo waveforms with an amplitude greater than a certain percentage of that of a calibration reflector such as a 10% notch [1]. Studies performed at Pacific Northwest Laboratory (PNL) [2] and elsewhere [3–5] have shown that changing the components of an ultrasonic inspection system can greatly affect echo amplitude from a defect even when conventional calibration procedures are used, thus reducing the reliability of defect detection. To address this problem, ASME code [6] has provided tolerance levels for equipment parameters (e.g., center frequency and bandwidth) when inspection components are changed. However, some of the code requirements are based on engineering judgement and lack a strong analytical foundation. In this paper, the results of sensitivity studies performed to determine the effects of equipment parameter changes to provide an analytical basis for ASME code are presented.

Keywords

Center Frequency Inspection System System Bandwidth Pacific Northwest Laboratory ASME Code 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    ASME Section XI, Appendix III.Google Scholar
  2. 2.
    S. R. Doctor, et al., Integration of Nondestructive Examination (NDE) Reliability and Fracture Mechanics, NUREG/CR-4469, Vol. 1, pp. 6–17 (1986), avaitabte from GPO Sales Program Division of Technical Information and Document ontrol, U.S. Nuclear Regulatory Commission, Washington, D.C. 20 5.Google Scholar
  3. 3.
    E. Borloo, F. Lakestani, and F. Merli, PISC II - Parametric Study on the Effect of UT Equipment Characteristics (EEC) on Detection Loca-tion and Sizing, PISC III Report No. 10 - Final Report ( 1988j, available from Commission of the European Communities, Joint Research Center, Ispra, Italy.Google Scholar
  4. 4.
    D. E. MacDonald and S. M. Walker, Effects of Ultrasonic Equipment Variations on Crack Length Measurements, EPRI NP-5485 (1987), available from Research Reports Center, P.O. Box 50490, Palo Alto, CA 94305.Google Scholar
  5. 5.
    G. J. Posakony, Material Evaluation, 44, pp. 1567–1572 (1986).Google Scholar
  6. 6.
    ASME Code Case N-409, Revision 1.Google Scholar
  7. 7.
    E. R. Green and G. A. Mart, in Review of Progress in Quantitative Nondestructive Evaluation ( Plenum Press, New York, 1989 ), Vol. 8B, pp. 2259–2266.Google Scholar
  8. 8.
    C. B. Scruby, K. R. Jones, and L. Antoniazzi, Journal of Nondestructive Evaluation, Vol. 5, Nos. 3 /4, pp. 145–156 (1986).Google Scholar
  9. 9.
    G. F. Miller and H. Pursey. in Proceedings of the Royal Society, pp. 521–541 (1953).Google Scholar
  10. 10.
    G. J. Kuhn and A. Lutsch, The Journal of the Acoustical Society of America, Vol. 33, No. 7, pp. 949–954 (1961).MathSciNetCrossRefGoogle Scholar
  11. 11.
    J. Krautkramer and H. Krautkramer, Ultrasonic Testing of Materials, Third Edition ( Springer-Verlag, New York, 1983 ), pp. 605–606.CrossRefGoogle Scholar
  12. 12.
    K. F. Graff, Wave Motions in Elastic Solids (Ohio State University Press), pp. 311–343 (1975).Google Scholar
  13. 13.
    R. K. Chapman, Ultrasonic Scattering from Smooth Flat Cracks: An Elastodynamic Kirchhoff Diffraction Theory (Main Report), CEGB Report NWR/SSD/84/0059/R PWR/RCC/MWG/P(84)378 (1984).Google Scholar

Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • E. R. Green
    • 1
  1. 1.Pacific Northwest LaboratoryOperated by Battelle Memorial InstituteRichlandUSA

Personalised recommendations