Can TOFD replace conventional UT on welding?

  • Can TOFD replace conventional UT on welding?

    Posted by george on 28/11/2021 at 5:58 pm

    Many advantages of the TOFD (Time of Flight Diffraction) method
    are reported in literature.
    Since the method works fast it can be an economically alternative to pulse echo UT or X-ray.
    What are the draw backs especially for welding testing?
    Is the method just a useful addition?
    Is there already a standard established?

    arsal replied 5 months, 3 weeks ago 2 Members · 1 Reply
  • 1 Reply
  • Welding

    arsal

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    28/11/2021 at 6:28 pm
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    It was explained a situation where TOFD is not ideal:
    “In a situation where a high-low (poor fitup or mismatch) exists between two welded pieces, the transmitted pulse forms two signals off the opposite wall, one from the
    higher side arriving prior to the one from the lower. The amount of high-low can be accurately assessed but if a defect occurred in the lower of the two sides the backwall
    signal from the higher side could obscure the defect.
    In both cases a pulse-echo technique can be adapted to
    inspect these areas to provide improved coverage where TOFD is not ideal”.