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Characterisation of Discontinuities with Advanced Ultrasonic Testing

Project Code: 33578

Link to Industrial Member Report


  • Assess the sizing capabilities of phased array ultrasonic testing (PAUT) and full matrix capture (FMC) using current characterisation and sizing methods from ISO 16827.
  • Compare the various sizing methods for both advanced ultrasonic testing (AUT) methods.
  • Develop best practice methods for characterisation and sizing of discontinuities for AUT applications.

Project Outline

The project will assess the current sizing capabilities of AUT applications with reference to ISO 16827:2012 (“Non-destructive testing — Ultrasonic testing — Characterization and sizing of discontinuities”) and investigate best practice for a variety of AUT techniques for sizing in butt-welded joints. The current methods for sizing with AUT are taken from manual ultrasonic testing (MUT) standards. During this project, these techniques adopted from ISO 16827:2012 will be reviewed and assessed to see how applicable they are for AUT techniques and whether different characterisation and sizing techniques may be more appropriate.

Probe manipulation for AUT is more rigid than for MUT. Standard AUT inspections involve the probe having a constant index offset from the weld; the probe moves along the length of the weld at a set rate. Flaw analysis in AUT is typically completed after inspection. The data collected during the inspection are recorded, allowing the operator to characterise and size indications later. The physical methods of collecting and analysing data for MUT and AUT, are different, but they currently still adopt the same techniques for characterising and sizing defects. An investigation into the characterisation and sizing capabilities and methods for AUT will develop new knowledge and expertise in the field for on-site sizing of defects in newly manufactured structures and ageing assets.

Trialling the variety of sizing methods (maximum amplitude, 6dB drop, 12dB drop, 20dB drop, etc) will provide a greater understanding to how these methods perform in different applications and inspections. Testing these methods on a range of sample thicknesses and defect types and sizes will build a far greater understanding of their capabilities and limitations.

Relevant Industry Sectors

Benefits to Industry

The assessment of the characterisation and sizing capabilities of AUT methods adopting the techniques from ISO 16827:2012 will allow a greater level of confidence in sizing defects for lab and site purposes. The work on defect critical sizing with PAUT and FMC will increase the level of confidence in sizing for new and ageing assets, and reduce the conservatism for defects for engineering critical assessment (ECA). New expertise and knowledge in the field of FMC will assist with development of upcoming standards on the method. 



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