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Dr. Channa Nageswaran, PAUT L3 and R&D Team Manager in the Non -Destructive Testing Integrity Management Group of TWI performed a webinar (available online on the TWI YouTube Channel).

Among others, some of the statements of this presentation mention that:

• Using simulation results to aid in inspection development must be approached cautiously
• Verification of key results by experiment should be a key component of such activity
• The CIVA platform is used extensively by TWI and has been validated for specific cases
• There is confidence in using the CIVA simulation platform for TRLs as TWI has undertaken some validation and published evidence

Watching it, you will be able to have an overview of Simulation vs. Experiment.

As concluded in the presentation, Modelling is a powerful tool to help in the development of techniques using these probes.

The EXTENDE team

Michele CARBONI and Andrea GIANNEO from Politecnico di Milano (Italy) presented at the 7th European-American Workshop on Reliability of NDE results from their work on the NDE of welded rails.

Comparison between experimental results and CIVA simulation are exposed.

Read or download the paper entitled " A reliability study of phased-array ultrasonic inspections applied to aluminothermic welds in rails"  here.

Abstract :

Nowadays,   long   welded   railway   rails   are   achieved   by   means   of aluminothermic and flush-butt welding processes. Compared to bolted joints, welds proved  to  be  effective  in  terms  of  reduced  wheel  damage,  ride  comfort  and maintenance.  However,  even  if  the  event  is  inexplicably  not  considered  in  relevant standards, surface cracks often initiate within the welded and the heat affected regions of  the  foot,  leading  to  brittle  failure.  On  the  subject,  a  recent  work  developed  a probabilistic methodology for determining day-by-day failure probability. However, apart from this structural integrity study and few others, a complete damage tolerance approach should also consider the capability of nondestructive inspections. The latter is  recognized  as  an  essential  input  to  define  maintenance  inspection  intervals.  The present  work  is  focused  on  the  capability  assessment  of  Phased  Array  ultrasonic inspection  applied  to  aluminothermic-welded  joints  by  means  of  Probability  of Detection curves, as a result of experimental and Model  Assisted data samples.

The EXTENDE team