Acoustic Emission: a Modern and Common NDT Method to Estimate Industrial Facilities

Gerald LACKNER, Gert SCHAURITSCH, Peter TSCHELIESNIG

TÜV Austria, Vienna, Austria

down time of industrial facilities, the desire for a practicable and economic NDT

method for periodic inspection becomes more and more interest. In the last few

years, the acoustic emission (AE) method achieved to fulfil this requirement. In

addition to the enormous development on hard- and software-components for AE

systems in the last years, the increase of practical experiences and knowledge leads

to a wide range of applications for this test method in Europe and worldwide. On the

other hand, the implementation of AE in the European standardisation assured a

high quality of certified test personnel. Parallel to this, the evolution of product and

process standards raised the acceptance of AE for industrial application. In many

European countries, for example in Austria, the AE is settled in the national law for

the periodic inspection of several types of storage and pressure vessels as well as

piping systems.

Amongst other, AE is able to detect and locate material defects, corrosion

and leakages with a high sensitivity and accuracy and enfolded usually the overall

shape of the tested structure. Due to this property, AE is particularly suitable as a

test method for large structures. In the practice, the verification of suspect places

detected by AE, will be done with other NDT methods (visual inspection, ultrasonic,

radiographic a.s.o.). Together with the interpretation of the AE results, an accurate

conclusion about the actual condition of the structure will be possible.

The presentation describes the current situation of AE from the Austrian

point of view and explains the interaction between different NDT methods based on

the results of some practical applications.