Acoustic emission

Acoustic emission is a class of phenomena whereby transient elastic waves are generated by the rapid release of energy from localized sources within a material.

Sound waves are commonly registered using piezoelectric sensors. Sensor output is amplified and transmitted by cable to the instrument, where the acoustic pulses are recorded and analyzed.

The acoustic emission technique allows detecting defects such as cracks, delamination, corrosion centers, areas of significant plastic deformation, etc. Knowing the speed of sound propagation in a material and recording the arrival time of sound pulse, we can determine the location of the defect.

Advantages of acoustic emission testing.

  • Inspection of the entire structure - This ability of the acoustic emission application is quite attractive to large structures , spheres, heat exchangers where access and inspection areas are difficult and take too long.
  • Finds significant flaws - if Acoustic Emission is used under actual loading conditions of the structure, it can distinguish abnormalities that are growing and others that are structurally insignificant. With other techniques, it is possible to establish the presence of an abnormality, but it is difficult to assess the effect when the structure is in service.
  • Structural severity measurement - Using the procedures of inspection and analysis of today, it is possible to give a measure of an active resource of a structure. The extent of the data is given with recommendations for follow-up inspections to be carried out periodically.
  • Non-intrusive, using Acoustic Emission sensors that are installed on the outside of the vessel wall. This does not require access into the vessel when the inspection is being performed. In insulated containers only one small manhole is needed for the installation of sensors and the rest of isolation remains unchanged.

The method is applied to the objects of oil and chemical industry for the control of pressure vessels and pipelines, in thermal and nuclear power generation, rail and air transport. The method allows detecting dangerous defects and corrosion damage, monitoring the quality of welded joints. Method is extended to monitoring building structures, overpasses and bridges made of steel and concrete.


RANIS AE equipment and software has many intricate features. We are ready to help you to master all the features for the success of your application. The training course includes the learning of practical skills of testing various objects in the industry.

We help our clients to conduct equipment verification at our premises.