Acoustic Emission Testing Benefits

Acoustic Emission

The basic concept of Acoustic Emission stimulation is to locate a yield point of the material where it can lead to a leakage or similar problems. Acoustic emission testing is normally practiced on welded piping and high energy steam piping in fossil power plants. The yield point causes a stress wave that propagates through the structure elastically. At some point it reaches the surface and stimulates a piezoelectric sensor. This sensor will convert mechanical energy into an electrical signal, amplified to be able to perform the analysis process.

Particularity of Acoustic Emission Testing

The inspection by acoustic emission differs from other non-destructive inspections on the following points:

1. The signal detected is generated by the same material
2. The evaluation is comprehensive and not limited by its geometry
3. Non-intrusive
4. The method is evaluating the response of the material to the application of effort; therefore, it is a dynamic technique

These factors provide the basic concept of Acoustic Emission to apply a pressure tank or other structures.

Advantages of Acoustic Emission Testing

Acoustic Emission inspection is applied in three ways to pressure vessels:

1. During the inspection phase of hydrostatic testing after being manufactured
2. When the equipment has been re-certified for an alternative use
3. Inspection when in service

Acoustic Emission can assess the structural integrity of a pressure vessel in production, under controlled conditions of operation and their behavior while in use. This information on how the recipient is working in service and where degradation is occurring when in operation can help define when and where other non-destructive inspections should be performed. Their use can increase the time between inspections or other alert to the presence of a potential weakness, for evaluation.

Acoustic Emission Findings

Acoustic emission testing will provide you with the following information depending on the method or recipient that you are testing.

1. Inspection of the entire structure - Determined carefully the area where the sensor is fixed, the inspection can be done with a small number of sensors. This ability of the acoustic emission application is quite attractive to large structures (sausages), spheres, heat exchangers where access and inspection areas are difficult and take too long.
2. Find 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 anomaly, but it is difficult to assess the effect when the structure is in service.
3. 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.
4. 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.