Standard Practice for Acoustic Emission Monitoring During Continuous Welding

Importancia y uso:

4.1 Detection and location of AE sources in weldments during fabrication may provide information related to the integrity of the weld. Such information may be used to direct repair procedures on the weld or as a guide for application of other nondestructive evaluation (NDE) methods. A major attribute of applying AE for in-process monitoring of welds is the ability of the method to provide immediate real-time information on weld integrity. This feature makes the method useful to lower weld costs by repairing defects at the most convenient point in the production process. The AE activity from discontinuities in the weldment is stimulated by the thermal stresses from the welding process. The AE activity resulting from this stimulation is detected by AE sensors in the vicinity of the weldment, which convert the acoustic waves into electronic signals. The AE instrumentation processes signals and provides means for immediate display or indication of AE activity and for permanent recordings of the data.

4.2 Items to be considered in preparation and planning for monitoring should include but not be limited to the following:

4.2.1 Description of the system or object to be monitored or examined,

4.2.2 Extent of monitoring, that is, entire weld, cover passes only, and so forth,

4.2.3 Limitations or restrictions on the sensor mounting procedures, if applicable,

4.2.4 Performance parameters to be established and maintained during the AE system verification procedure (sensitivity, location accuracy, and so forth),

4.2.5 Maximum time interval between AE system verification checks,

4.2.6 Performance criteria for purchased equipment,

4.2.7 Requirements for permanent records of the AE response, if applicable,

4.2.8 Content and format of test report, if required, and

4.2.9 Operator qualification and certification, if required.

Subcomité:

E07.04

Volúmen:

03.03

Número ICS:

17.140.20 (Noise emitted by machines and equipment), 25.160.10 (Welding processes), 25.160.01 (Welding, brazing and soldering in general)

Palabras clave:

continuous welding; fusion solidification; heat-affected zone; high-temperature sensors; in-process defect location; thermal stress; wave guides ;