QUANTIFICATION OF DEFECT SIZE FROM LONG RANGE GUIDED WAVE ULTRASONIC TESTS ON PIPES

The application of long range guided wave ultrasonic tests for pipes and pipelines has gained considerable support in recent years as a rapid screening tool for detection of corrosion and other degradation, particularly for inaccessible sections. However, its usefulness has been limited by the lack of detailed information about the dimensions of defects detected, which prevents an assessment of likely severity without additional testing or direct examination. This paper presents recent developments in determination of the size of defects arising from the use of focused ultrasonic energy from phased array transducers. The additional information obtained allows the pipeline operator to make at least initial assessments of defect severity without additional testing.