Application of Torsional Mode of Ultrasonic Guided Wave in Pressure Pipeline

Ultrasonic guided wave technology is presented as a new non-destructive pipeline inspection method for its rapid, long distance inspection and applied to special pipelines which are inaccessible by other conventional NDT methods. It can be widely used in the field of long range pipeline inspection. Dispersion and attenuation characteristics of torsional modes of ultrasonic guided wave in pipeline are presented. Propagation characteristics of T (0, 1) mode at different frequencies are studied. T (0, 1) mode excited by utilizing the magnetostrictive ultrasonic guided wave detection system is applied to detect the defects of pipeline. It can be concluded that the surface condition of the pipeline, the T (0, 1) mode excitation of different patterns and frequency have great effects on defect detection and the distance of guided wave propagation. Multiple factors should be considered to select the optimal frequency and excitation patterns as pipeline inspection in field.