Annular array energy transducer for pipeline axial residual stress detection based on critically refracted longitudinal wave method

The invention relates to an annular array energy transducer for pipeline axial residual stress detection based on a critically refracted longitudinal wave method. A critically refracted longitudinal wave method is utilized to realize axial residual stress detection of a circumferential array of an annular pipeline; and a plurality of organic glass wedges are uniformly assembled and distributed at an inner ring of a fixed flexible sleeve. When the annular array energy transducer works, the fixed flexible sleeve is wound the circumference of the annular pipeline and is fastened; and a certain pretightening force is added according to the radius of the pipeline. Besides, a plurality of pairs of piezoelectric transducers are assembled in each of the organic glass wedge, so that an axial mode of one sending and one receiving is formed, wherein the mode has a property of equipartition with 360 degrees; and moreover, a first critical angle is formed between each of the energy transducer and a contact tangent plane of each of the organic glass wedge. According to the invention, on-line detection on annular pipelines with different radiuses is realized; and the annular array energy transducer has characteristics of high sensitivity and convenience for using and the like; besides, the annular array energy transducer is especially suitable for detection on some large petroleum transmission pipelines.