Design method of curved-surface acoustic transmission wedge for circumferential ultrasonic detection of small-diameter pipe

Abstract

The invention discloses a design method of a curved-surface acoustic transmission wedge for circumferential ultrasonic detection of a small-diameter pipe. The design method comprises the following steps of: 1) determining parameters of an ultrasonic probe body corresponding to the curved-surface acoustic transmission wedge; 2) determining a combination mode of the curved-surface acoustic transmission wedge and the ultrasonic probe body; 3) determining the material of the curved-surface acoustic transmission wedge; 4) determining the curved surface radius of the curved-surface acoustic transmission wedge; 5) determining the position of a curved surface vertex of the curved-surface acoustic transmission wedge; 6) judging whether an ultrasonic sound beam generated by a square wafer in the ultrasonic probe body can be completely covered by the curved surface of the curved-surface acoustic transmission wedge or not; and 7) calculating the offset of the curved-surface sound transmission wedge relative to the ultrasonic incidence point of a plane sound transmission wedge. With the method adopted, the problems of poor coupling, difficulty in fixing a detection position and large man-made error during the detection of the small-diameter pipe by the plane sound transmission wedge can be effectively avoided; coupling conditions can be effectively improved; and line contact during detection is changed into surface contact, so that detection stability and defect positioning accuracy are improved.

Description

technical field [0001] The invention belongs to the field of non-destructive testing of thermal power plants, and in particular relates to a design method of a curved sound-transmitting wedge for circumferential ultrasonic testing of small-diameter tubes. Background technique [0002] Small-diameter tubes such as heating surface tubes for power plant boilers are made of steel ingots or solid tube billets through perforation to make capillary tubes, and then hot-rolled, cold-rolled or cold-drawn. In the production process, if the quality control is not good, the base metal of the small-diameter tube is generally prone to longitudinal linear defects. The existence of such defects will bring hidden dangers to the safe operation of the boiler. Cracks are easy to initiate and expand here, until the small-diameter tube on the heating surface The leak caused an unplanned outage. Longitudinal linear defects of small-diameter tubes can be detected by surface inspection methods such ...

AI Technical Summary

Problems solved by technology

[0004] The object of the present invention is to provide a method for designing a curved sound-transmitting wedge for circumferential ultrasonic detection of small-diameter pipes, which can effectively avoid poor coupling and difficulty in fixing the detection position when using a plane sound-transmitting wedge to detect small-diameter pipes , The problem of large human error, improve the coupling conditions, change the line contact to surface contact during detection, improve the stability of detection and the accuracy of defect location

Images