Ultrasonic Imaging Detection of Welding Joint Defects of Pressure Pipeline Based on Phased Array Technology

As a new nondestructive testing technology, ultrasonic guided wave technology has the advantages of long detection distance, fast speed, low cost, and can detect places that can not be detected by general conventional detectors, such as special pipelines such as casing or buried pipelines. Pressure pipeline is an important special equipment. It is often necessary to carry out radiographic inspection of welded joints in regular inspection, but it is difficult to implement in some practical occasions. This paper studies the ultrasonic imaging testing of typical welding defects, and compares the ultrasonic imaging testing results with the radiographic testing results. The results show that ultrasonic imaging testing can not only detect all welding defects, but also has more advantages than radiographic testing in defect location and defect quantification. When radiographic testing is difficult to implement, ultrasonic imaging testing can be used as a supplement to radiographic testing. On the basis of understanding the research status and development trend of related technologies at home and abroad, and clarifying the principle and requirements of phased array ultrasonic imaging detection of steel pipes, the research on key technologies such as phased array ultrasonic imaging based on mechanical and electronic composite scanning and online phased array ultrasonic imaging detection of steel pipe near-end defects was focused on, which solved the problems of image splicing and blind spots of end defect detection in multi-scanning mode. At the same time, combining phased array ultrasonic nondestructive testing with mechatronics technology, a set of online quantitative nondestructive testing system for steel pipes based on phased array ultrasonic imaging was developed, and related experimental research was carried out to verify the feasibility and effectiveness of the proposed technology.