Ultrasonic Detection Of High Pressure Bend Crack

High pressure pipe sinks in the process of use need to withstand high impact pressure and alternating load, extremely easy to produce wall thickness reduction, fatigue crack and erosion pit and other defects, so the regular meeting of the tube is the important means to ensure the safety of high pressure pipe.This based on previous theoretical studies, focuses on the experimental study. First, the cause of the formation of the high pressure elbow crack is analyzed in detail, and the preventive measures are described in detail;In the third and fourth chapter, the classification, advantages and disadvantages, influencing factors and propagation path of ultrasonic in high pressure pipe were described, and the ultrasonic detection principle was analyzed. It was concluded that both digital ultrasonic detection and laser ultrasonic testing are based on acoustic wave propagation in the tube;Through field investigation, in the fifth chapter, this paper describes the method and the apparatus used in the field, and analyzes the two main crack defects of the detection of attention;In order to better detect the high pressure pipe flaw, in the sixth chapter, the experimental results were analyzed by using digital ultrasonic flaw detector and laser ultrasonic testing instrument. The test results were compared with the two experimental results. The detection accuracy of digital ultrasonic detector was higher, but the detection speed is slower.Therefore, the field detection, can use will two detection methods used in combination, formed a composite detection process, first to use laser ultrasonic visualization detector preliminary rapid detection, and some defects or possible defects of the work-piece using digital ultrasonic flaw detector for recheck again. It can not only improve the efficiency of detection, also can prevent undetected flaws.