Study On Rim Defects Testing Of Immersed Phased Array Ultrasonic Technology

Water immersion phased array ultrasonic testing technique plays an important role in guaranteeing the operational safety. And how to improve and evaluate the verification of the testing has become one of the key issues that need be solved urgently. Water immersion phased array ultrasonic testing technique is an effective way to achieve wheel rim testing. It’s momentous to improve efficiency and ability of rim detection, and to make sure of the safety of trains’operation.This article mainly carried the work from three aspects, which are water immersion phased array ultrasonic testing technique theory, the sound field analysis and the flaw detection experiment reliability research.Firstly, this thesis has analyzed the state of art of water immersion phased array ultrasonic testing technique. Then introduced the application development of immersion ultrasonic phased array testing, and made a simple classification and description for wheel testing techniques in rail wheel. Besides, according to the theory and regularity of ultrasonic flaw detection technology, specially analyzed the development and application of ultrasonic in the railway sector. According to the principle of the water immersion phased array ultrasonic flaw detection, the use of flooding medium to ultrasonic testing has been analyzed, so a good understanding of the testing principle and methods of the immersion ultrasonic phased array detection has been got. Then a further analysis of the characteristics of immersion ultrasonic testing methods and a study on the structure of immersion ultrasonic probe and its impacts on the performance has been achieved. The method about how to determine the thickness of the water layer in immersion ultrasonic testing methods also has been described.Secondly, the simulation and characterize on sound field has been carried out, so that we can analysis their sound field distribution further on. During the simulation, four different kinds of probe had been used, which are basic straight probe, oblique probe and special surface probe, and ultrasonic phased array.Lastly, we focused on the results when we use immersion ultrasonic array probe. Then simulated and characterized sound field particularly. This thesis focuses on immersion ultrasonic phased array flaw testing technology in rim, and verifies this theory through a series of experiments, which include five important experiments. They are immersion ultrasonic phased array testing on laboratory rim, detection on the thickness of water layer, testing on the disturbance from flooding to rim flaw detection, keeping the probe to keep an angle to the surface of test piece in immersion phased array flaw detection. All the results of these experiments above have been analyzed, which verify the correctness of the principles and techniques used in this thesis. The results and analysis provide a technology Technical reference for flaw testing applications in railway.