Research Of Detection Method Based On Ultrasonic For Pipeline Coating Peeling

The surface of industrial materials often cover anticorrosive coating, there are many detection methods for pipeline anticorrosion coating, electrochemical test method and frequency conversion-frequency choose method and other methods are commonly used. However, neither method could detect accurately whether the pipeline coating is peeling. As a new nondestructive detection technique, Ultrasonic detection technology has been widely used. The outer surface covering the corrosion layer or an insulation layer may mostly cause the attenuation of ultrasonic waves. Referring to this feature, this paper proposes the detecting the peeling of the steel anticorrosive coating by using the ultrasonic method.This paper researches on ultrasonic basic principle, production condition, propagation characteristics and detection method. With studying the propagation of ultrasonic in Two-layered Medium and obtain the wave equation of ultrasonic in Two-layered Medium. Researching theory and establishing the simulation model by ANSYS, the proposed force by applying a sinusoidal alternating ultrasonic method that has been applied in this paper. Establishment of different materials with different shapes corrosion layer on the steel plate, which is double-free plate model, simulation of ultrasonic wave propagation in these models, and visualization. Design of experimental system platform and experiment, the same material of the steel strip and the different materials of plexiglass are added to the steel plate as coating, and observe a signal waveform of the ultrasonic wave.Through the simulation of ultrasonic, ultrasonic propagation in various models with continuous reflection and refraction, and the mode will converse in dissemination of the waveform. Attenuation occurs, the shape of the coating affects the degree of attenuation of ultrasonic wave as propagation in a medium with a coating. The results show that double layer media with different materials affect spread and the same material affect the speed. This results validated the mode of propagation of the ultrasonic waves in the steel sheet, the coating with the same material affects the amplitude variation of the ultrasonic wave, with different material coating affects the propagation velocity of the ultrasonic wave. Similarly, the results show that ultrasonic could be used to detect the double-medium with different materials. In practical applications, the using of ultrasound for the detection of pipeline coatings, due to the anti-corrosion layer peeling, there will be significant changes in the the horizontal waveform and amplitude ultrasonic signal would be received, laid a fixed point of the pipeline coating and qualitative research foundation.