Research On Ultrasonic Wave On-line Monitoring System For Pipe Wall Thickness

The smooth operation of oil and gas pipelines is related to the safety of energy transportation.The research on on-line monitoring technology of oil and gas pipeline wall thickness based on ultrasonic technology plays an important role and significance in reducing the cost of human monitoring and improving the early warning ability of oil and gas pipeline thinning and failure.Based on the ultrasonic reflection method,this thesis designs a set of ultrasonic pipeline wall thickness on-line monitoring system,which has the high-precision monitoring ability of multi-channel oil and gas pipeline wall thickness.The research contents are as follows:(1)Finite element simulation of ultrasonic thickness measurement of pipeline.The finite element software is used to analyze the time and amplitude of ultrasonic propagation in the axial,circumferential and radial direction of the pipeline,and verify the feasibility of ultrasonic radial thickness measurement.Set different types and frequencies of ultrasonic pulse and wall thickness working conditions,simulate the ultrasonic echo thickness measurement process,obtain and analyze the thickness measurement results under various working conditions,and provide reference for the actual ultrasonic pulse setting.(2)Design of ultrasonic pipeline wall thickness on-line monitoring system.The ultrasonic pipeline wall thickness on-line monitoring system and its functional composition circuit,system control program,thickness measurement fixing device and data cloud reading interface are designed.The effectiveness of each function of the system is verified by circuit waveform test.(3)Experiment of ultrasonic pipeline wall thickness on-line monitoring system.The constant temperature ultrasonic thickness measurement experiment is carried out,and the system thickness measurement data and manual measurement data are used for linear regression fitting to obtain the system wall thickness correction equation.The variable temperature ultrasonic thickness measurement experiment is designed.Based on the ultrasonic thickness measurement data at different temperatures,the temperature correction ultrasonic thickness measurement fitting model is established to obtain the pipe wall thickness correction results under variable temperature conditions,so as to achieve the high-precision oil and gas pipeline wall thickness monitoring target in the design temperature range.