Development Of Ultrasonic Thickness Gauge For Pipe Wall Corrosion

Nowadays,in the area of petrochemical industry,pipeline corrosion is a common problem,which will not only pose a threat to production safety,but also adversely affect the life and efficiency of equipment.Aiming to solve the problem above,ultrasonic thickness gauge is usually applied to measure the wall thickness of pipeline,so as to discover and evaluate the corrosion situation in time and help enterprises to prevent and maintain.At present,the thickness gauges used in petrochemical plants are expensive,inconvenient to carry,complicated to operate and inefficient in manual data processing.Therefore,the paper designs a hand-held thickness gauge with high cost performance,convenient to carry,simple to operate and wireless communication,and develops an offline data management software.The reliability and feasibility of the thickness gauge and software are verified by experiments on a prototype.The specific research schemes are as follows:(1)The overall scheme of thickness gauge and software is designed.Based on the analysis of the propagation characteristics of ultrasonic wave in the medium,the principles and characteristics of different ultrasonic detection methods are analyzed.According to the actual detection environment,the pulse reflection method is selected as the method to measure the thickness of the pipeline.According to the functional requirements and performance indicators of the thickness gauge,an ultrasonic transducer with small size and high precision and a hardware circuit schematic are proposed.Depending on the data management requirements,the corresponding offline data management software function module is devised.(2)An improved wavelet threshold denoising algorithm combined with envelope peak algorithm is proposed to achieve high-precision measurement of echo time difference.By analyzing the principle and characteristics of wavelet threshold and wavelet threshold function,the threshold is modified and the threshold function is improved to improve the signal-to-noise ratio of echo signal.The experimental results of three delay estimation methods are compared and analyzed.The envelope peak algorithm is chose to estimate the echo acoustic time difference and improve the measurement accuracy.(3)The experimental platform is built and the prototype is made to verify the effectiveness,stability and feasibility of the thickness gauge.Through many comparative experiments,the calculated sound velocity is calibrated and the best coupling agent is selected to further improve the detection accuracy.The effectiveness and stability of the thickness gauge are proved by comparing the measurement accuracy of the brand thickness gauge and different batches of prototypes.Through the sample measurement of the actual corroded pipeline,the feasibility of the thickness gauge has been proved.(4)A pipeline data management software is developed.Considering the functional requirements and engineering practice of the software,the software is designed according to the principle of modular design.The offline data management software is developed by combining the software function logic code written in Python language,Py Qt5 design software human-computer interaction interface and My SQL database to store measurement information data.Finally,the test results of the software show that the software realizes the functions of measurement data entry and query,equipment communication,data visualization and data export,and improves the work efficiency of the staff.