Research On Eddy Current Sensor Ranging Technology In Eccentricity Detection Of Insulation Pipe

In order to improve the production quality of anti-corrosion insulation pipe,eccentric testing is required in the production process.In the eccentric detection,the eddy current sensor is used to detect the distance of pipeline.In the measurement process,the eddy current sensor probe parameters,pipe diameter,probe installation mode have influence on the distance detection.But there is no relevant standard to define its installation in eccentric detection process and the matching selection between probe diameter and pipe diameter.In order to solve these problems,based on the basic theory of eddy current sensor,the theory of non ax-symmetrical electromagnetic field and the principle of eccentric detection,the influence of the geometrical parameters of the probe on the performance of the eddy current sensor is calculated by MATLAB,and the parameters of the probe are selected under the guidance of different distance.At the same time,the eddy current sensor is used to analyze the three-dimensional non ax-symmetric eddy current field of pipeline measurement using ANSOFT MAXWELL,and the correctness of the model is verified according to the electromagnetic field analysis results,which can be used for subsequent study.Then using the finite element model,the influence of the radius of the pipe,probe radius,probe installation method and pipeline material on the distance detection is studied.The following problems are solved:1.How to choose the matching radius and the radius of the eddy current sensor;2.The eddy current sensor probe in the installation of the probe tilt and offset degree is defined,the probe offset distance is less than 6mm,tilt angle within 10 degrees can be ignored when the probe tilt and offset the influence of distance detection;3.Put forward the eccentric detection process of the probe installation mode and installation number,in order to eliminate the detection process of the test error.Finally,the eccentric detection experiment platform structure is designed independently and assembled.The influence curves of pipe diameter,probe offset and probe tilt on signal output are studied by experiments.The experimental results are consistent with the simulation results.Therefore,the results of this paper can provide technical guidance and theoretical reference for the practical application of eddy current sensor distance measurement in eccentricity detection.