Research On Pulse Double Remote Field Eddy Current Detection System Based On ARM

Ferromagnetic pipes are indispensable energy transportation tools in people's daily lives.These include oil and gas pipelines that transport oil and natural gas,as well as plumbing pipes that transport daily water and heating.These ferromagnetic pipes provide people with effective energy utilization.However,the wear and tear on the pipeline due to prolonged use.Timely detection of these pipeline wear and maintenance is of great security significance for energy transportation.This topic uses pulsed remote field eddy current detection technology to detect defects in small-diameter pipes under low-frequency excitation.It is found that the peak value of the induced voltage of the detection coil and the zero-crossing time point are too close,which reduces the detection resolution and makes it difficult to detect small diameter pipes.For this problem,an improved pulsed double remote field eddy current detection technique is proposed base on the original pulsed remote field eddy current detection technique.This technique solves the problem of difficult detection of small diameter pipelines under low frequency excitation.This topic firstly conducts theoretical analysis and mathematical model derivation of pulsed double remote field eddy current detection,and then uses the finite element simulation tool Maxwell to build and simulate the model.Through the preliminary analysis of the pipeline defects,the two-dimensional model is optimized.The feature quantity is extracted by systematic analysis of the full circumferential defects and fracture defects of the pipeline in the three-dimensional model.Through simulation research,it is found that when the pipeline is defective,the extremely high peak amplitude of the model output waveform is corresponding to the defect due to the change of the magnetic flux propagation path.Then,the reverse problem of the magnetic path of the pulsed double remote field eddy is found.When the depth or width of the defect is larger than a certain value,the direction and extent of the extremely high peak change are opposite to the previous one.This conclusion provides a new idea for the later research.The experimental system is built using STM32,including dual remote field probes,signal amplification circuits,power amplifier circuits,and ARM embedded acquisition systems.The system is used to detect the ferromagnetic pipeline with artificial defects.The experimental results show that the pulsed double remote field eddy current detection system has a good effect on the defect detection of small diameter pipelines under low frequency conditions,and also verifies the reverse problem of magnetic circuit,which provides a certain reference value for future pipeline eddy current testing.In this paper,a total of seventy-four pictures,nineteen tables and sixty references.