西二线管道腐蚀非开挖检测技术研究

针对埋地铁磁管道在非开挖条件下的腐蚀检测难题,对管道弱磁检测技术进行了工程应用验证.该技术利用弱磁检测仪对管道磁信号进行采集,通过分析磁信号曲线图波形特征,可以识别和定位腐蚀缺陷,同时可以根据腐蚀等级指标F值对腐蚀进行评价.首先根据磁信号dBx出现峰值并产生波动、dBy改变方向且过零点、同时dBz也出现峰值并产生波动的...

Research on trenchless corrosion detection technology for the second line pipeline of west-east gas transmission

Aiming at the problem of corrosion detection of buried ferromagnetic pipeline under trenchless condition, the application of weak magnetic detection technology is verified. This technology uses the weak magnetic detector to collect the magnetic signal of the pipeline. By analyzing the characteristics of the curve and waveform of the magnetic signal, it can identify and locate the corrosion defects, and evaluate the corrosion according to the F value of the corrosion grade index. Firstly, the locations of the corrosion defects are determined according to the characteristics of the magnetic signal on which there exist peak values and dB_x fluctuates violently at the peak values, dB_y changes direction and crosses zero point, and dB_z also has peak values and fluctuates violently. Then, Kp2131+941 and Kp2131+978 were selected as the reference points and sampling points respectively for corrosion defect damage grade evaluation, and the correction coefficient A is obtained through calculation. Finally, Kp2119+781 and Kp2128+762 are selected as excavation points for further verification, and the difference between the calculated F value and the real F value is within 2%. It is shown that the weak magnetic detection technology can be used to detect trenchless corrosion of buried ferromagnetic pipelines, and the corrosion defects can be accurately located according to the characteristics of magnetic signals. At the same time, the corrosion grade index F value can be used to evaluate the corrosion defects, and the results are accurate and reliable.