近间距平行管线的电磁场特征分析及应用

Analysis and application of electromagnetic field characteristics of close distance between parallel pipelines

针对近间距平行管线这一管网探测中的难题,尤其是管线定位的效果,首先整理推导了磁场水平分量的垂向梯度方程,然后正演计算了两根平行管线随间距变化的叠加磁场值:ΔH_x、H_x,讨论了曲线的特征及平面定位效果,得出ΔH_x的水平分辨率为1.4 h,反向电流管线H_x的水平分辨率为2.0 h,同向电流管线H_x的水平分辨率为2.4 h,ΔH_x水平分辨率最高。最后通过实际应用说明:在能直连或夹钳的情况下,直连法与夹钳法是管线探测的首选方法,然后可以考虑倾斜压线法或水平压线法。

Aimed at the difficult problem of close distance between parallel pipelines in the pipe network detection, especially the effect of line positioning, firstly, vertical gradient equations of horizontal component of magnetic field was deduced, and then, stacked magnetic field values between two parallel pipeline changed with distance were calculated： and Hx, discussing the characteristics of curve and the surface positioning effect, horizontal resolution of was 1.4 h, horizontal resolution of reverse current pipeline Hx was 2.0 h, horizontal resolution of synthetic current pipeline Hx was 2.4 h, horizontal resolution was highest. Finally, through the practical application showed that： direct method and clamp method was the first choice for pipeline detection method in the case of direct connection or clamp, and then oblique line pressing method or horizontal line pressing method was considered.