METHOD OF POSITIONING OF ANNULAR WELDING JOINTS OF UNDERGROUND STEEL PIPELINE Russian patent published in 2015 - IPC F17D5/00 

FIELD: metallurgy.

SUBSTANCE: method of positioning of annular welding joints of underground pipeline fabricated from ferromagnetic material comprises the measurement of induction of constant magnetic field above the pipeline axis with a certain step, plotting of the curve and finding of extrema of dependence of parameters of magnetic field induction from the linear coordinate, the measured values of parameters of induction are reduced to average value of the pipeline laying depth, the values of height of extrema, linear coordinates of extrema the height of which exceeds the pre-set threshold value are determined, the coordinates of annular welding joints of the pipeline are deemed as probable.

EFFECT: improvement of reliability of determination of linear coordinates of annular welding joints of the underground pipeline on the basis of results of land magnetometric measurements and possibility of searching of joints in automated mode.

2 cl, 10 dwg, 1 tbl