Patent ID: 6725705
Filing Date: 2004-04-27
Classification: G01M

Abstract:
A method for locating gas leaks from underground gas pipelines comprising the steps of:positioning a first acoustic sensor having a first signal output in ground disposed one of substantially above said underground gas pipeline and at a distance from said underground gas pipeline; positioning at least one second acoustic sensor having a second signal output in said ground at a plurality of locations substantially above said underground gas pipeline; measuring a first output signal from said first acoustic sensor; measuring a second output signal from said second acoustic sensor at each of said locations; adaptively filtering said first output signal and said second output signal resulting in an adaptively filtered second output signal corresponding to each of said locations whereby signal components common to said first output signal and said second output signal are eliminated from said second output signal; determining a first rms voltage for said first output signal and a second rms voltage for each of said adaptively filtered second output signals; determining a difference between a statistical minima of said first rms voltage and each of said second rms voltages; and determining said location of said second acoustic sensor corresponding to a largest positive said difference, resulting in identification of said location closest to a gas leak from said underground gas pipeline.