METHOD OF IN SITU DIAGNOSTICS OF LOCAL CORROSION FAILURE OF PIPE-LINES Russian patent published in 1999 - IPC

FIELD: environmental control, diagnostics of corrosion failure underground structures. SUBSTANCE: method is good for detection of both crack- like and stress-corrosion failure of pipe-lines. Samples of ground are taken. Suspensions of microorganisms are separated. Obtained suspension with dried mixture of mineral salt solution is incubated. Incubation lasts till color of indicator develops. Intensity of light absorption is measured. Index of coloring is determined. Statistic cluster analysis is performed with the help of method of basic components. Graph presenting spectrum of consumption of substrates is plotted and zones isolated in obtained graph are compared. Presence of corrosion failure of pipe-line, biological destruction of coat of pipe-line and biological degradation of contaminants in ground going on are evaluated by grouping in graph of symptoms of analyzed samples of ground. EFFECT: reduced volume of work and labor input thanks to conducting of diagnostics without opening of pipe-line. 3 dwg, 1 tbl