METHOD OF DIAGNOSING MAIN PIPELINES AND DEVICE FOR REALISING SAID METHOD Russian patent published in 2012 - IPC G01M3/24 F17D5/02 

FIELD: physics.

SUBSTANCE: outer surface of a pipeline, which is laid at the bottom, is probed with hydroacoustic signals. Concentration of methane in the gas cloud is determined using a methane sensor by measuring the value of change of the active layer of the methane sensor during diffusion of hydrocarbon molecules from sea water through a silicone membrane. The distribution law of the density of accumulation of gas bubbles on the depth is determined by distributing the range to layers with calculation of the density of accumulation of gas bubbles for each layer on the depth. Quantitative characteristics of rarefied gas accumulations are estimated. The number of receiving stations satisfies the condition for filling the investigated region along the pipeline route and transmission of information from the receiving stations to a control panel. At each receiving station, the measured ocean parameter values are converted to digital codes. A digital message is generated, which contains the number of the receiving station and the measured atmospheric and ocean parameter values in digital form. A high-frequency oscillation at carrier frequency is generated and then phase-shift keyed with the digital message and the formed phase-shift keyed composite signal is power amplified and broadcast. Each control station performs successive search and frequency conversion of signal. A phase-shift keyed composite signal at intermediate frequency is picked up and partially detected, as a result of which short heteropolar pulses are picked up, which correspond to time instances for abrupt change in phase of the phase-shift keyed composite signal. Said pulses are used to generate heteropolar voltage in direct and reverse code, which is proportional to the digital message. Said voltage is recorded and analysed, as a result of which the number of the receiving station and the value of ocean parameters is determined. Monitoring of the investigated region is performed at the control panel based on fund and/or archive information and picked up signals, with formation of a data base which contains information on the bottom topography, stationary and anomalous hydrodynamic processes, remote acoustic echosounding, with subsequent reconstruction of the topography of the medium, where emission and reception of signals is performed using a multifold reflection surveying procedure or identical probing. Fluctuation of anomalous signals on background levels of the natural medium is determined. Comparative analysis of stationary and dynamic processes is performed. Anomalous regions are identified. Developments are forecast by constructing parametric models of paired comparisons. If signals of new anomalous points appear during detection, the forecast is adjusted based on adaptive forecast evaluation techniques. Based on the forecast of development of anomalous processes in the investigated region, the extent of risks affecting safe use of the pipeline are determined through expert evaluations which are expressed by rankings. The matching of rankings is checked using Kendall and Spearman rank correlation coefficients, the Kendall and Babington-Smith rank concordance coefficient and a parametric Thurstone, Bradley-Terry-Luce model for paired comparisons, and nonparametric models of Lucian theory.

EFFECT: high safety of using offshore oil and gas terminals.

2 cl, 3 dwg