RU2445594C1 - Method of diagnosing main pipelines and device for realising said method - Google Patents

Abstract

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

Description

The invention relates to the field of measurements, and more specifically to methods and devices for emergency diagnostics of high pressure pipelines, mainly laid along the bottom of reservoirs.

A known method for detecting leaks in a pipeline [patent RU No. 2108597], which is a method for laser location of metal leaks in industrial gas pipelines, which consists in scanning along a gas pipeline with three radio-frequency amplitude-modulated laser beams, the scanning frequency being coordinated with the modulation frequencies, carry out selective reception by the photodetector of the reflected laser signal transmitted through the methane cloud at three frequencies corresponding to the modulation frequencies of the laser beams, p When in use, the modulation frequency is matched to the frequency-time filter parameters photodetector. A device for implementing this method is a device for laser ranging methane leaks in industrial gas pipelines, which contains a laser emitter, a first amplitude modulator, a second laser emitter, a beam splitter, a second amplitude modulator, an optical system, a photodetector, a signal processing unit, a scanning device.

There is also a method of determining the place of leakage of liquid or gas from a pipeline located in the ground, which consists in reviewing the pipeline with a tracer, while scanning the pipeline with a television sensor, which determines the leak in which the pipeline is circled on a low-altitude aircraft using as a locator meter locator, and to determine the place of leakage, they additionally use a thermal imaging sensor, aligned with a thermal imaging sensor com, and carry out joint digital filtering of the signals of the locator, television and thermal imaging sensors [patent RU No. 2040783].

Known methods [patents RU No. 2108597, 2040783] have limited use, because their use is only possible to detect leaks in pipelines laid on the surface of the land or laid in the ground, and under favorable weather conditions for flights and the absence of navigational hazards.

Other known methods have similar disadvantages [USSR copyright certificate No. 1789899, patent RU No. 2017138]. The known method [USSR author's certificate No. 1789899] is a method for remotely determining the location of damage to the main pipeline by scanning the pipeline with a laser emitter, in which, when scanning for possible leaks, a command signal is generated to turn on devices for photographing in infrared and visible rays, with which make aerial photography in infrared rays of the pipeline route and aerial photography of the area, and determine the location of gas leaks t by overlaying snapshots of the route and terrain images. When superimposing track and terrain images, identification of registered objects is performed, as a rule, by expert estimates, which may introduce additional ambiguities in the research results.

In another known method [patent RU No. 2017138], which is a method for detecting natural gas leaks from pipelines and consists in irradiating a portion of the earth’s surface near the pipeline with laser radiation at two wavelengths, one of which λ ₁ enters the gas absorption band and the other λ ₂ lies outside it, recording the intensity of the radiation scattered by the surface at a wavelength of λ ₁ -P ₁ and λ ₂ -P _{2 the} formation of a video signal proportional to the ratio P ₂ / P ₁ , and comparing the video signal with an a priori specified threshold and in which m in order to increase the accuracy of determining the leak location and the accuracy of estimating the gas concentration in the leak cloud, the temperature contrast of the examined area is additionally recorded, which determines the coordinates of the probable leak location and its dimensions L on the surface, and the probable leak location is irradiated directly with laser radiation, and the average concentration of natural gas in the cloud leak is determined by the formula:

N = [2 (σ ₁ -σ ₂ ) Λ] ln ^-1 / (Р ₂ / P ₁ ), Λ = min {L / cosθ, Н), where σ ₁ is the gas absorption cross section at a wavelength of λ ₁ ; σ ₂ is the absorption cross section at a wavelength of λ ₂ , θ is the probing angle of the probable leak point, measured from the vertical; H - the height from which the survey is performed.

To clarify the leakage location, if more than one likely leakage point appears within the surveyed area, it is necessary to repeatedly irradiate the selected leakage spots with laser radiation at the same wavelengths from different directions with respect to the leakage cloud, which establish the true leakage point, which is essential increases the complexity of the method.

There is also a method for determining the coordinates of the location of the damage to the insulation of an underground pipeline by measuring the potential difference, in which the coordinates of the center of the defective places of insulation of the pipeline along the axis and the perimeter of its cross section in horizontal and vertical planes are determined by the maximum value of the potential difference in these coordinates by means of stepwise movement of the sensor along the pipeline axis perpendicular to the axis and the depth of the pipeline [patent RU No. 2076989].

This method, due to the possibility of stepwise movement of the sensor along the axis of the pipeline, perpendicular to the axis, and along the depth of the pipeline allows you to diagnose by the measurement results obtained by the step principle. However, this method has a positive effect in the control of local sections of the pipeline due to low productivity. Using it to control trunk pipelines having a length of 1000 km or more will require the use of a significant number of sensors, which will entail a significant increase in labor and material costs.

There is also a method for diagnosing pipelines with a large length, which is based on the method of acoustic emission [Site DIAPAC KORAL.htm].

The test procedure consists in changing the pressure level in the pipeline to stimulate the acoustic emission of sources associated with the presence of defects. The registration of the level of acoustic emission signals is carried out in real time, starting from the moment the pressure level changes by 5-10% of the working one in the direction of its increase or decrease. In this case, the location is made taking into account all real combinations of signals and the nature of their attenuation by filtering the noise, followed by automatic clustering and determining the characteristics of the clusters.

The application of this method allows for one cycle, comprising approximately 40-60 minutes, to cover 500 m of the pipeline. The disadvantages of the method is that it only controls the zone principle, with the sensors placed at a distance of up to 100 m. When performing a linear location, the probability of simultaneous operation of several sources of acoustic emission increases and, as a result, the determination of coordinates with large errors, and should also be access to the surface of the pipeline is ensured, which under operating conditions of pipelines located at the bottom of reservoirs cannot always be ensured due to the presence of bottom sediments. In addition, the zone location, with the placement of sensors at distances of more than 100 m from each other, leads to the ambiguity of the diagnostic results, since the location accuracy depends on the size of the base. As a result, obtaining the measurement results with the necessary accuracy is possible only by correlation processing of location signals, which should be adapted to solve the problem of location of transient type signals reflected in time to remove noise, including noise of electromagnetic origin.

There are also known methods for local monitoring of sections of underwater pipelines by visual inspection by divers or by television inspection from underwater vehicles [Prospect of the Marion plant, Leningrad, 1990], which, with relatively low productivity and efficiency, are labor-consuming and expensive operations and are practically not operational and objective control for long pipelines, as they can only be used under favorable hydrometeorological conditions ditions.

There is also known a method for measuring mechanical deformation in structural elements, which use a material that changes its phase under the action of deformation so that the measurement of the phase change shows the deformation. In this case, the material should be a transformed alloy steel with improved ductility. These elements can be made as elements attached to the surface of the structure, and to represent part of the structure [application for the grant of patent RU No. 93005061 from 03/18/93].

Since these elements can only be fixed on the pipeline by welding, this leads to the development of additional welding stresses and deformations, and taking into account the fact that plasticity depends on the deformation conditions (loading speed, temperature, pressure, etc.), when using this method for trunk pipelines laid at the bottom of reservoirs, it is necessary to take into account changes due to the influence of the external environment, which significantly reduces the effectiveness of this method.

There is also known a method of monitoring a pipeline by measuring in two sections and comparing with each other the level of ultrasonic vibrations generated by the transported medium, in which, in order to control the quality of manufacturing and installation of track connections of pipelines, the level of ultrasonic vibrations is measured behind the track connection in sections located at a distance less than one diameter and more than two diameters downstream [copyright certificate СССН No. 1227904]. This method has a positive effect when used to diagnose local pipelines laid on land, but is practically ineffective when placing pipelines along the bottom of reservoirs, especially at relatively large depths, when ultrasonic vibrations will be reflected from the reverberation layers.

The noted drawbacks are partially deprived of the method for emergency diagnostics of high pressure pipelines [patent RU No. 2079829], which consists in measuring the covariance function r _ij (f) of the dispersion δ _ij and the average value of the amplitude a _{j of} vibroacoustic noise in the initial period of the pipeline and through a given the operating time, and the condition of the product is judged by the result of a comparison of the measured values, in which measurements are made by several sensors located along the entire length of the pipeline, and all significant covariance functions are measured uu and bakterovskie logarithmic and functional, with comparisons functionals newly obtained with those obtained in stationary conditions during a sufficiently long time interval, and the presence of a defect is judged by the non-fulfillment of the following relationships:

;

;

;

;

;

;

;

;

;

;

where T is the duration of the measurement of the parameters of vibro-acoustic noise in stationary conditions;

Λ - bandwidth;

r _ij (t) is the signal received from the i-th sensor;

r _ij (t) is the estimate of the mutual covariance function in the initial period of observation;

r _ij (t) = cov (ξ _i (1 + s), ξ _i (s) - of the i-th and j-th signals;

a _i - stationary value of the average i-th signal

a _i = 1 / T ₀ ⌡ ^T ξ _i (t) dt;

d _i - logarithmic functional obtained in stationary conditions:

;

;

β _ij is the mutual Bacter functional of the i-th and j-th signals:

;

;

Λ is the scan interval;

;

;

;

- текущие значения тех же параметров.

;

;

;

- current values of the same parameters.

The main disadvantage of this method is that to compare the newly obtained functionals with those obtained under stationary conditions, a sufficiently large time interval is required, which does not allow using it for emergency diagnostics of high pressure pipelines.

In addition, to obtain a sufficient estimate, it is necessary to perform volumetric measurements for a set of statistical data with their subsequent processing using a complex mathematical apparatus (covariance functions, Bacter and logarithmic functionals), which, combined with the absence of conditions in the known method (as well as analogues) environmental influences caused by lithodynamic processes, bottom currents, waves and ice loads in the coastal zone, does not allow to quickly assess the degree of impact vii external factors. When diagnosing vibro-acoustic noise for pipelines located at the bottom of a reservoir, acoustic noise of the environment under extreme conditions introduces an additional measurement error, which significantly reduces the effectiveness of emergency diagnostics of high-pressure pipelines and narrows the scope of known methods, especially in areas subject to dynamic changes physical-geographical and hydrological factors.

Known methods of piping diagnostics provide a solution to problems aimed at identifying leaks of a transported product, or associated with the detection of defects of mechanical origin (dents, violation of the integrity of welded joints and insulation) caused by pitting and general corrosion on the pipe body and metal loss due to dents and scoring, mainly by measuring signals by vibro-acoustic noise or by changing the pressure using the zone principle. The use of known methods for emergency diagnostics of trunk pipelines laid along the bottom of reservoirs (seas and bays) and having a length of hundreds of kilometers is practically ineffective due to their low productivity.

For the diagnosis of long pipelines laid along the bottom of reservoirs, in addition to solving the problems of internal and external flaw detection in local areas, it is also necessary to solve the problem of identifying problem sections of the pipeline in the early stages of the pre-emergency situation simultaneously along the entire length of the pipeline, which can be achieved while ensuring continuous monitoring the technical condition of the pipeline with ensuring synchronization of the measured parameters along the entire length of the pipeline from a single real clock system th time and calendar. The need to solve this problem is due to the fact that the own dynamics of such pipelines is subject to a significant influence of external factors. Thus, elements of pipelines lying above faults or canyons of the seabed, under the influence of sea currents and the movement of sand waves, experience both stationary and pulsating loads of high intensity. These loads, in addition to the static deformations of the pipeline, cause their vibration, which during operation under extreme conditions can lead to fatigue stresses in the pipeline material in a relatively short time, and, as a consequence, to its premature failure. Low-frequency pulsations of the pressure of the pumped product affect the values of the cutting forces and bending moments that occur on bent sections of the pipeline. The arising loads depend on the geometry of the curved sections and the conditions for their fastening, and to a certain extent determine the resource of the curved sections. And if, using well-known methods for diagnosing local sections of the pipeline, including critical nodes and elements, it is possible to analyze the possible characteristics of the signals measured using sensors and then processing them according to statistical characteristics, such as power spectra and correlation functions, followed by comparison with reference values damage, then provide control of the technical condition along the entire length of the pipeline at the same time by known methods c is practically impossible due to the fact that the known diagnostic methods for a set of measured physical parameters do not allow to determine the degree of impact on the pipeline of time-varying factors such as an increase in static loads on the pipeline due to its deformation caused by horizontal-vertical movement of structures due to deepening into the soil of the seabed , the occurrence of free spans, the effect of marine sediments, due to the variability of the critical elements of the hydrometeorological factor such as ice cover, abrasion, including ice in the coastal zone, lithodynamic processes, surface waves in the coastal zone, underwater currents, sea level fluctuations, wind speed and direction in the coastal zone, air and sea water temperature in the coastal zone, the growth of marine deposits, the influence of inhibitors, the movement of sand waves.

To eliminate the noted drawbacks in the known method of emergency diagnostics of high pressure pipelines [application RU No. 2008120067/06 (023535) dated 05/20/2008], which consists in measuring physical quantities by several sensors located along the entire length of the pipeline, and the condition of the product is judged by comparison measured physical quantities obtained for stationary conditions during a certain time interval in which the measurement of physical quantities is carried out by means of sensors located inside the pipeline and with an external parties with synchronization of measured values from a single system of real-time clocks and a calendar, while using sensors located inside the pipeline, additionally measure the geographical coordinates; when establishing reference parameters, the physical parameters of the external environment are additionally determined with their subsequent correction when the environmental parameters change during the operation of the pipeline continuously and in cycles; n-sensors placed inside the pipeline are moved in the flow of the transported product; n-sensors move in the flow of the transported product at a speed equal to the flow velocity or less than the flow velocity; additionally determine the degree of impact on the pipeline of the external environment when changing its physical parameters by simultaneously measured signals by means of sensors placed inside the pipeline, and from the outside, the degree of impact is judged by comparing the measured and reference physical quantities by clustering and numerical simulation before and after exposure; the measurement of the physical parameters of the external environment is carried out by means of sensors located at observation points located at different levels in the horizontal and vertical planes of the external environment; n-sensors located at the observation points are stationary and on moving marine objects; n-sensors located at the observation points additionally record the signals of artificial acoustic anomalies in the aquatic environment and the acoustic impedance of the bottom layers.

In contrast to the known method for emergency diagnostics of high pressure pipelines [patent RU No. 2079829], in which the covariance function of the dispersion and the average value of the amplitude of vibroacoustic noise are measured in the initial period of the pipeline and after a given operating time, and the state of the product is judged by the result of a comparison of the measured values, in which measurements are made by several sensors located along the entire length of the pipeline, and all significant covariance functions, as well as Bacter and logarithmic, are measured functionals, and at the same time, the newly obtained functionals are compared with those obtained under stationary conditions for a sufficiently long time interval, and the presence of a defect is judged by the failure to fulfill a number of mathematical relationships in the technical solution [application RU No. 2008120067/06 (023535) from 05.20. 2008], using measuring sensors measure specific physical parameters, namely linear displacement, angular velocity, frequency and amplitude of vibration at the butt sections of pipelines, geographical coordinates, and a comparison of the results from measurements are performed taking into account corrective signals due to the influence of lithodynamic processes, bottom currents, waves and ice loads in the coastal zone, the measurement of physical quantities characterizing the state of the pipeline and the environment is performed with synchronization of the measured values from a single system of real-time clocks and a calendar, which is not requires a sufficiently large time interval for the collection of a reliable amount of statistical data with subsequent processing with the involvement of complex mathematical support This allows you to quickly diagnose the pipeline, and the input of correcting signals due to the influence of external factors expands the functionality of the method and eliminates subjective errors in the diagnosis, which is especially important for high-pressure pipelines laid along the bottom of reservoirs, including seas and oceans .

However, when detecting leaks of natural gas from pipelines, in addition to establishing the location of the leak, an important factor is the consideration of the movement of the gas cloud. Particularly important accounting for the movement of a gas cloud is in areas of offshore oil and gas terminals and in areas of heavy shipping. In unfavorable circumstances, for example, the appearance of a spark in the field of a gas cloud can lead to unforeseen consequences.

The objective of the proposed technical solution is to increase the operational safety of offshore oil and gas terminals.

This goal is achieved due to the fact that in the method for diagnosing pipelines laid at the bottom of reservoirs, the external surface of the pipeline is probed with hydroacoustic signals, the methane concentration in the gas cloud is determined by the methane sensor, by measuring the change in the active layer of the methane sensor during the diffusion of hydrocarbon molecules from sea water through a silicone membrane, determine the laws of the distribution of the density of the accumulation of gas bubbles in depth, by distributing the range on the layers with by collecting the density of the gas bubble accumulation for each layer in depth, the quantitative characteristics of rarefied gas accumulations are estimated, the number of receiving stations satisfies the condition of filling the studied area along the pipeline route, transmitting information from the receiving stations to the control panel, while the measured values at each receiving station parameters of the ocean are converted into digital codes, form a digital message containing the number of the receiving station and the measured values of the parameters of the atmosphere The signals of the ocean, in digital form, generate a high-frequency oscillation at the carrier frequency, manipulate it in phase with a digital message, and the generated complex signal with phase manipulation is amplified in power and emitted into the air, and at each control point, a sequential search and conversion of signals in frequency is performed, a complex signal with phase shift keying at an intermediate frequency, its frequency detection is carried out, as a result of which short unipolar pulses corresponding to the moments are emitted a jumplike change in the phase of a complex signal with phase shift keying, they generate a bipolar voltage in the forward and reverse code proportional to the digital message, register and analyze it, as a result of which the number of the receiving station and the values of the ocean parameters are determined, the monitoring area is monitored on the control panel using stock and / or archival information and recorded signals, with the formation of a database including information on the bottom topography, stationary and abnormal hydrodynamically x processes, remote sonar soundings, followed by restoration of the relief of the medium, while the radiation and reception of signals are performed according to the method of multiple overlapping or identical soundings, isolate fluctuations of anomalous signals at the background levels of the natural environment, perform a comparative analysis of stationary and dynamic processes, identify abnormal areas, Build a forecast for the development of the situation by constructing parametric models of pairwise comparisons; when new anomalous points appear during the registration process, the forecast is adjusted based on adaptive methods for predicting estimates; Based on the forecast of the development of abnormal processes in the field of research, the degree of risks affecting the safe operation of the pipeline is determined by the method of expert assessments expressed by rankings, and the consistency of the rankings is checked using the Kendall and Spearman rank correlation coefficients, the Kendall and Babington Smith rank concordance coefficients, and parametric models of paired comparisons - Thurstone, Bradley-Terry-Lews - and nonparametric models of the theory of Lucians, using a device property for implementing the method, which is a locator for viewing the pipeline, strain gauges and mechanical displacements installed on the surface of the pipeline and connected to the control panel, in which the locator for viewing the pipeline is made in the form of a sonar system, including an echo sounder, high-frequency and low-frequency side-scan sonar profilographs, satellite navigation system, an additional methane concentration sensor was introduced, moreover, a hydroacoustic system and yes snip methane-connected by a cable to the cable receiving station located on the water surface and juxtaposed with the stabilizing device designed as a submarine sail, and provided with satellite communication channel and a mover; the methane sensor and receiving-emitting devices of the hydroacoustic system (echo sounder antenna, side-scan sonar, pumping of parametric profilographs) are located in the outboard part of the receiving station, which is made in the form of an underwater probe.

The set of distinctive features of the claimed technical solution from the prior art has not been identified, which allows us to conclude that the claimed technical solution meets the patentability condition "inventive step".

The claimed technical solution is illustrated by the following drawings.

Figure 1. The implementation scheme of the method. The implementation scheme of the method includes a pipe 1 laid on the seabed 2, sensors for measuring vibro-acoustic noise and dynamic characteristics 3 of a pipe 1, a control panel 4 located at the sea terminal 5, a mid-orbit and low-orbit satellite constellation 6, a receiving station 7, an underwater probe 8, a cable cable 9, underwater sail 10 of the receiving station 7, antennas for satellite navigation communications 11 and 12, respectively, of the receiving station 7 and the control panel 4.

Figure 2. The block diagram of the measuring equipment of the receiving station 7 includes: a satellite communication channel 13, a network hub 14, a probe pulse generator 15, an echo signal receiver 16, sensors for measuring air temperature 17 and sea water 18, atmospheric 19 and hydrostatic 20 pressures, a flow meter 21, speed and wind directions 22, micro-computer 23 with software, spatial orientation unit 24.

Figure 3. The block diagram of the measuring equipment of the underwater probe 8 includes an antenna 25, an echo sounder 26, a side-scan sonar antenna 27, a pump antenna 29 of a parametric profiler 30, which is also an antenna of a high-frequency profiler 31, a low-frequency receive antenna 32 of a low-frequency parametric profiler 33, salinity sensor 34 , sea temperature sensor 35, flow sensor 36, hydrostatic pressure sensor 37, geophone 38, methane sensor 39, controller 40.

The essence of the proposed technical solution is as follows.

Sensors 3 are installed along the length of the high-pressure main pipeline at the butt sections, which are, for example, an accelerometer that provides a measurement of a wider range of physical parameters compared to a gyroscope and a centripetal force meter, which allow measuring only the angular velocity of a solid, which is one of the quantities characterizing his physical condition.

Sensors (accelerometers) are mounted on the pipeline by means of retaining rings and are connected to the control panel 4 of the marine terminal 5 by an optical fiber cable.

Using sensors 3 measure the following parameters:

- linear displacement;

- angular velocity;

- frequency of vibration;

- amplitude of vibration.

Diagnostics of the pipeline is performed in the following sequence.

By means of sensors with a sensitive element, which is an inertial information converter [patent RU No. 2076989], parameters are measured at the butt sections of the pipeline for certain time intervals.

On the fiber-optic cable, the measured parameters are transmitted to the module a posteriori processing of the measured physical quantities, located on the control panel 4.

Simultaneously with these measurements, similar physical parameters are recorded by means of sensors located inside the pipeline, mainly at the points where the valves are concentrated (compressor stations, temperature compensators, detachable elements, etc.), which are also transmitted to the coast station via fiber-optic cable. Using sensors moving with a speed or less than the flow rate of the transported product, measure the geographical coordinates of the pipeline, as well as the radii and bending angles of pipe sections, the inner diameter of the pipeline. The sensors are a torpedo-shaped body made of high-pressure polymer material, equipped with a propulsion device made in the form of several polyurethane cuffs or in the form of a plate-type rotor [patent RU No. 213209], as well as supporting and odometric wheels. A strap-down inertial navigation system, a central controller and memory unit, an odometric unit, a transverse seam identification unit, a motion control module for defectoscopic measurements, a power supply are installed on the inner surface of the housing. A module for profilometric measurements, a module for magnetic flaw detection, and acoustic emitters are installed on the outer surface of the housing. The central controller and memory unit via a telephone communication line is connected to the a posteriori processing module of the measured physical quantities located on the control panel 4 of the marine terminal 5.

Separate sensors moving in the flow of the transported product have a lower speed than the flow rate, which is necessary for recording physical quantities characterizing the defects caused by pitting and general corrosion on the inner surface of the pipeline with the determination of the spatial position of these defects. The spatial position of moving sensors is determined by a strapdown inertial navigation system, which provides the generation of parameters such as coordinates, speed, course, angular velocities and accelerations in the horizontal and vertical planes relative to the axis of the pipeline, linear accelerations.

When establishing reference parameters, the physical parameters of the external environment are additionally determined with their subsequent correction when the environmental parameters change during the operation of the pipeline continuously and in cycles.

To implement this task, sensors are used to measure the temperature of water 18 and 35, air 17, atmospheric pressure 19, hydrostatic pressure 20 and 37, flow meters 21 and 36, salinity 34, wind speed and direction 22.

The spatial orientation unit 24 includes tilt and azimuth meters; accelerometer unit for measuring wave field components; synchronization unit; Power Supply.

By means of a geophone 38, sound frequencies caused by the noise of the marine environment with spectral characteristics being separated are filtered, which are then filtered by dividing the spectrum into non-intersecting intervals using a discrete wavelet transform [Astafieva N.M. Wavelet Analysis: Fundamentals of the Theory and Application Examples. Physics-Uspekhi. 1998, vol. 166, No. 11, pp. 1145-1170] by transmitting signals through wide-band and narrow-band filters, which ultimately eliminates signals due to sea noise in the frequency range of 1-10 Hz [Ilyichev V. AND. Investigation of the acoustic noise field of the ocean by vector-phase methods // Acoustics of the ocean environment / Ed. L.M. Brekhovskikh. - M .: Nauka, 1989. - p.140-152].

Measurements by means of sensors in one or another combination are performed with synchronization of the measured values from a single system of real-time clocks and a calendar.

The physical quantities measured by sensors installed directly on the pipeline characterizing the technical and operational state of the pipeline and the external environment via communication lines are sent to the a posteriori processing module of the measured physical quantities of the control panel 4 of the marine terminal 5, where, according to the results of comparing the standard and measured physical quantities by sensors perform pipeline diagnostics and the degree of impact on the pipeline environment when changing its physical parameters after COROLLARY clustering and numerical simulation grid by nonlinear methods of numerical analysis.

By means of measuring equipment of an underwater probe 8, including hydroacoustic means as part of a panoramic echo sounder 26 having two directivity characteristics, a side-scan sonar 28 with a switched directivity characteristic, parametric profilographs 31 and 32 detect and identify artificial acoustic anomalies in the aquatic environment by measuring the speed of sound , density and acoustic impedance in the depth range from 0.5 to 250 m (the design range for the occurrence of pipelines is provided as part of the Nord Stream (Baltic Sea) and South Stream (Black Sea) projects. In addition, the bottom topography, the location of the pipeline, and the accumulation of methane bubbles due to leaks from the pipeline are taken using sonar tools from underwater probe 8. Quantification of methane bubbles It is produced according to various algorithms depending on the structure and density of accumulations of methane emissions from the pipeline.

The quantitative estimation algorithm in the general case determines the transition from the number of echo signals to the absolute value - the number of bubbles, for which a normalized value is calculated - the average density of the accumulation of bubbles. In this case, the patterns of depth distribution of bubble cluster density are determined by dividing the range into layers and calculating the bubble density for each layer.

In particular, the quantitative characteristics of discharged clusters of methane bubbles are estimated based on the well-known expression for the average density of a discharged cluster (echo counting method):

,

,

where K ₁ is the number of echo signals from bubbles from layer 1; S ₁ - section of the sonar area, m ² ; H is the thickness of the cluster, m; Q is the repetition rate of the emitted signals; T is the time of sounding the cluster; m is the number of layers.

For the implementation of quantitative estimation algorithms, the used hydroacoustic means possess the necessary technical characteristics (table 1).

Table 1 Technical characteristics of sonar Specifications Sounder path Side View Sonar Path Parametric Profiler Working frequency, kHz 204 286 and 320 10 and 150 The width of the directivity, degrees. 6 × 10 and 12 × 20 1.5 × 50 and 3 × 50 3 × 4 Pulse Duration, μs 50, 200, 500 50, 100, 1 0.5, 1.2 Ranges, m 5, 10, 20, 50, 100, 200 5, 10, 20, 50, 100, 200 5, 10, 20, 50, 100, 200

Fishfinder 26 is designed to search for clusters of methane bubbles, quantification and profiling of the bottom. The side-scan sonar 28 is designed to capture the bottom topography, search and quantify clusters and single bubbles. The high-frequency profilograph 33 is designed for accurate profiling of the bottom topography at the leak site. Low-frequency profilograph 31 is designed for profiling bottom sediments.

The microcomputer 23 is designed to control the operation of hydroacoustic means and is connected through the port to a satellite communication channel receiver.

The methane detection sensor 39 is a METS ("CAPSUM") type sensor that measures the concentration of methane in the water column. The sensor is a semiconductor device, the principle of which is that the diffusion of hydrocarbon molecules from water through a special silicone membrane is transmitted to the sensor chamber. Adsorption of carbohydrate molecules on the active layer of the sensor leads to electronic exchange with oxygen molecules, thus changing the resistance of the active layer, which is converted into output (measured) voltage.

Key Features of Methane 39 Detection Sensor:

- 10 μm silicone membrane;

- working depth 0-3500 m;

- operating temperature 2-20 degrees C;

- measurement time from 1 to 3 seconds;

- diffusion stabilization time up to 5 minutes, depending on turbulence;

- input voltage 9-36 V;

- power consumption 160 mA / h;

- output signal - analog 0-5 V and digital RS - 485;

- methane 50 nmol / l - 10 μmol / l.

The wind speed and direction sensor 22 of type ДСНВ-9 contains a measuring transducer and two anemometric measuring sensors: - wind speed (anemometer) and wind direction (weather vane). The wind speed sensor consists of a three-cup impeller rotated by the wind. A perforated disk with holes is installed on one axis with the impeller, which, when the impeller rotates, blocks the light beam of the optoelectronic converter. The frequency of the pulses generated by the optoelectronic converter is proportional to the speed of rotation of the impeller.

The sensitive element of the wind direction sensor is a weather vane, oriented in the direction of the wind. A perforated disk with holes is mounted on the axis of rotation. The optoelectronic converter takes a readout of the angular position of the disc in increments of 5.6 ° and provides a digital code for the position of the wind vane in the form of a Gray code. The measuring converter converts discrete readings into a linearly varying current for current measuring channels of speed and wind direction in the BP-3 unit.

The wind speed and direction sensor 22 contains a heating element that includes a thermal relay when the temperature drops below 4 ° C and maintains the necessary operating temperature inside the sensor and eliminates the formation of ice.

The atmospheric pressure sensor 19 type DAD-5 is a digital barometer, the sensitive element of which is a silicon diaphragm, which works on the principle of converting atmospheric pressure into frequency.

The temperature and relative humidity sensor 17 contains a measuring transducer and sensitive elements (a platinum resistance sensor and a quartz humidity transducer of capacitive type).

Temperature and humidity alter the resistance value and capacitance of the transducer of the sensing element and are converted by the measuring transducer into linearly varying analog signals proportional to the measured temperature and humidity.

A sensor developed by the Federal State Unitary Enterprise OKB Oceanological Engineering RAS, having a pressure measurement range from 0 to 10 m, with an accuracy of 0.1% and a measurement range of water temperature from -2 to +32 degrees C, was used as a pressure and temperature sensor for water 20 and 37, with an error of 0.05 degrees C.

The receiving station 7 is made in the form of a spherical surface and is equipped with a sailing device 10 in the lower part, which includes eight planes located in a vertical plane, equipped with floats in the lower part to ensure neutral buoyancy when the receiving station is in the methane cloud propagation zone. In the upper part, the sailing device is articulated with a rotary device, driven by a micromotor with a gearbox, which also serve to lower and raise the underwater probe 8 to a predetermined depth by means of a winch. Sailing device 11 also performs the function of a stabilizer under external influences.

To move the receiving station 7 along the pipeline route, it is equipped with a rotary plate propeller.

Commands for the operation of the receiving station and the equipment installed on it are given from the control panel 4 of the marine terminal 5 via a satellite communication channel.

The control panel 4 of the marine terminal, through satellite channels, receives signals from the receiving station 7 and is an information-computing system that includes an electronic digital map module in accordance with the requirements of IMO Resolution A. 817/19, which displays the topography of the bottom with a pipeline, cloud accumulations gas leaks. The computer system also includes a satellite navigation module, which, based on the signals received from the satellite, calculates the trajectory of the receiving station relative to the pipeline route.

Information is transmitted from receiving stations to the control panel according to the following algorithm. At each i-th receiving station, the measured values of the j parameters of the ocean are converted into digital codes, a digital message is generated containing the i-th number of the receiving station and the measured values of j parameters of the atmosphere, the ocean in digital form, generate a high-frequency oscillation at the frequency ωi, manipulate it by phase by a digital message and the generated complex signal with phase shift keying is amplified by power and radiated into the air, and at each control point, a serial search and conversion of signals by frequency is performed, highlighting t is a complex signal with phase shift keying at an intermediate frequency, its frequency detection is carried out, as a result of which short unipolar pulses are emitted, corresponding to the moments of a step-like phase change of a complex signal with phase shift keying, they form a bipolar voltage in the forward and reverse code proportional to the digital message, register and analyze it, as a result of which the i-th number of the receiving station and the values of j parameters of the ocean are determined.

On the control panel 4 of the sea terminal 5, according to the information received from the diagnostic modules, taking into account the information from the preliminary target monitoring performed according to the previous current data, taking into account the operational safety criteria of the pipeline, a comparative analysis of stationary and dynamic processes is carried out, anomalous areas are identified, a development forecast is made situations by constructing parametric models of pairwise comparisons; when new anomalous points appear during the registration process, the forecast is adjusted based on adaptive methods for predicting estimates; Based on the forecast of the development of anomalous processes in the research areas along the pipeline route, the degree of risks affecting the safe functioning of the pipeline is determined by the method of expert assessments expressed by rankings, while the consistency of the rankings is checked using the Kendall and Spearman rank correlation coefficients, the Kendall rank concordance coefficient and Babington Smith and the parametric model of paired comparisons - Thurstone, Bradley-Terry-Lews - and nonparametric models of the theory of Lucians [A .Koffman. Introduction to the theory of fuzzy sets. M .: Radio and communication, 1982, 432 pp.], Which allows for point and interval estimation of parameters, to check the significance of their difference from 0 in a nonparametric setting, and to build confidence boundaries for the forecast. The main processing procedures for prognostic expert assessments are consistency checking, cluster analysis of research results.

The inventive method for diagnosing trunk pipelines and a device for its implementation can be used to diagnose and detect leaks from trunk pipelines laid at the bottom of the seas and intended for transportation of natural gas and oil. The presence in the device hydroacoustic means for detecting inhomogeneities allows you to use this technical solution to detect leaks from pipelines laid on the seabed of the shelf of the Arctic seas in the presence of ice, which is practically not provided by known methods.

The implementation of the claimed technical proposal does not present technical difficulties, since the sensors for measuring physical quantities have industrial applicability, which allows us to conclude that the claimed technical solution meets the patentability condition "industrial applicability".

Claims (2)

1. A method for diagnosing trunk pipelines laid at the bottom of reservoirs, characterized in that the external surface of the pipeline is probed with hydroacoustic signals, the methane concentration in the gas cloud is determined by the methane sensor by measuring the change in the active layer of the methane sensor during the diffusion of hydrocarbon molecules from sea water through a silicone membrane , determine the laws of the distribution of the density of the accumulation of gas bubbles in depth by distributing the range into layers with the calculation of the density the accumulation of gas bubbles for each layer in depth, they evaluate the quantitative characteristics of rarefied gas accumulations, while the number of receiving stations satisfies the condition of filling the studied area along the pipeline route, transmitting information from the receiving stations to the control panel, and the measured values of parameters at each receiving station the oceans are converted into digital codes, form a digital message containing the number of the receiving station and the measured values of the parameters of the atmosphere, the ocean in in the digital form, they generate a high-frequency oscillation at the carrier frequency, manipulate it in phase with a digital message and the generated complex signal with phase manipulation is amplified in power and radiated into the air, and at each control point, the signals are sequentially searched and converted in frequency, a complex signal with phase by manipulation at an intermediate frequency, its frequency detection is carried out, as a result of which short unipolar pulses are emitted, which correspond to moments in steps phase change of the complex signal with phase shift keying, they are used to generate a bi-polar voltage in the forward and reverse code proportional to the digital message, register and analyze it, as a result of which the number of the receiving station and the values of the ocean parameters are determined, the monitoring area is monitored on the control panel using stock and / or archival information and recorded signals with the formation of a database including information about the bottom topography, stationary and abnormal hydrodynamic processes, hydroacoustic soundings with subsequent restoration of the relief of the environment, while the emission and reception of signals are performed according to the method of multiple overlapping or identical soundings, isolate fluctuations of anomalous signals at the background levels of the natural environment, perform a comparative analysis of stationary and dynamic processes, identify abnormal areas, make a forecast of the situation by constructing parametric models of pairwise comparisons; when new anomalous points appear during the registration process, the forecast is adjusted based on adaptive methods for predicting estimates; Based on the forecast of the development of anomalous processes in the field of research, the degree of risks affecting the safe operation of the pipeline is determined by the method of expert assessments expressed by rankings, while the consistency of the rankings is checked using the Kendall and Spearman rank correlation coefficients, the Kendall and Babington Smith rank concordance coefficient and the parametric paired comparison models - Thurstone, Bradley-Terry-Lews - and nonparametric models of the Lucian theory. 2. A device for implementing the method, which is a locator for viewing the pipeline, strain gauges and mechanical displacements installed on the surface of the pipeline and connected to the control panel, characterized in that the locator for viewing the pipeline is made in the form of a sonar system, including an echo sounder, side sonar review, high-frequency and low-frequency profilographs, satellite navigation system, an additional sensor for determining the concentration of methane, and the hydroacoustic the methic system and the methane sensor are connected via a cable to a receiving station located on the surface of the water and articulated with a stabilizing device made in the form of an underwater sail and equipped with a satellite communication channel and propulsion device; the methane sensor and receiving-emitting devices of the hydroacoustic system (echo sounder antenna, side-scan sonar, pumping of parametric profilographs) are located in the outboard part of the receiving station, which is made in the form of an underwater probe.

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