RU2476747C2 - Method of measurement of direction and speed of soil movement relative to underground pipeline and device for its implementation - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: according to the method electrodes of two electrode spreads are arranged near underground pipeline along two transversely-spaced profiles one of which coincides with the pipeline axis. Direct current electrode common for both electrode spreads is rigidly connected to the underground pipeline providing its electrical insulation. The first and the second pairs of measuring electrodes of both electrode spreads are located on different sides from the direct current electrode, and return current electrode is located at a distance, for example from 1 to 10 metres, from the measuring electrodes. Alternating current is supplied to the circuit of direct and return current electrodes, and potentials difference between electrodes of the first and the second pairs of the measuring electrodes are measured. As a controlled parameter relation of potentials differences of the first pair of measuring electrodes to potentials difference of the second pair for both electrode spreads. Based on dependence of potentials difference relations on movements of measuring electrodes relative to the underground pipeline obtained by means of calculations or by experiment, movement of soil along and across the pipeline, direction and speed of its movement are determined. The device implementing the method includes measuring, direct and return electrodes of two electrode spreads, alternating current generator, potentials difference measuring device, data processing and control unit, switchboard, information transfer channel. The first and the second pairs of measuring electrodes of both electrode spreads are installed on rigid insulating plates and are located on different sides from direct current electrode.

EFFECT: recording direction and speed of soil movement relative to the pipeline in automatic mode to detect emergency timely and to take measures to protect the pipeline.

3 cl, 3 dwg

Description

The invention relates to the oil and gas industry and can be used in the operation of pipelines located in landslide massifs to take timely measures to protect pipelines during soil movements caused by the violation of the weight balance as a result of seasonal thawing, soil saturation with water or other reasons.

A known method of measuring the direction and speed of movement of the soil relative to the underground pipeline and a device for its implementation, which consists in the fact that along the axis of the pipeline set at a certain distance from each other benchmarks and measure angular and linear deviations of the benchmarks from their original position, the value of which is judged about the direction and speed of the soil, while continuously registering the direction of movement of the soil relative to the axis of the pipeline and the speed of movement of the soil relative a fixed section of the pipeline by mounting directly on conduit devices which convert respectively the angular and linear displacement to an electrical ground signal to the input of the measuring unit. (Patent RU No. 2153118, class F16L 1/028, published on July 20, 2000).

The disadvantage of this method is that information about the direction and speed of movement of the soil can be obtained from converting devices only in bulk soils. In cohesive soils, devices implementing the method are inoperative.

A known method of measuring the direction and speed of soil movement of the trench of the pipeline, which consists in the fact that along the axis of the pipeline set the reference frame at a certain distance from each other and measure the angular and linear deviations of the frames from their original position, the value of which is used to judge the direction and speed of movement of the soil .

Benches are made of metal pipes with a diameter of 100-120 mm and a length of up to 2-3 meters. The spatial position of the benchmarks is recorded using a theodolite, for the installation of which a special site is prepared, located away from the pipeline and keeping its position in space unchanged during the observation time. The determination of the direction and speed of soil movement is carried out according to the theodolite readings obtained in the initial state and taken as zero and theodolite readings obtained during subsequent periodic measurements of the position of the benchmarks. (Handbook of a civil engineer under the editorship of Anuryev N.A. et al., M., publishing house of construction literature, 1970, vol. 2, half I, p. 212).

The disadvantage of this method is that it is unsuitable for automatic continuous monitoring of soil movement, for example, using automatic stations monitoring the state of the landslide massif.

A device for measuring electrical resistivity of rocks in the form of an electric prospecting station ERSU-61, including measuring and direct and reverse current supply electrodes, a power supply generator, a switch, a potential difference meter in the form of a measuring panel IPO, a control unit (control panel), channel information transfer (PC station). (Electrical Exploration, Yu.V. Yakubovsky, M., "Nedra", 1980, p.132, 144-145).

The known device cannot measure the direction and speed of soil relative to the pipeline, especially in automatic mode.

The objective of the proposed group of inventions is to increase the efficiency of obtaining information about soil movements in the continuous automatic control mode.

The essence of the first invention lies in the fact that in the known method of measuring the direction and speed of movement of the soil relative to the underground pipeline, which consists in the fact that near the pipeline set at a certain distance from each other benchmarks and periodically measure their parameters and deviations from the original values, by values which are judged on the direction and speed of the soil, according to the invention, benchmarks are used as electrodes of two electrical prospecting installations, placed in two m mutually perpendicular profiles, one of which coincides with the axis of the pipeline, moreover, the direct current reference electrode common to both electrical prospecting installations is rigidly connected to the underground pipeline, providing its electrical insulation, the first and second pairs of measuring reference electrodes of both electrical prospecting installations on opposite sides of the direct current reference electrode, the reverse current reference electrode is carried by a distance not less than ten times the distance between the centers of the first and the second pair of measuring reference electrodes, pass alternating current in the circuit of the forward and reverse current reference electrodes, measuring the potential differences between the electrodes of the first and second pairs of measuring reference electrodes of both electrical exploration installations, and using the ratio of the potential difference of the first pair of measuring reference electrodes to the potential difference of the second pair for both electrical prospecting installations and according to the dependences of the relations of potential differences from displacements from measuring reference electrodes relative to the underground pipeline, obtained by calculation or experimentally, determine the movement of soil along and across the pipeline, the direction and speed of its movement.

The essence of the second invention lies in the fact that in the inventive device for measuring the direction and speed of movement of the soil relative to the underground pipeline, which includes direct and reverse current and measuring electrodes-reference electrodes of electrical exploration installations, an alternating current generator, a potential difference meter, a control and processing unit data, a switch, a channel for transmitting information, while the forward and reverse current reference electrodes are connected to the output of the alternator a, the measuring electrodes are connected to the inputs of the switch, the outputs of which are connected to the input of the potential difference meter connected to the input of the control and data processing unit, controlling the switch and the alternator, the outputs of the control and data processing unit are connected to the inputs of the information transmission channel, according to the invention, reference electrodes of electrical prospecting installations are placed along two mutually perpendicular profiles, one of which in the direction coincides with the axis of the pipeline, and the straight line then Marketing electrode frame is common to both electro plants and placed on the electrically insulating base, fixed to the underground pipe, the first and second pair of measurement electrodes two electro-frame units are mounted on rigid insulating plates and disposed on either side of the direct-current electrode frame.

Figure 1 shows the layout of the reference electrodes near the underground pipeline.

Figure 2 shows the design of electrical exploration installations of the device for measuring the direction and speed of movement of the soil relative to the underground pipeline.

Figure 3 presents a functional diagram of a device for measuring the direction and speed of movement of soil relative to an underground pipeline.

Figure 4 shows the calculated and experimental dependences of the ratio of the potential difference of the first pair of measuring reference electrodes and the potential difference of the second pair of measuring reference electrodes.

Figure 1 shows the underground pipeline 1, profile 2, perpendicular to the axis of the pipeline 1, profile 3, parallel to the axis of the pipeline 1, direct current electrode reference 4, the first pair of measuring electrodes reference 5 of the first electrical exploration installation, the second pair of measuring electrodes reference 6 , the first pair of measuring reference electrodes 7 of the second electrical exploration installation, the second pair of measuring reference electrodes 8 of the second electrical prospecting installation, the reverse current electrode-reference 9.

Both electrical prospecting installations of the device for measuring the direction and speed of movement of the soil (Fig. 2) have a common current reference electrode 4, located on the electrical insulating base 10, mounted on the underground pipeline 1. The reference electrode 4 is attached to the electrical insulating base 10 with a screw 13. The first 5 , 7 and second 6, 8 pairs of measuring reference electrodes of both electrical prospecting installations are mounted on rigid electrical insulating plates 11, 12, respectively, and are located on opposite sides of the direct current reference electrode 4. The longitudinal axis of the plates 11, 12 are mutually perpendicular and the axis of the plate 12 parallel to the axis of the underground pipeline 1.

The reverse current reference electrode 9 is spaced from the measuring electrodes by a distance ten times the distance between the centers of the pairs of measuring reference electrodes.

A device for measuring the direction and speed of soil movement (Fig. 3) also includes an alternating current generator 14, a potential difference meter 15, a control and data processing unit 16, a switch 17, an information transmission channel 18.

Forward and reverse current reference electrodes 9 are connected to the outputs of the alternator 14, pairs of measuring reference electrodes 5, 6, 7, 8 are connected to the inputs of the switch 17, the outputs of which are connected to the input of the potential difference meter 15 connected to the input of the control unit and data processing 16, the control switch 17 and the alternator 14, the outputs of the control unit and data processing 16 are connected to the inputs of the information transfer channel 18.

The method of measuring the direction and speed of the soil is as follows. Above the underground gas pipeline, reference electrodes of two electrical prospecting installations are placed along two mutually perpendicular profiles 2, 3 (Fig. 3), one of which (3) coincides in the direction with the axis of the pipeline. The direct current reference electrode 4 is rigidly connected to the underground pipeline 1, ensuring its electrical isolation from the pipeline. The first 5, 7 and second 6, 8 pairs of measuring reference electrodes of both electrical prospecting installations are placed on opposite sides of the direct current reference electrode 4, and the reverse current reference electrode is carried by a distance not less than ten times the distance between the centers of the first 5, 7 and the second 6, 8 pairs of measuring reference electrodes.

The distance between the centers of the pairs can be selected depending on the specific conditions from 1 to 10 m.

An alternating current is passed through the direct 4 and 9 reverse circuits of current reference electrodes and potential differences between the measuring reference electrodes of the first (5, 7) and second (6, 8) pairs of measuring reference electrodes of both electrical prospecting installations are measured.

Make up relationship

where ΔU ₁₁ , ΔU ₂₁ are the potential differences of the first 5 and second 6 pairs of measuring electrodes of the first electrical exploration installation;

ΔU ₁₂ , ΔU ₂₂ - potential differences of the first 7 and second 8 pairs of measuring electrodes of the second electrical prospecting installation.

и

By Dependencies

and

where S1 and S2 are soil displacements in the directions of mutually perpendicular profiles 2, 3, the corresponding soil displacements are determined.

и

могут быть получены расчетным путем или экспериментально путем установления зависимости изменения отношения разностей потенциалов при дискретных синхронных перемещениях первой и второй пар измерительных электродов относительно неподвижных прямого и обратного электродов. На фиг.4 приведен вид таких зависимостей.Dependencies

and

can be obtained by calculation or experimentally by establishing the dependence of the change in the ratio of potential differences during discrete synchronous movements of the first and second pairs of measuring electrodes relative to the stationary forward and reverse electrodes. Figure 4 shows a view of such dependencies.

As you know, the potential difference that arises between a pair of measuring electrodes of an electrical exploration installation when passing current through the ground is determined by the expression:

where I is the current value;

S is the electrical resistivity of the soil;

K is the coefficient of the electrical exploration installation, depending only on its geometric dimensions and configuration.

равно обратному отношению коэффициентов электроразведочных установок и не зависит от удельного электрического сопротивления грунта и тока питания. При движении грунта и соответственно пар измерительных электродов-реперов относительно неподвижного прямого токового электрода будут изменяться коэффициенты K₁ и К₂, причем в противоположных направлениях, так как пары измерительных электродов расположены по разные стороны от токового электрода. Следовательно, при движении пар электродов вместе с грунтом будут меняться и отношения разностей потенциалов (фиг.4).Thus, the ratio of potential differences of two pairs of measuring electrodes

equal to the inverse ratio of the coefficients of electrical prospecting installations and does not depend on the specific electrical resistance of the soil and the supply current. When the ground moves and, accordingly, the pairs of measuring reference electrodes with respect to the fixed direct current electrode, the coefficients K ₁ and K ₂ will change, and in opposite directions, since the pairs of measuring electrodes are located on opposite sides of the current electrode. Therefore, when the pairs of electrodes move along with the soil, the potential difference ratios will also change (Fig. 4).

The vector of the total soil displacement in a rectangular coordinate system associated with the axis of the pipeline and the direction perpendicular to it can be represented as:

,

- единичные орты по соответствующим координатным осям.Where,

,

- unit vectors along the corresponding coordinate axes.

Mix vector module:

и осью трубопроводаThe direction of movement of the soil is determined by the angle α between

and the axis of the pipeline

Ground Speed:

where T is the time between measurements.

A device for measuring the direction and speed of the soil works as follows.

From the alternator 14 by command from the control and data processing unit 16, direct current 4 and reverse 9 current electrodes are supplied with alternating current. Between the electrodes of four pairs of 5, 6, 7, 8 measuring electrodes, potential differences ΔU ₁₁ , ΔU ₂₁ , ΔU ₁₂ , ΔU ₂₂ occur, which are fed to the corresponding inputs of the switch 17, which, by commands of the control and data processing unit 16, alternately connects the pairs of measuring electrodes to the input of the potential difference meter 15.

The potential difference meter 15 converts the input variable voltage to DC voltage, which are fed to the input of the control and data processing unit 16, where they are digitized and fed to the inputs of the information transfer channel 18.

Information via telemetry channels is transmitted to the control room, where it is processed according to appropriate algorithms to obtain information about the direction and speed of movement of the soil relative to the underground pipeline.

Measurements are made automatically at intervals determined by the program of the control unit and data processing 16, which is based on a microprocessor.

To ensure the constancy of the distances between the measuring electrodes, they are installed on the insulating plates 11, 12 (figure 2). A direct current electrode 4 is also installed on the insulating base 10 to eliminate the possible influence of the pipeline in case of violation of its insulation on the measurement results.

If the direction of movement of the soil is known, then to determine its speed of movement, only one electrical prospecting installation is sufficient, the current and measuring electrodes of which are placed on a profile that coincides with the direction of movement of the soil.

The proposed method and device allows to automatically automatically record the direction and speed of soil movement relative to the pipeline and evaluate the magnitude of the additional loads acting on the pipeline, which allows timely detection of emergency situations and take timely measures to protect the pipeline from destruction.

Claims (2)

1. The method of measuring the direction and speed of movement of the soil relative to the underground pipeline, which consists in the fact that near the pipeline set at a certain distance from each other benchmarks and periodically measure their parameters and deviations from the original values, the values of which judge the direction and speed of movement of the soil characterized in that the reference points are used as electrodes of two electrical exploration installations placed along two mutually perpendicular profiles, one of which coincides with the axis of the pipeline, and the direct current reference electrode common to both electrical prospecting installations is rigidly connected to the underground pipeline, ensuring its electrical isolation, the first and second pairs of measuring reference electrodes of both electrical exploration installations are located on opposite sides of the direct current reference electrode , the reverse current reference electrode is carried to a distance not less than ten times the distance between the centers of the first and second pairs of measuring reference electrodes, alternating current in the circuit of the forward and reverse current reference electrodes, measure the potential difference between the electrodes of the first and second pairs of measuring reference electrodes of both electrical exploration installations, and use the ratio of the potential difference of the first pair of measuring reference electrodes to the potential difference of the second pair for both electrical prospecting installations and according to the dependences of the relations of potential differences from the displacements of the measuring reference electrodes relative to the underground boprovoda obtained by calculation or experimentally determined soil displacement along and across the pipeline, the direction and speed of its movement. 2. A device for measuring the direction and speed of movement of the soil relative to the underground pipeline, including direct and reverse current and measuring electrodes-reference electrodes of electrical exploration installations installed near the pipeline, an alternating current generator, a potential difference meter, a control and data processing unit, a switch, an information transmission channel, in this case, the forward and reverse current reference electrodes are connected to the output of the alternator, the measuring electrodes are connected to the inputs of the switch the odes of which are connected to the input of the potential difference meter connected to the input of the control and data processing unit that controls the switch and the alternator, the outputs of the control and data processing unit are connected to the inputs of the data transmission channel, characterized in that the reference electrodes of the electrical exploration installations are located in two mutually perpendicular profiles, one of which coincides in the direction with the axis of the pipeline, moreover, a direct current reference electrode is common to both electrical prospecting x installations and placed on an insulating base mounted on an underground pipeline, the first and second pairs of measuring electrodes-benchmarks of both electrical prospecting installations are mounted on rigid electrical insulating plates and are located on opposite sides of the direct current reference electrode.

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