RU87532U1 - IN-TUBE ELECTROMAGNETIC-ACOUSTIC SCANNER - Google Patents

Abstract

An in-line electromagnetic-acoustic scanner containing a housing (yoke), at the ends of which are locomotor elements, a magnetizing system, made in the form of two magnetizing belts of permanent magnets mounted on the housing, brushes are fixed at the ends of which, permanent magnets in each magnetizing the belts have a radial but opposite magnetization, a measuring system located between the magnetizing belts, containing two electromagnetic-acoustic belts, each the first of which contains receiving and emitting electromagnetic acoustic sensors located evenly around the perimeter, which are pressed with elastic elements to the inner surface of the pipeline, receiving and emitting electromagnetic acoustic sensors are located at an angle of 45 ° to the magnetization vector, and adjacent receiving and emitting electromagnetic the acoustic sensors in each of the measuring zones are orthogonal to each other, and each of the receiving-emitting electromagnetic acoustic sensors is made in the form of a layer APIS on which the planar radiating and receiving coil wound in a meandering manner, wherein the meander shoulder substantially smaller lateral edge which provides a directivity pattern of reception and radiation of signals.

Description

The utility model relates to devices for monitoring the state of long pipelines, namely, to determine defects in the walls of oil and gas pipelines by passing a diagnostic projectile inside the pipeline being examined, recording acoustic scanning data in the on-board computer, and then determining the parameters of the pipeline defects from the accumulated data.

A known method of excitation and reception of ultrasonic waves and a device for its implementation (USA, patent 4100809, op. 18.07.1978). The device comprises a movable platform on rollers, which moves along the pipe. A magnetizing system and an electromagnetic acoustic measuring system are installed on a moving platform. The magnetizing system contains a magnet, an S-shaped magnetic circuit, consisting of a central rod and two side rods. Two counterclockwise magnetizing coils are mounted on the central shaft. Pole lugs are installed at the ends of the side rods, each of which is made in the form of a platinum package with an adjustable curvature of the working surface. Side rods are rotatable around the axis of the central rod. An electromagnetic acoustic measuring system is located on the guide, between the pole pieces and symmetrically to the axis of the central rod and is two high-frequency inductors. The high-frequency coil has a flat rectangular shape, and the projection of the coil turns on a plane has the shape of a meander, where the shoulder of the meander is substantially smaller than the side rib.

The device is based on the electromagnetic-acoustic (EMA) method of exciting and receiving ultrasonic vibrations. The device operates as follows. The device is installed on a controlled pipe and moved along it. By turning the side rods around the hinge axes and giving the tips a pipe curvature, a magnetizing belt of an electromagnet is formed. Turn on the power of magnetizing coils and transducers. A permanent magnetizing field is induced through the tips in the pipe walls, which makes up a certain angle with the direction of the converter radiation, depending on the relative position of the transducers and the pole pieces. By changing the relative position of the pole pieces and transducers, normal longitudinal waves, normal transverse waves, or both types of waves can be excited simultaneously in the pipe body.

To control the wide zone of the pipe using the shadow method, a central tip of a rectangular shape and pole pieces are installed in line with the transducers. In the shadow method of controlling longitudinal normal waves of the local zone of the pipe, the location of the pole pieces and transducers is the same, but the central pole piece has a round shape, and the focusing transducers are installed. In the shadow method of control by transverse normal waves, the angle between the direction of radiation of the transducer and the direction of the magnetizing field is 20-60 °. This is achieved by the fact that the pole pieces are arranged so that the direction of the magnetizing field with the measurement direction is 20-60 °. The angle between the vector of the bias field and the direction of radiation radiation is selected in accordance with the dependences of the amplitudes of the longitudinal waves and the transverse waves for this angle so that the high-frequency inductors emit transverse or longitudinal normal waves or both types of waves simultaneously.

The disadvantage of this device is that the device is designed to measure defects outside the pipeline and thus does not allow you to work with already laid pipelines. In addition, the emitter and receiver are located at one point, which allows you to receive only one echo signal. This configuration of the system of electromagnetic-acoustic sensors allows you to determine the presence of defects, but does not allow you to determine the size and configuration of the defect, and the types of cracks located along the movement of the wave front are not recorded.

The closest in design to the claimed utility model is an in-line ultrasonic projectile for determining wall thickness (US patent 7111516, op. September 26, 2006).

The device comprises a housing, at the ends of which are located locomotor elements, and an acoustic measuring system made in the form of two acoustic belts, each of which contains acoustic modules, including receiving and emitting ultrasonic sensors, spring-loaded with flexible elastic elements to the pipe wall. The housing forms an explosion-proof shell, in which the power source and electronic equipment for measuring, processing and storing the obtained measurement data are located on the basis of the on-board computer that controls the operation of the projectile during its movement inside the pipeline. Rechargeable batteries or batteries of galvanic cells with a capacity of up to 1000 Ah are installed as a power source. Ultrasonic sensors are installed in the tail of the projectile, alternately emitting and receiving ultrasonic pulses. Polyurethane cuffs installed on the shell of the projectile provide centering of the projectile inside the pipeline, as well as ensure the advancement of the projectile by the medium pumped through the pipeline. The wheels of the odometers installed on the flaw detector body are pressed against the inner wall of the pipeline. When the projectile moves, the information on the distance traveled, measured by odometers, is recorded in the on-board computer drive and allows, after performing a diagnostic pass and processing the accumulated data, to determine the position of defects in the pipeline and, accordingly, the place of subsequent excavation and repair of the pipeline.

The electronic part of the flaw detector in the simplest version includes a serially connected trigger pulse generator, a sensor, an amplifier, a differentiating circuit, a comparator, a digital counter, a processor, a digital data storage device, as well as a reference voltage source and a clock generator.

The device operates as follows. The flaw detector is placed in the pipeline and includes pumping the product (oil, oil) through the pipeline. During the movement of the in-tube ultrasonic flaw detector inside the pipeline, ultrasonic sensors periodically emit ultrasonic pulses with a frequency of 5 MHz, which are partially reflected from the inner wall of the pipeline, from the outer wall of the pipeline or from the area of the defect, for example, delamination of the metal in the pipe wall. After emitting ultrasonic pulses, the ultrasonic sensors switch to the reflected pulse mode and receive pulses reflected from the inner wall, pulses reflected from the outer wall of the pipe, or pulses reflected from the area of the wall defect.

Upon completion of control of a given section of the pipeline, the flaw detector is removed from the pipeline and the data accumulated during the diagnostic pass is transferred to a computer outside the projectile. Subsequent analysis of the recorded data allows you to identify defects in the wall of the pipeline and determine their position on the pipeline for the subsequent repair of defective sections of the pipeline.

The main disadvantage of this device is that it works only in liquid media, for example, in oil pipelines. The projectile cannot work in gas pipelines.

The essence of the utility model is that the in-line electromagnetic-acoustic scanner contains a housing (yoke), at the ends of which are locomotor elements, a magnetizing system, made in the form of two magnetizing belts of permanent magnets mounted on the housing, at the ends of which brushes are fixed, moreover, the permanent magnets in each of the magnetizing belts have a radial but opposite magnetization, a measuring system located between the magnetizing belts containing electromagnetic-acoustic belts, each of which contains receiving-emitting electromagnetic-acoustic sensors located uniformly around the perimeter, which are pressed with elastic elements to the inner surface of the pipeline, receiving-emitting electromagnetic-acoustic sensors are located at an angle of 45 ° to the magnetization vector, adjacent receiving and emitting electromagnetic acoustic sensors in each of the measuring zones are orthogonal to each other, and each of the receiving and emitting electromagnetic The acoustic sensors are made in the form of a plate on which there are flat receiving and radiating windings wound in the form of a meander, where the meander arm is substantially smaller than the side rib, which provides a radiation pattern of the reception and emission of signals.

The two-row arrangement of receiving and emitting electromagnetic acoustic sensors, as well as their location at an angle of ± 45 ° to the magnetization vector, allows, by means of an orthogonal four-position scanning, to obtain 16 projections of the ultrasound image of each defect. Accordingly, 12 projections of reflected signals and 4 projections of signals transmitted through a defect during ultrasonic radiation from 4 different directions. The received signals after processing using special programs allow you to get a graphic image of the defect and its parameters. The described process resembles x-ray tomography.

A detailed description of the design of the device and its operating principle is illustrated by drawings.

Figure 1 shows a General view of the device;

figure 2 shows the device, side view;

figure 3 shows a cross section of the upper part of the device, stocked in a pipeline with two measuring belts;

figure 4 is a scan of the pipe with two magnetizing belts and two measuring belts of electromagnetic acoustic sensors;

figure 5 presents the design of the electromagnetic acoustic sensor;

figure 6 shows the geometry of the emitting and receiving EMA coils mounted with a radiation pattern at an angle of 45 ° to the direction of permanent magnetization of the field, and the formation of a normal transverse ultrasonic wave in the pipe body;

Fig.7 is an electrical block diagram of the device.

The device is structurally made in the form of an in-tube projectile and comprises a cylindrical body (yoke) 1 made of soft magnetic material (Figs. 1, 2, 3). On the end faces of the housing 1, locomotor elements 2 are installed, which provide centering of the device in the pipeline and bear the weight of the device. The pressure difference created by the snug fit of the musculoskeletal elements 2 to the walls 3 of the pipeline ensures the movement of the device in the pipeline under examination by the flow of the product transported through it. Musculoskeletal elements 2 can be made in the form of cuffs made of wear-resistant polyurethane of high strength, or in the form of discs also made of polyurethane. A bracket 4 and a cowl are fastened in the bow of the device. At the ends of the supporting-motor elements 2, rollers 6 and odometer sensors 7 can be installed. Bracket 4 is used for transport and loading operations, for installing the device in the pipeline, as well as for coupling it with an additional measuring device when creating a multi-section device. Inside the housing 1, there are means for controlling the speed of the projectile in the form of an adjustable bypass pipe for bypassing the product transported through the pipeline, and additional measuring sensors are placed (not shown in the drawings).

The magnetizing system of the device consists of yoke 1 and two magnetizing belts, each of which contains a belt of permanent magnets, respectively 10 and 11, mounted on yoke 1, and a belt of flexible magnetic brushes, respectively 12 and 13, mounted on the ends of magnets 10 and 11. Direction The magnetization in the permanent magnets 10 and 11 is mutually opposite and directed radially from the yoke 1 to the pipe 3 (figure 3).

Between the magnetizing belts there is a measuring system containing two measuring belts, each of N receiving-emitting electromagnetic-acoustic (EMA) sensors, respectively 14 and 15. The receiving-emitting electromagnetic-acoustic sensors 14 and 15 are located uniformly around the perimeter and are pressed against the inner surface pipeline 3 using elastic elements ("fins"), respectively 16 and 17 (figure 3).

Structurally, each of the N receiving-emitting electromagnetic acoustic (EMA) sensors 14.1-14.N and 15.1-15.N, respectively, of the first and second measuring belts is a flat plate 18 on which a flat radiating winding T and a flat receiving winding R are made (Figure 5). The high-frequency radiating T and receiving R windings have a flat rectangular shape, and the projection of the turns of the windings on the sensor plane has the shape of a meander, where the shoulder of the meander is substantially smaller than the side rib. Thus, the side ribs determine the radiation pattern and the reception of electromagnetic acoustic waves, and the axis of the radiation pattern is perpendicular to the side rib and passes in the middle of the high-frequency windings T and R (Figs. 5, 6).

In each of the zones, electromagnetic-acoustic sensors 14 and 15 are installed so that their radiation pattern is located at an angle of 45 ° to the magnetization vector. Moreover, adjacent sensors in each of the zones are orthogonal to each other (figure 4).

Inside the housing 1 (Fig. 7), an onboard power supply unit 8 and a computer 9 are located. The power supply unit 8 contains a battery section 19, a module 20 for converting the battery voltage into a voltage necessary for supplying electronic modules, an intrinsic protection module 21, and a power distribution module 22. An electrical output the battery section 19 is connected to the input of the voltage conversion module 20, the outputs of which are connected through the spark protection module 21 to the power distribution module 22. The outputs of the power distribution module 22 are connected to all electronic modules and electronic cops device. The on-board computer 8 includes a processor 23, an analog-to-digital conversion unit 24 for the measurement data, and a storage device 25 based on a solid-state integrated circuit.

The device also contains additional sensors. An external pressure sensor 26, an angle rotation sensor 27, and a temperature sensor 28. The information outputs of the odometer 7, the external pressure sensor 26, the angle rotation sensor 27 and the temperature sensor 28 are connected to the corresponding inputs of the analog-to-digital conversion unit 24.

The device comprises a generator 29 and a switch 30. The information outputs 31 of the switch 30 are connected to the information inputs of the analog-to-digital conversion unit 24, and the measurement inputs 32 and 33 of the switch 30 are connected respectively to the terminals of the receiving windings 14.R1-14.RN and 15.R1- 14.RN sensors 14 and 15 of the first and second measuring zone. The output of the generator 29 is connected to the input 34 of the switch 30. The measuring outputs 35 and 36 of the switch 30 are connected respectively to the terminals of the radiating windings 14.T1-14.TN and 15.T1-14.TN of the sensors 14 and 15 of the first and second measuring zone.

The control output of the processor 23 is connected to the control input of the switch 30.

Through the lock chamber, a device — an in-tube projectile — is introduced at the beginning of the monitored section of pipeline 3. Moreover, for the period of monitoring the pipeline 3, the flow of the transported product through it does not stop. The optimal design speed of the in-tube projectile through the pipe is 1 ÷ 3 m / s at a speed of movement of the transported product, such as gas, up to 17 m / s. The speed of movement is provided by the so-called "bypass" system of interaction between the transported product and the in-tube projectile, in which the transported product, flowing around the projectile structure, creates an aerodynamic force that causes the projectile to continuously move in the direction of flow of the transported product.

When the device moves through the pipeline 3, the on-board computer 9, controlling the switch 30, organizes acoustic measurement cycles, alternately including the emitting T and R-receiving windings of each of the N receiving-emitting electromagnetic-acoustic sensors 14 and 15. In this case, the switch 30 first connects the corresponding emitting windings T to the generator 29, and then the corresponding receiving windings R to the block 24 analog-to-digital conversion. The number of simultaneously connected radiating T and receiving R windings and the order of their connection is set by the computer program 9. The measurement data are digitized and recorded in the memory 25 of the on-board computer 9. Simultaneously, signals from other sensors, in particular, the odometer 7, are recorded.

Upon completion of the control of a given section of the pipeline 3, the device is removed from the pipeline 3 and the data accumulated during the diagnostic process are transferred to a stationary computer. Subsequent analysis of the recorded data allows us to conclude that there are defects and to determine their size and location on the pipeline 3.

The device is based on the electromagnetic-acoustic (EMA) method of exciting and receiving ultrasonic vibrations. Between the two magnetizing belts, a longitudinal magnetization region is created due to the yoke, radially magnetized permanent magnets 10 and 11 and brushes 12 and 13 made of soft magnetic material. Brushes 12 and 13 close the magnetic flux from the magnets 10 and 11 to the pipe 3 without an air gap. The closure of the magnetic flux from the magnets to the pipe through flexible magnetically soft brushes 12 and 13 provides the necessary magnitude of the magnetic field in the pipe wall.

The receiving and emitting electromagnetic-acoustic sensors 14 and 15 are arranged in such a way that the axis of the radiation pattern of each of them makes an angle of 45 ° to the magnetization vector N _s (Figs. 4, 6), moreover, the adjacent sensors in each belt are orthogonal to each other. Thus, a structure is created in which the measuring belt contains a series of sensors alternating at an angle of plus 45 ° and minus 45 °. An ultrasonic pulse emitted by the T sensor propagates along the pipe wall and, in the event of a defect 37 on its path, part of the radiation is reflected, part is scattered, and part passes in the same direction. These reflected and direct signals are recorded by receiving R sensors. The device allows you to use the echo location method and the shadow location method.

The measurement cycle is set by the on-board computer 9. The processor 23 of the on-board computer 9 outputs the signals to the switch 30 according to the program located in the storage device 25. First, a control signal is supplied to the switch 30, which connects the generator 29 to, for example, the terminals of the radiating winding 15.2T of the sensor 15.2 As a result, a pulse with high-frequency filling is formed, which excites a sound wave in the pipe wall. Then the generator 29 is turned off and the receiving R windings of the sensors 15 and 14 are connected. As can be seen from Fig. 4, taking into account the receiving radiation pattern, the signals reflected from the defect will be recorded mainly by the windings 15.5R, 14.2R and 15.2R, and the windings passed through the defect 14.5R. Further, information signals through the switch 31 and the analog-to-digital conversion unit 24 are supplied to the storage device 25. Then, a second measurement cycle is carried out, when the generator 31 is connected to the adjacent radiating sensor 15.2T, oriented orthogonally to the previous sensor 15.1T.

Claims (1)

An in-line electromagnetic-acoustic scanner containing a housing (yoke), at the ends of which are locomotor elements, a magnetizing system, made in the form of two magnetizing belts of permanent magnets mounted on the housing, brushes are fixed at the ends of which, permanent magnets in each magnetizing the belts have a radial but opposite magnetization, a measuring system located between the magnetizing belts, containing two electromagnetic-acoustic belts, each the first of which contains receiving and emitting electromagnetic acoustic sensors located evenly around the perimeter, which are pressed with elastic elements to the inner surface of the pipeline, receiving and emitting electromagnetic acoustic sensors are located at an angle of 45 ° to the magnetization vector, and adjacent receiving and emitting electromagnetic the acoustic sensors in each of the measuring zones are orthogonal to each other, and each of the receiving-emitting electromagnetic acoustic sensors is made in the form of a layer APIS on which the planar radiating and receiving coil wound in a meandering manner, wherein the meander shoulder substantially smaller lateral edge which provides a directivity pattern of reception and radiation of signals.