RU2496106C1 - Method of non-destructive x-raying of pipelines and device for its implementation - Google Patents

Abstract

FIELD: test equipment.

SUBSTANCE: positioning and travelling system is rotated around a pipeline, the latter is X-rayed by the X-ray emitter and the radiation detector which are set on diametrally opposite sides of the positioning and travelling system, at that the X-ray emitter is fixed at the angle of not more than 15 degrees in relation to the pipeline surface, and when a defect is found the detector rotation angle is changed in relation to the pipeline surface, the pipeline is X-rayed again up to receiving the 3D image of the defect and basing on the X-raying results the type, form, occurrence depth of the defect are defined.

EFFECT: quality improvement of the examined pipeline image, credibility and accuracy of its control.

10 cl, 2 dwg

Description

The claimed group of inventions relates to the field of research, analysis and control of materials by the radiation method, and can be used to detect, identify and rank defects in objects, in particular pipelines and other cylindrical vessels for transporting gas, liquids such as crude oil, oil products and other chemical substances.

A known method according to GOST 27947 "Non-destructive testing. X-ray television method ”includes transillumination of an object by an x-ray radiation source (hereinafter referred to as the radiation source) and receiving a signal by the radiation receiver, which are located on diametrically opposite sides. From the radiation receiver, the signals are transmitted to a video monitoring device, receive an image of the object, examine the image of the object, identify defects. This method does not guarantee the reliability and accuracy of the control and the device for implementing the known method is cumbersome, it cannot be used in the field.

A mobile X-ray device is known (US Patent No. 7319738, published January 15, 2008, IPC: G01N 23/02, H05G 1/02), designed for non-contact, non-destructive inspection of pipelines, etc., consisting of a lifting mechanism mounted on a movable base . The platform has a sliding rail for moving the C-arm, which is mounted on the mounting device with the possibility of rotation, and is connected with the platform. A scanning system consisting of a radiation source and a radiation receiver located on diametrically opposite sides is fixed on the C-arc. The radiation receiver is connected to the data acquisition and visualization system of the pipeline, which is connected to a computer control system for the positioning mechanism.

The known device has a complex bulky design, and to move the device along the pipeline requires the presence of roads, which is not always possible in the field. In addition, with this type of mounting of the scanning system, the conditions for obtaining clear x-ray images are not ensured, which affects the accuracy of the control of the pipeline, while this device does not automatically mark the location of the detected defects on the pipeline.

Closest to the claimed method is the "Method of automated, digital, radiographic inspection of the pipeline" (US Patent No. 7656997, published September 15, 2008, IPC: G01N 23/02), selected as a prototype.

The known method includes rotating the positioning system and moving around the pipeline, translucent the pipeline with a radiation source and receiving a signal from the radiation receiver, which are located on the positioning and moving system on diametrically opposite sides. At the same time, signals from the radiation receiver are received to the control panel, which makes it possible to obtain an image of the pipeline and examine the detected defects on a computer. After completing a complete revolution of the positioning system and moving around the pipeline, the positioning and moving system performs a longitudinal movement along the pipeline. The above steps are repeated many times until the completion of the pipeline study.

Closest to the claimed device is a "Device for automated, digital, radiographic inspection of the pipeline" (US Patent No. 7656997, published September 15, 2008, IPC: G01N 23/02), selected as a prototype.

The known device contains a radiation source, a radiation receiver, a positioning and moving system on which a radiation source and a radiation receiver are mounted on diametrically opposite sides, rotatably concentric with respect to the pipeline, a control panel connected to the radiation receiver, and providing an image of the pipeline and investigation of detected defects on the computer.

A disadvantage of the known method and device according to US patent No. 7656997, is that they do not provide:

- sufficient image quality of the studied pipeline, due to the overlapping image of the weld or the main metal of the pipeline from the side of the radiation source to the resulting x-ray, as the radiation source and radiation receiver are fixed parallel to each other and the surface of the pipeline;

- the reliability and accuracy of the control of the pipeline, due to the rigid positioning of the radiation receiver relative to the controlled pipeline, which does not allow changing the angle of rotation of the radiation receiver relative to the pipeline;

- scanning the pipeline in a spiral. This is due to the fact that in the known method and device, after completion of movement around the circumference, the positioning and moving system makes a longitudinal movement, which excludes the possibility of movement of the positioning system and moving in a spiral.

The main objective of the claimed group of inventions is to create a method of non-destructive x-ray inspection of pipelines and devices for its implementation, providing flaw detection of pipelines and allowing to obtain a high-quality image of the studied pipeline, to automatically identify and rank the detected defects and anomalies in the obtained radiographs, including determining the depth of defects.

The technical result consists in improving the image quality of the studied pipeline, the reliability and accuracy of the control, by attaching the radiation source at an angle of no more than 15 degrees to the pipeline, to prevent overlapping images of the weld or defects of the main metal of the pipeline from the side of the radiation source on the resulting x-ray and provide multi-angle transillumination of the pipeline by changing the angle of rotation of the radiation receiver, and the implementation of synchronous radial and longitudinal displacements positioning system and movable relative to the pipeline, the pipeline control which provides a spiral. An additional increase in the accuracy of control is provided due to the automatic marking of defects directly on the studied pipeline.

The problem is solved in that in the claimed method of non-destructive x-ray inspection of pipelines, based on the rotation of the positioning system and movement around the pipeline, its transmission using installed on the diametrically opposite sides of the positioning system and the movement of the radiation source and radiation receiver. The radiation source is fixed at an angle of no more than 15 degrees relative to the surface of the pipeline, and in case of detection of a defect, the angle of rotation of the radiation receiver is changed, relative to the surface of the pipeline, the pipeline is re-illuminated until a volumetric image of the defect is obtained, and the type, shape and depth defect.

It is optimal to change the angle of rotation of the radiation receiver relative to the surface of the pipeline in the range from 0 to 25 degrees.

To scan the pipeline in a spiral, it is advisable to synchronously radially and longitudinally move the positioning system and move relative to the pipeline.

The problem is also solved by the fact that in the inventive device for non-destructive x-ray inspection of pipelines containing a control and registration unit, a positioning and moving system that is installed coaxially to the object of control, covering the object, radiation source and radiation receiver mounted on diametrically opposite sides of the positioning system and moving. The radiation source is fixed at an angle of no more than 15 degrees relative to the surface of the pipeline in order to avoid overlapping images of the weld or main metal of the pipeline from the side of the radiation source to the resulting x-ray and into the positioning and displacement system, a rotation angle change mechanism is connected to the radiation receiver.

It is preferable to additionally equip the device with a flaw detector located inside the positioning and moving system, made in the form of a controlled spray gun.

Optionally perform a closed loop positioning and movement system. In this case, the lower part of the positioning and moving system can be equipped with an insert plate, with the help of which a closed loop of the positioning and moving system is created, which provides a more uniform rotation of the positioning and moving system around the object.

The positioning and moving system can be performed open.

It is advisable to perform the control and registration unit in the form of a computer connected to a monitor and a control panel.

The technical result of the proposed method is achieved by establishing on the positioning system and moving the radiation source at an angle of not more than 15 degrees relative to the surface of the pipeline and multi-angle transmission of the pipeline, provided by changing the angle of rotation of the radiation receiver. Moreover, the claimed result is also achieved using a device in which, to improve the image quality, for automatic identification and ranking of detected defects and anomalies in the obtained X-ray diffraction patterns, including determining the depth of defects, the radiation source is mounted on the positioning and movement system at an angle of no more than 15 degrees relative to the surface of the pipeline, and a mechanism for changing the angle of rotation connected to the radiation receiver is introduced into the positioning and moving system . Maintaining multi-angle transmission of the welds and the base metal of the pipeline by exposing the pipeline, followed by the automatic formation, processing and visualization of the reconstructed x-ray image from two projections, makes it possible to increase the reliability and accuracy of non-destructive x-ray inspection.

Additional control accuracy is ensured by automatic marking of defects in the pipeline directly during the monitoring process by introducing a flaw detector located inside the movement and positioning system, as well as synchronous movement of the movement and positioning system, providing longitudinal and radial control of the pipeline in a spiral.

Automatic identification and ranking of detected defects and anomalies in the obtained X-ray diffraction patterns, including determination of the depth of defects, is carried out using a specialized program.

The drawings schematically represent an image of the claimed device.

Figure 1 is a top view.

Figure 2 is a front view.

A device for non-destructive x-ray inspection of pipelines, designed to implement a method of non-destructive x-ray inspection, contains a positioning and movement system 3, designed for radial and longitudinal movement around the pipe 4, which is installed coaxially to the pipe 4, covering it, while on diametrically opposite sides of the positioning system and displacements 3 a radiation source 1 and a radiation receiver 2 are installed. The radiation source is fixed at an angle of not more than 15 g Adeus relative to the surface of the pipeline, a rotation angle change mechanism 7 is connected to the radiation positioning system 7, connected to the radiation receiver 2, and a flaw detector 8, which is located inside the positioning and movement system 3. The movement and positioning system 3 contains sensors (not shown in the drawings) monitoring the radial and longitudinal movement of the movement and positioning system 3, which allows the operator to timely eliminate the bias of the movement and positioning system 3 on the pipeline 4 p and its longitudinal movement. Information from sensors (not shown in the drawings) of the positioning and moving system 3 and radiation receiver 2 is transmitted to the control and registration unit 5, located at a safe distance from the influence of x-ray radiation - at least 25 meters from the monitored pipeline 4. Device for non-destructive x-ray Pipeline control has an autonomous power supply 6. For more uniform rotation of the positioning system and moving 3 around the pipeline 4, the lower part of the positioning system and moving 3 Ia may be provided with an insert plate-9 (Figure 2), by means of which creates a closed loop positioning system and the movement 3.

The non-destructive X-ray inspection of pipelines is based on converting the energy of X-rays transmitted through the pipe 4 into a visible image, followed by capturing the image of the pipe 4, transmitting the signal via a communication channel to the control and recording unit 5 and displaying the received information on the monitor screen (in the drawings not shown) with subsequent processing in a computer (not shown in the drawings) included in the control and registration unit 5.

The inventive method is implemented through the inventive device as follows.

The positioning and moving system 3 is installed on the pipeline 4. The operator sends a command from the control and registration unit 5 to the radiation source 1, fixed at an angle of no more than 15 degrees relative to the surface of the pipeline. The radiation source 1 forms a x-ray beam collimated to the size of the region of the recording part of the radiation receiver 2. The radiation beam passing through the pipe 4 creates a signal on the radiation receiver 2 that corresponds to the x-ray image, while the positioning and moving system 3 provides uniform movement in the longitudinal and / or radial direction, forming a continuous image of the weld or the main metal of the pipe on the monitor ( not shown in the drawings). During radial scanning, the positioning and moving system 3 rotates the radiation source and radiation receiver 360 degrees around the pipeline 4, after which the positioning and moving system 3 moves longitudinally along the pipeline, and the pipeline is also scanned. The operator, upon detection of defects and the need to more accurately determine the characteristics of defects, by applying a signal to the mechanism for changing the rotation angle 7, changes the rotation angle of the radiation receiver 2 from 0 to 25 degrees, for example, to the left to the surface of the pipeline 4 being scanned (Fig. 1). Rescanning is in progress. Then the operator changes the angle of rotation of the radiation detector 2 from 0 to 25 degrees, for example, to the right to the scanned surface of the pipe 4 and gives a signal for the movement of the positioning system and move 3 in the opposite direction. Upon completion of the scan, two images of the same section of the pipeline 4 taken at different angles are obtained. Two projections are used to restore the X-ray image of the pipeline section, as a result of which, on the monitor screen (not shown in the drawings) of the control and registration unit 5, the reconstructed X-ray image of the weld or the base metal of the pipe 4 is visualized, which allows not only to identify and determine the type of defects and their linear dimensions in one plane, but also determine their geometric shape and dimensions in the volume, as well as the depth of their occurrence in the internal volume of the base metal or welded of seam pipe 4. Directly during scanning, using specialized software automatically analyzes the control results provides registration, identification and depth of defects is determined and noted the presence of a defect on the radiograph. Next, the system of movement and positioning 3 performs longitudinal movement along the pipeline 4 and the scanning steps are repeated. If the system of movement and positioning 3 performs synchronous longitudinal and radial movement by synchronized movement of the longitudinal and radial motion drives (not shown in the drawings), then the studied pipeline is scanned in a spiral. During spiral movement, the spiral pitch is set and the device moves one revolution in a spiral, and if it is necessary to more accurately determine the characteristics of defects, the operator starts the device in a spiral direction in the opposite direction, and then the device automatically moves in the longitudinal direction to the point of the beginning of the reverse spiral movement.

Flaw detector 8, located inside the positioning and moving system 3, which is, for example, a controlled spray gun, when a defect is detected, receives a signal to mark the defective area, which is supplied by the operator from the control and registration unit 5 at the time of detection of the defect.

A device for non-destructive x-ray inspection of pipelines provides the ability to diagnose pipelines with a diameter of 500 mm to 1400 mm. The movement and positioning system 3 is interchangeable.

The equipment for the positioning and moving system is fastened with quick-disconnect couplings, for example, couplings. Reinstalling the positioning and moving system 3 to a different diameter of the pipeline 4 takes about 20 minutes.

The movement and operation of the positioning and movement system 3 is set by a special program. The control results are systematized and stored in a computer and other electronic information carriers, which allows you to visualize and print images of the area of the defect or anomalies in the pipeline.

The inventive method was implemented using a device for non-destructive x-ray inspection of pipelines, consisting of:

- a radiation source 1, which is used as the radiation source of a monoblock device, for example, RAP 220-5 company "Photon";

- radiation detector 2, which was developed specifically for the inventive device based on semiconductor detectors and single crystals, and is a discrete-linear detector that provides high dose and defectoscopic sensitivity due to geometric and density characteristics, signal amplification and noise suppression, with a sensitivity not more than 2% for steel up to 40 mm thick, which corresponds to sensitivity class 1 for welded joints according to GOST 7512-82;

- positioning and moving system 3, which uses radial and longitudinal movement drives, consisting of motors, control controllers and mechanical gears (not shown in the drawings), which allows for accurate positioning and movement of radiation source 1 and radiation receiver 2 when monitoring pipe 4 ;

- an autonomous power supply 6, designed to power a device for non-destructive x-ray inspection of pipelines in the field, for example, a power source of the ESE 706 HS / A-GT ES type from ENDRESS (Germany) was selected;

- control and registration unit 5, which was composed of a computer containing a specialized software product, a monitor and a control panel (not shown in the drawings).

A device for non-destructive x-ray inspection of pipelines allows for diagnostic scanning of the surface of pipelines and processing of the received information at high speed. So, as a result of the experiments, the time of a full revolution around the pipeline with obtaining and complete processing of the image of a weld of 3 m in length was no more than 180 seconds. The maximum pipe wall thickness is determined by the power of the radiation source and the sensitivity of the radiation receiver.

The device for non-destructive X-ray inspection of pipelines is compact with a minimum weight (for example, a positioning and moving system can be installed manually on an object with two people), therefore, lifting and transport mechanisms are not required when loading, unloading, assembling and disassembling. Installation and dismantling of the device takes no more than 20 minutes.

The claimed group of inventions provides for fixing the radiation source at an angle of no more than 15 degrees relative to the surface of the pipeline in the positioning and moving system and multiple viewing of the object by changing the angle of rotation of the radiation receiver, which improves the quality of control, namely, ensuring a higher image quality of the investigated weld and / or the main metal of the pipeline, automatic identification and ranking of identified defects and anomalies in the rent genograms, including determining the depth of defects.

Thus, the use of the claimed method of non-destructive x-ray inspection of pipelines and a device for its implementation can improve the reliability and quality of control of the studied pipeline, which leads to operational reliability of pipelines.

Claims (10)

1. The method of non-destructive x-ray inspection of pipelines, based on the rotation of the positioning system and movement around the pipelines, its transmission using installed on diametrically opposite sides of the positioning and movement of the x-ray radiation source and radiation receiver, characterized in that the x-ray radiation source is installed at an angle not more than 15 degrees relative to the surface of the pipeline and when a defect is detected, the angle of rotation of radiation source relative to the surface of the pipeline, the pipeline is re-illuminated until a volumetric image of the defect is obtained and the type, shape and depth of the defect are determined by the results of the translucency. 2. The method according to claim 1, characterized in that the radiation receiver is rotated relative to the surface of the pipeline by an angle in the range from 0 to 25 degrees. 3. The method according to claim 1, characterized in that produce synchronous radial and longitudinal movement of the positioning system and the movement relative to the pipeline. 4. A device for non-destructive x-ray inspection of pipelines, comprising a control and registration unit, a positioning and moving system that is installed coaxially to the pipeline, encompassing a pipeline, an x-ray radiation source and a radiation receiver mounted on diametrically opposite sides of the positioning and moving system, characterized in that the radiation source is fixed at an angle of no more than 15 degrees relative to the surface of the pipeline, and into the positioning and moving system ene mechanism for changing the angle of rotation, connected to the radiation receiver. 5. The device according to claim 4, characterized in that it is additionally equipped with a flaw detector located inside the positioning and moving system. 6. The device according to claim 4, characterized in that the flaw detector is made in the form of a controlled spray gun. 7. The device according to claim 4, characterized in that the positioning and movement system is closed. 8. The device according to claim 7, characterized in that the lower part of the positioning and movement system is equipped with an insert plate. 9. The device according to claim 4, characterized in that the positioning and movement system is made open. 10. The device according to claim 4, characterized in that the control and registration unit is made in the form of a computer connected to a monitor and a control panel.

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