阅读说明：本技术 一种用于管道内缺陷巡检的x射线背散射检测装置 (X-ray backscatter detection device for inspecting defects in pipeline ) 是由 李会 李德源 张小东 于 2020-06-22 设计创作，主要内容包括：本发明涉及一种用于管道内缺陷巡检的X射线背散射检测装置,所述装置被定位于管道中心,在管道内部采用螺旋前进的方式进行扫描；所述装置包括X射线背散射检测扫描头,控制与冷却装置,电源与驱动装置；所述X射线背散射检测扫描头包括主轴；扫描头主轴上设有射线源室；所述射线源室,用于放置放射源；所述射线源,用于产生能够为成像提供足够穿透力的射线；所述射线背散射检测扫描头还包括可绕扫描主轴旋转的射线束准直器,用于将离开所述源室的射线调制成多个笔形射线束；以及多组可绕扫描主轴旋转的探测器,用于探测被管壁背向散射的X射线。本发明的用于管道内缺陷巡检的X射线背散射检测装置能够实现各类缺陷的全面检测,且可在恶劣环境及源和探测器需要单侧布置的检测任务中使用。(The invention relates to an X-ray back scattering detection device for inspecting defects in a pipeline, which is positioned in the center of the pipeline and scans the interior of the pipeline in a spiral advancing mode; the device comprises an X-ray back scattering detection scanning head, a control and cooling device, a power supply and a driving device; the X-ray backscatter detection scanning head comprises a main shaft; a ray source chamber is arranged on the main shaft of the scanning head; the ray source chamber is used for placing a radioactive source; the ray source is used for generating rays capable of providing enough penetrating power for imaging; the ray backscatter detection scanning head further comprises a ray beam collimator capable of rotating around a scanning main shaft and used for modulating rays leaving the source chamber into a plurality of pencil-shaped ray beams; and a plurality of sets of detectors rotatable about the scanning main axis for detecting X-rays backscattered by the vessel wall. The X-ray back scattering detection device for inspecting the defects in the pipeline can realize comprehensive detection of various defects and can be used in severe environments and detection tasks in which sources and detectors need to be arranged on one side.)

1. An X-ray back scattering detection device for inspecting defects in a pipeline is characterized in that,

the device is positioned in the center of the pipeline, and the inside of the pipeline is scanned in a spiral advancing mode;

the device comprises a ray back scattering detection scanning head, a control and cooling device, a power supply and a driving device;

the ray backscatter detection scanning head comprises a main shaft; a ray source chamber is arranged on the main shaft;

the ray source chamber is used for placing a radioactive source;

the ray source is used for generating rays capable of providing enough penetrating power for imaging;

the ray backscatter detection scanning head also comprises a ray beam collimator which can rotate around a scanning main shaft and is used for modulating rays leaving the source chamber into a pencil-shaped ray beam; and

and a plurality of groups of detectors which can rotate around the scanning main shaft and are used for detecting the rays backscattered by the tube wall.

2. An X-ray backscatter detection apparatus for in-pipeline defect inspection according to claim 1, wherein the X-ray backscatter detection scanning head further comprises a rotating bracket for fixing and supporting the detector and the beam collimator and driving the beam collimator and the detector to rotate.

3. An X-ray backscatter detection device for in-tunnel defect inspection according to claim 2, wherein the rotatable beam collimator is circumferentially disposed outside the source chamber and modulates the radiation leaving the source chamber into a pencil beam; the pencil-shaped ray beams are emitted along the radial direction of the pipeline and are vertical to the wall of the pipeline; the rotatable detectors are arranged on two sides of the collimator in pairs along the axial direction of the pipeline; the pencil beam is positioned at the geometric center of the rotatable detector pair arrangement, and the number of the detector pairs is consistent with that of the pencil beams.

4. An X-ray backscatter inspection device for in-pipe defect inspection according to any one of claims 1 to 3, wherein the device further comprises in-pipe centering defining means for centering the inspection device in the pipe.

5. An X-ray backscatter detection apparatus for in-pipe defect inspection according to any one of claims 1 to 3, wherein the scanning spindle further comprises a fairing provided at a forward end thereof.

6. An X-ray backscatter detection device for in-pipe defect inspection according to any one of claims 1 to 3, wherein the radiation backscatter detection scanning head, the control and cooling device, and the power supply and drive device are connected by a hinge device.

7. An X-ray back scattering detection device for inspecting defects in pipelines according to claim 2, wherein the rotary support is cylindrical and covers the outer part of the main shaft; the rotating bracket is connected with the scanning main shaft through a bearing; the inner wall of the rotating bracket is fastened with a plurality of permanent magnets which are uniformly distributed; a plurality of armature cores are distributed on the scanning main shaft, and armature windings are wound on the armature cores.

8. An X-ray backscatter detection device for in-pipeline defect inspection according to claim 1, wherein the in-pipeline centering limiting device comprises a hinge, a slider connector, a universal wheel and a telescopic rod, and the telescopic rod is adjusted to enable the detection device to be suitable for pipe wall defect detection of pipelines with different inner diameters according to the inner diameter of the pipeline to be detected.

9. The X-ray backscatter detection device for in-pipeline defect inspection as recited in claim 1 or 8, wherein the ray is an X-ray, the X-ray tube uses a peripheral machine, generates 360 ° circumferentially emitted X-rays, and forms a circumferentially distributed pencil X-ray beam through a rotatable collimator; the anode target of the X-ray tube is conical, and the X-ray tube is positioned in the center of the pipeline.

Technical Field

The invention relates to the technical field of nuclear radiation backscatter imaging devices, in particular to an X-ray backscatter detection device for inspecting defects in a pipeline.

Background

The problems facing pipeline operators in managing the integrity of their production wells and pipeline assets are pipeline fouling, corrosion, deposits, and pipeline and casing defects, among others. These defects typically result in a reduction in the production capacity of the production well by about 5% to 20%, and potentially catastrophic failure, possibly leading to serious injury or even death. Thus, expensive repairs (repairs or replacements) of casing integrity problems are required.

Due to the technical limitations of pipeline overhaul operating conditions and existing inspection techniques, conventional mineral scale formation, microbial induced corrosion, and material defect assessment and inspection processes in wellbores and pipelines are very complex, time consuming, and costly. The common ultrasonic in-tube detection mode can detect the layered corrosion and the wall thickness, but has poor detection effect on the point corrosion, and needs a liquid medium and a cleaning device; the magnetic flux leakage detection mode can detect point corrosion and deformation, but the detection effect of micro-size corrosion damage is not good. And the detection results of the two detection means are displayed by curves, so that the requirement on professional knowledge storage of detection technicians is high. In addition, the detector of the detection device is used more, and the maintenance cost is higher.

The detection device based on the Compton scattering imaging technology has the advantages that the radiation source and the imaging device are placed on the same side of the target object, the given inspection result can be displayed through visual images, and the detection device has the advantages when being applied to defect inspection in a pipeline. Compton scatter images are formed by spot scanning of a pencil X-ray beam over an object under examination. At each position scanned by the pencil X-ray beam, scattered X-rays are collected by a detector located on the same side of the system as the X-ray source. By tracking the instantaneous position of the pencil X-ray beam on the target object and measuring the overall intensity of scattered X-rays incident on the detector, scattered ray intensity can be correlated to each pencil X-ray beam scanning position on the target detection object. The object may then be moved or the X-ray backscatter detector arrangement may be moved by moving the target object in a direction perpendicular to the scanning direction of the pencil beam. This allows the target object to be scanned line by line to construct an entire two-dimensional image. And by combining with machine vision related research, the automatic identification of artificial intelligence images can be realized.

X-ray backscatter imaging is currently used to detect and screen various objects, such as luggage, vehicles, and people. The working environment for detecting and screening these objects by conventional X-ray backscatter imaging devices is relatively clean and at ambient temperature and pressure. However, the environment inside the well casing is not clean, typically at high temperatures and pressures, and conventional X-ray backscatter imaging devices cannot withstand such conditions. Furthermore, the geometry of the wellbore casing and tubing is cylindrical and is not in the scope of conventional applications. To solve this problem, there is a need for an X-ray backscatter imaging device that can be used for inspection of defects in pipelines.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide an X-ray backscatter detection device for inspecting the defects in the pipeline, which can be used in severe environments and complex pipeline structures, can perform online detection on the defects in the pipeline under the condition of not influencing the medium transported by the pipeline, and can practice full-automatic detection by combining an artificial intelligence defect identification technology.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

an X-ray back scattering detection device for inspecting defects in a pipeline is positioned in the center of the pipeline, and the inside of the pipeline is scanned in a spiral advancing mode;

the device comprises a ray back scattering detection scanning head, a control and cooling device, a power supply and a driving device;

the ray backscatter detection scanning head comprises a scanning main shaft; a ray source chamber is arranged on the scanning main shaft;

the ray source chamber is used for placing a radioactive source;

the ray source is used for generating rays capable of providing enough penetrating power for imaging;

the ray backscatter detection scanning head also comprises a plurality of ray beam collimators capable of rotating around a scanning main shaft and used for modulating rays leaving the source chamber into pencil-shaped ray beams; and

a plurality of groups of detectors which can rotate around the scanning main shaft and are used for detecting rays backscattered by the tube wall;

furthermore, the ray backscatter detection scanning head further comprises a rotating bracket which is used for fixing and supporting the detector and the ray beam collimator and driving the ray beam collimator and the detector to rotate.

Further, the rotatable beam collimator is circumferentially arranged outside the source chamber, and modulates the radiation leaving the source chamber into a pencil beam; the pencil ray beams are emitted along the radial direction of the pipeline and are vertical to the wall of the pipeline. The rotatable detectors are arranged on two sides of the collimator in pairs along the axial direction of the pipeline; the pencil-shaped ray beams are positioned at the geometric center of the arrangement of the rotatable detector pairs, and the number of the detector pairs is consistent with that of the pencil-shaped ray beams;

further, the device also comprises an inner pipe centering limiting device used for positioning the detection device at the center of the pipe.

Further, the scanning main shaft also comprises a fairing arranged at the front end of the scanning main shaft.

Furthermore, the ray back scattering detection scanning head, the control and cooling device and the power supply are connected with the driving device through a hinge device.

Further, the rotating bracket is cylindrical and is covered outside the main shaft; the rotating bracket is connected with the scanning main shaft through a bearing; the inner wall of the rotating bracket is fastened with a plurality of permanent magnets which are uniformly distributed; a plurality of armature cores are distributed on the scanning main shaft, and armature windings are wound on the armature cores.

Further, limiting device placed in the middle in the pipeline includes articulated elements, slider connecting piece, universal wheel and telescopic link, according to the internal diameter of waiting to detect the pipeline, adjusts the telescopic link and can make detection device can be applicable to the pipeline pipe wall defect detection of different internal diameters.

Further, the ray is an X ray, the X ray tube adopts a peripheral machine, the X ray tube generates 360-degree peripheral emission X rays, and a circumferentially distributed pencil X ray beam is formed through the rotatable collimator. The anode target of the X-ray tube is conical, and the X-ray tube is positioned in the center of the pipeline.

Compared with the prior art, the invention has the following beneficial effects:

1. the pipe wall defect detection device is designed based on the Compton scattering imaging technology, has the advantage that a radiation source and an imaging device are both arranged on the same side of a detection object, can display a given detection result in a visual image, realizes comprehensive detection of various defects, and can operate under extreme conditions of a well casing, an oil pipeline and the like.

2. The device can be used in harsh environments such as well casings, oil pipelines and the like, and can also be used in other structures with similar geometric factors. For example, the device may be used in water and gas pipelines, in commercial chimneys for power plants, and in large storage vessels to inspect walls or linings. The device can also help in the detection of components of dams, bridges and buildings.

Drawings

FIG. 1 is a schematic diagram of the overall concept of an X-ray backscatter detection device for in-pipe defect inspection according to the present invention;

FIG. 2 is a schematic view of two detector arrangements of a backscatter detection scan head of the present invention;

FIG. 3 is a cross-sectional schematic view of an X-ray backscatter scan head of an embodiment of the invention;

in the figure: 101-a pipeline; 102-backscatter detection scan head; 103-a hinge arrangement; 104-control and cooling means; 105-power supply and drive means; 201-pencil beam; 202-a rotatable detector; 203-a rotatable collimator; 204-rotating the support; 205-source chamber of rays; 301-scanning spindle; 302-a fairing; 303-anode target; 304-a cathode filament; 305-a hinge; 306-a slider connection; 307-universal wheels; 308-a telescopic rod; 309-armature winding; 310-armature core; 311-a permanent magnet; 312-bearing.

Detailed Description

The embodiment provides a design scheme of the in-pipeline defect inspection device adopting an X-ray back scattering imaging technology for solving the problems that the defect inspection type is not comprehensive and the detection result is not visual in the existing in-pipeline defect inspection device, the in-pipeline defect inspection device applying the scheme can perform online defect detection on high-temperature, high-pressure and other severe environments and pipelines with complex geometric structures, and can detect various defects and display detection structures by visual images.

An X-ray backscatter detection device according to an embodiment of the present invention will be described below with reference to the drawings. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the disclosure to the particular form, but rather to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims. The figures are not drawn to scale for purposes of illustration.

FIG. 1 is a schematic diagram showing the overall concept of an X-ray backscatter detection device for in-pipeline defect inspection according to the present invention; the device scans in the pipeline 101 in a spiral advancing mode to obtain scanning data in the pipeline, and transmits the scanning data to a display end to display in an image form. The defects in the image can be detected by using artificial intelligence so as to reduce the workload of detection personnel and improve the detection efficiency. The device consists of an X-ray backscatter detection scanning head 102, a control and cooling device 104, a power supply and drive device 105 and a flexible hinge device 103. Among them, the X-ray backscatter detecting scan head 102 will be described in detail in fig. 2 and 3. Flexible hinge assembly 103 connects the various components to allow the assembly to move as a hinge in a pipe bend or bifurcation as well. The control and cooling device 104 is equivalent to the brain of the whole device, controls the data transmitted from the scanning head, and transmits the data to the external host computer in a wireless or wired mode for display; 104 is also responsible for receiving and processing user instructions, sending warnings and error messages, etc., controlling the operation of the overall machine, and providing cooling services to the overall device. The power and drive device 105 provides power and power drive for the entire device. Due to the space limitation in the conduit, the respective devices may be individually arranged by using the hinge structure, and are not particularly limited to this example.

To generate a continuous target image, a continuous data stream needs to be obtained; the X-ray source must produce a continuous or high duty cycle fan beam. The opening angle of the fan beam should also be large in order to obtain a reasonable covered field of view. In order to enable pixel-by-pixel scanning of the pencil beam on the target, a rotatable collimator is located in front of the fan beam and has an opening designed to allow passage of a pencil beam of the required size. As the collimator rotates, it selects different parts of the X-ray fan beam so that the pencil beam scans in one dimension across the object. A rotating collimator is typically used to provide this function rather than a reciprocating collimator. The resolution of the system is determined by the aperture of the chopper wheel, the size of the focus of the X-ray tube and the distance from the chopper wheel to an object to be detected. Detectors intended to collect backscattered radiation do not affect the image resolution.

Fig. 2 is a schematic diagram of two detector arrangements for a backscatter detection scan head of the present invention. The detector module of the device consists of a pencil-shaped collimated ray beam 201, a rotatable detector 202, a rotatable collimator 203 for forming the pencil-shaped collimated ray beam, a detector and collimator support 204 and a ray source room 205. The radiation may be any radiation that can provide sufficient penetration for imaging, and X-rays, gamma rays, neutrons, terahertz, electrons, or the like may be used. The X-ray tube is located in the radiation source chamber. The X-ray tube adopts a peripheral machine, generates X-rays emitted in the peripheral direction of 360 degrees, and forms a circumferentially distributed pencil X-ray beam through the rotatable collimator 203; the X-ray beam is compton scattered from interaction with the material of the pipe 101 and the scattered radiation is detected by the rotatable detector 202. The rotatable collimator and the rotatable detector are mounted on the collimator mount 204 and are driven to rotationally scan the inner wall of the tube, the scan data forming a scan image. Since the pencil beam needs to move rotationally with the detector, the detector needs to be arranged in pairs with the beam; the number of scanning beams and detector arrangements cannot be too large due to space constraints within the tube and economic cost considerations for the apparatus. Figures 2(a) and 2(b) show the arrangement of the detection system in the scanning head with two and three pencil beams respectively. Fig. 2(a) employs two pencil beams, two pairs of semi-cylindrical detectors, arranged axially on either side of the pencil beam, the pencil beam being centered in the geometric arrangement of the detector pairs. The detectors are separated by the detector support, so that the back scattering rays can be prevented from being interfered between the detectors, and in addition, the energy threshold value of the detectors can be set, and the signal to noise ratio is improved by deducting the multiple scattering low-energy particles. Fig. 2(b) uses three pencil beams, three pairs of flat detectors, again arranged axially on either side of the pencil beam, the pencil beam being located at the centre of the geometrical arrangement of the detector pairs. The number of pencil beams and detectors is increased, which is beneficial to improving the scanning speed of the device; the detector shape and detector arrangement are not limited to the forms shown by the examples.

Fig. 3 is a schematic cross-sectional view of an X-ray backscatter scanning head according to an embodiment of the invention, showing details of the scanning head of the X-ray backscatter detection device. The main shaft 301 of the device comprises a ray source chamber 205 and a fairing 302. The radiation source chamber 205 houses a radiation source, in this example an X-ray tube, consisting of an anode target 303 and a cathode filament 304; to form 360 ° circumferentially emitted X-rays, the anode target 303 needs to adopt a conical structure; because the device is used in a pipeline, which is often used to transport fluids, the fairing 301 can be used to reduce the resistance to forward movement of the device. The X-ray back scattering detection device requires the device to be positioned in the center of a pipeline during operation, and a centering limiting device is adopted. The centering limiter consists of a hinge 305, a slider link 306, a universal wheel 307 and a telescoping rod 308. The telescopic rod 308 is driven by a built-in hydraulic mechanism to extend and contract, and pushes the sliding block 306 to move, so that the centering limiting device is adjusted to be suitable for pipelines with different inner diameters. The rotatable collimator 203 and the rotatable detector 202 are both fixed on the detector and collimator support 204; the detector and collimator mount 204 is coupled to the device main shaft 301 by bearings 312. The inner wall of the rotating drum of the detector and collimator support 204 is fastened with a plurality of permanent magnets 311 which are uniformly distributed. The permanent magnet 311, the armature core 310 and the armature winding 309 form a motor, which drives the X-ray back scattering device to rotate to scan the pipeline. A plurality of armature cores 310 are uniformly distributed on the main shaft 301; armature windings 309 are wound around armature core 310 and the device can be driven in rotation by passing alternating current through armature windings 310.

According to an embodiment of the present invention, the X-ray backscatter scanning head 102, the cooling and control device 104, and the power supply and driving device form an X-ray backscatter detection device. Without departing from the basic concept of this patent, a set of X-ray backscatter detection apparatus may be employed to configure a plurality of X-ray backscatter scanning heads 102 or a plurality of cooling and control devices, etc. The device is powered by a battery to provide drive or driven to advance in the pipeline by the pressure difference generated by fluid in the pipeline before and after the device. The X-ray tube and high voltage electronics are cooled by a closed loop water cooling system. The cooling system releases heat generated by the device into the fluid transported by the conduit. For gaseous fluids, a water-to-air heat sink may be used; for the liquid may be a water-to-liquid heat sink.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such modifications and variations.