A method for positioning optical cables along a pipeline

Abstract

This invention discloses a method for locating optical fiber cables coiled along a pipeline. The method includes: connecting an optical fiber vibration detection device to the optical fiber cable under test and sending a pipeline pig inside the pipeline, causing the pig to vibrate within the pipeline and transmit the vibration to the optical fiber cable under test; the optical fiber vibration detection device detecting the vibration signal of the optical fiber cable under test; acquiring a first heat map generated by the optical fiber vibration detection device; wherein the first heat map is a graph showing the relationship between the occurrence time and location of the vibration signal; determining the distance segment where the cable coiled along the pipeline is located based on the first heat map; and determining the actual location of the cable coiled along the pipeline based on the distance segment where the cable coiled along the pipeline is located. This invention solves the problem of locating optical fiber cables coiled along a pipeline in trenchless installations, filling a gap in the field; it can quickly locate the ground position of the optical fiber cables coiled along the pipeline, facilitating rapid emergency repair and maintenance of the optical fiber cables.

Description

Technical Field

[0001] This invention relates to the field of optical cable technology, and in particular to a method for positioning optical cables coiled along a duct. Background Technology

[0002] Optical cables accompanying buried pipelines play a vital role in pipeline automation control and data transmission, and the maintenance of communication optical cables is also crucial for the daily operation of pipelines.

[0003] The fiber optic cable accompanying buried pipelines is laid in sections during construction and then spliced ​​together. At each splice point, a cable junction box is installed, and a certain length of cable is coiled. Later, when the cable is broken and re-spliced, junction boxes and cable coiling are also required. However, due to issues such as non-standard construction practices, missing construction records, and lack of electronic identification, the buried location of the cable coils cannot be found on the surface, causing numerous problems and inconveniences for later operation, maintenance, and cable use. Traditional electromagnetic induction methods require excavating the cable, or even breaking it, for cable coiling and location, wasting significant manpower, resources, and time, and causing damage to the cable and increased communication loss. Therefore, accurately determining the ground location of the cable coils along the buried pipeline is of great importance. Summary of the Invention

[0004] This invention provides a method for locating optical cables along pipelines, which solves the problem that existing cable positioning methods require excavation, which can easily damage the optical cables and waste resources.

[0005] A method for locating a duct-accompanying optical cable coil along a pipeline, provided by the present invention, includes: The optical cable vibration detection device is connected to the optical cable under test and a pig is sent into the pipeline so that the pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test. Obtain the first heat map generated by the optical cable vibration detection device; wherein, the first heat map is a graph showing the relationship between the occurrence time and the occurrence location of the vibration signal; The distance segment where the cable coils are located along the line is determined based on the first heat map; The actual location of the cable reels along the route is determined based on the distance segment where the cable reels are located.

[0006] Optionally, the distance segment where the cable coils are located along the line is determined based on the first heat map, including: Obtain the detection mileage segment from the first heat map; wherein, the detection distance segment is the distance segment where the occurrence time of the vibration signal is fixed and the occurrence position changes; The detection mileage section is taken as the distance section where the cable is located along the line.

[0007] Optionally, the actual location of the cable reels along the route can be determined based on the distance segment where the cable reels are located, including: Impressive signals were applied to the sections of cable reel along the route. Obtain the second heat map generated by the optical cable vibration detection device; wherein, the second heat map is a graph showing the relationship between the occurrence time and the occurrence location of the impact vibration signal; The actual location of the cable coils along the route is determined based on the second heat map.

[0008] Optionally, the actual location of the cable coils along the route can be determined based on the second heat map, including: Obtain the detection position in the second heat map; wherein, the detection position is the position corresponding to the fixed occurrence time of the impact vibration signal; The detection location is taken as the actual location of the cable coils along the line.

[0009] Optionally, impact vibration signals are applied to the sections of cable reel along the route, including: Calculate the actual distance segment based on the distance segment where the cable coils are located along the line; Impact vibration signals were applied to the actual distance segments respectively.

[0010] Optionally, the distance segment Lx where the cable is located along the line and the actual distance segment Dx satisfy Dx=Lx / 1.1.

[0011] Optionally, impact vibration signals are applied to the sections of cable reel along the route, including: Each section of cable along the route is divided into at least one tapping point; A hammer is used to apply a striking vibration signal to each striking point at a preset frequency.

[0012] Optionally, the weight of the leather mallet is greater than or equal to 500 grams; The preset frequency is 1Hz.

[0013] Optionally, the optical cable vibration detection device includes a narrow linewidth light source, an acousto-optic modulator, a pulse amplifier, a circulator, an optical fiber amplifier, an optical fiber filter, a photodetector, a bandpass filter, and a host computer; The acousto-optic modulator is connected to the narrow linewidth light source and the pulse amplifier, respectively; the pulse amplifier and the fiber amplifier are connected through a circulator; the fiber filter is connected to the fiber amplifier and the photodetector, respectively; and the bandpass filter is connected to the photodetector and the host computer, respectively. The optical cable under test is connected to the pulse amplifier and the fiber amplifier via a circulator.

[0014] Optionally, the optical cable vibration detection device is connected to the optical cable under test and a pig is sent into the duct, including: Connect the circulator to the optical cable under test and send the pig inside the pipeline.

[0015] The technical solution of this invention has the following advantages: (1) The positioning method of pipeline-accompanying optical cable along the pipeline in this invention solves the problem of non-excavation positioning pipeline-accompanying optical cable along the pipeline and fills the gap; (2) The positioning method of the present invention can quickly locate the ground position of the optical cable coil along the pipeline, which is conducive to the rapid repair and maintenance of the optical cable; (3) The positioning method of the present invention is simple and easy to operate, and requires fewer personnel to find attenuation points and breakpoints; (4) This invention increases the convenience of optical cable maintenance and provides a powerful method and technical means for other work that requires the use of optical cable coils and optical cable wells.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a first method for positioning a pipeline-accompanying optical cable along a coiled route, according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a positioning detection structure provided according to an embodiment of the present invention; Figure 3 This is a first heat map provided according to an embodiment of the present invention; Figure 4 This is a flowchart of a second method for positioning a pipeline-accompanying optical cable along a coiled route, according to an embodiment of the present invention. Figure 5 This is a flowchart of a third method for positioning a pipeline-accompanying optical cable along a coiled route, according to an embodiment of the present invention. Figure 6 This is a second heat map provided according to an embodiment of the present invention; Figure 7 This is a flowchart of a fourth method for positioning cable coils along a pipeline, according to an embodiment of the present invention. Figure 8 This is a schematic diagram of applying a striking vibration signal according to an embodiment of the present invention; Figure 9This is a flowchart of the fifth method for positioning cable coils along a pipeline provided by an embodiment of the present invention; Figure 10 This is a flowchart of a sixth method for positioning a pipeline-accompanying optical cable along a route, according to an embodiment of the present invention. Figure 11 This is a connection diagram of an optical cable vibration detection device according to an embodiment of the present invention; Figure 12 This is a flowchart of the seventh method for positioning optical cables along a pipeline, according to an embodiment of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0021] Figure 1 This is a flowchart of a first method for positioning optical cables along a pipeline according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a positioning detection structure provided according to an embodiment of the present invention. (Combined with...) Figure 1 and Figure 2 As shown, the positioning method includes: S10. Connect the optical cable vibration detection device to the optical cable under test and send the pipeline pig inside the pipeline so that the pipeline pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test.

[0022] The optical cable vibration detection device 1 is a device for real-time monitoring of vibration signals along the optical cable, capturing minute vibrations generated along the optical cable through photoelectric conversion. The pipeline pig 4 is a device for cleaning, inspecting, and maintaining the inside of the pipeline 3, moving within the pipeline 3 driven by the pressure of the medium inside the pipeline 3. Since the detection object in this embodiment is the optical cable accompanying the buried pipeline 3, the optical cable 2 to be tested is set along the pipeline 3. When the pipeline pig 4 runs in the pipeline 3, the vibration generated by friction with the pipeline 3 can be transmitted to the optical cable 2 to be tested. The optical cable vibration detection device 1 can detect the position of the coiled cable 5 along the optical cable 2 by detecting the vibration of the optical cable 2 to be tested.

[0023] S11. Obtain the first heat map generated by the optical cable vibration detection device. The first heat map is a graph showing the relationship between the occurrence time and location of the vibration signal.

[0024] Figure 3 This is a first heat map provided according to an embodiment of the present invention, combined with Figure 1 , Figure 2 and Figure 3 As shown, the optical cable vibration detection device 1 can convert the optical signal in the optical cable 2 under test into an electrical signal and generate a first heat map after processing by an algorithm. In the first heat map, the horizontal axis represents the optical cable distance, from which the location of the vibration signal can be determined; the vertical axis represents the time of occurrence of the vibration signal. It can be seen from the first heat map that as the pig 4 operates, the optical cable 2 under test along the line exhibits vibration signals over time.

[0025] S12. Determine the distance section where the cable is located along the line based on the first heat map.

[0026] Among them, the distance segment where the cable reel is located can be the range of the area where cable reel 5 is located.

[0027] When the pig 4 passes the location of the optical cable coil, since the vibration signal sensed by the coil is at the same time, a line segment will appear on the first heat map where the distance of the optical cable changes but the time remains unchanged. The distance segment of the coil along the line can be determined by identifying the line segment in the first heat map.

[0028] S13. Determine the actual location of the cable reels along the route based on the distance of the cable reels along the route.

[0029] Among these, the actual location of the cable reel along the line can be further determined by detection based on the distance segment where the cable reel is located.

[0030] For example, a vibration detection device 1 for the accompanying optical cable of pipeline 3 is connected at the station or valve chamber. A pig 4 is sent inside pipeline 3. The pig 4 generates vibration signals by rubbing against the pipe wall. The vibration signals propagate to the optical cable 2 under test and are sensed by the optical cable vibration detection device 1 in the optical cable 2, thereby generating a first heat map. When the pig 4 passes the location of the optical cable coil, since the vibration signals sensed by the coil are at the same time, the first heat map shows a characteristic of constant time but changing position (as shown in segment c in the figure). If the vibration signal position near the optical cable remains unchanged, a straight line signal perpendicular to the distance axis as shown in a will appear; if the vibration signal near the optical cable moves parallel to pipeline 3, a diagonal line signal as shown in b will appear. As the pig 4 runs, all segments C on the first heat map are recorded and used as the distance segments where the coil is located along the line. The actual position of the coil along the line is determined by further detection based on the corresponding position of the distance segments where the coil is located along the line.

[0031] It is understood that the positioning method in the embodiments of the present invention can be applied to fields such as communication optical cables, oil and gas pipeline accompanying optical cables, buried track accompanying optical cables, etc., buried optical cable coils, optical cable junction boxes, and optical cable wells.

[0032] The technical solution of this invention has the following advantages: (1) The positioning method of pipeline-accompanying optical cable along the pipeline in the embodiments of the present invention solves the problem of non-excavation positioning pipeline-accompanying optical cable along the pipeline and fills the gap; (2) The positioning method of this invention can quickly locate the ground position of the optical cable coiled along the pipeline, which is conducive to the rapid repair and maintenance of the optical cable; (3) The positioning method of the present invention is simple and easy to operate, and requires fewer personnel to find attenuation points and breakpoints; (4) The embodiments of the present invention increase the convenience of optical cable maintenance and provide a powerful method and technical means for other work that needs to be carried out with the help of optical cable coils and optical cable wells.

[0033] Based on the above embodiments, Figure 4 This is a flowchart of a second method for positioning optical cables along a pipeline, according to an embodiment of the present invention, in conjunction with... Figures 2 to 4 As shown, the positioning method includes: S20. Connect the optical cable vibration detection device to the optical cable under test and send the pipeline pig inside the pipeline so that the pipeline pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test.

[0034] S21. Obtain the first thermal map generated by the optical cable vibration detection device.

[0035] S22. Obtain the detection mileage segment from the first heat map. The detection distance segment is the distance segment where the occurrence time of the vibration signal is fixed, but the location of the occurrence changes.

[0036] Due to the structure of the optical cable coil, when the pig 4 passes through the location of the optical cable coil, the vibration signal sensed by the optical cable coil is at the same moment. Therefore, the time remains unchanged, but the position changes. By identifying this feature, all detection mileage segments in the first heat map can be determined.

[0037] S23. The detection mileage section is taken as the distance section where the cable is located along the line.

[0038] S24. Determine the actual location of the cable reels along the route based on the distance of the cable reels along the route.

[0039] For example, a first heat map is obtained; all detection mileage segments in the first heat map (segment c in the figure) are identified, and the corresponding occurrence position Lx of the detection mileage segment is recorded until the pig 4 reaches the end point, and all occurrence positions L1 to Ln are recorded, that is, all distance segments where the cable coils are located along the line.

[0040] The technical solution of this invention, through the cooperation of the pipeline cleaning device 4 and the optical cable vibration detection device 1, achieves rapid positioning of the distance section where the cable is coiled along the pipeline, solves the problem of the optical cable coiling along the non-excavation positioning pipeline, and increases the convenience of optical cable maintenance.

[0041] Based on the above embodiments, Figure 5 This is a flowchart of a third method for positioning optical cables along a pipeline, according to an embodiment of the present invention, in conjunction with... Figure 2 , Figure 3 and Figure 5 As shown, the positioning method includes: S30. Connect the optical cable vibration detection device to the optical cable under test and send the pipeline pig inside the pipeline so that the pipeline pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test.

[0042] S31. Obtain the first thermal map generated by the optical cable vibration detection device.

[0043] S32. Determine the distance segment where the cable is located along the line based on the first heat map.

[0044] S33. Apply impact vibration signals to the sections of cable reel along the line.

[0045] The vibration signal can be generated by striking the cable with a rubber mallet. After determining the distance section where the cable coils are located along the line, the staff can apply the vibration signal based on the actual location of the cable coils. This vibration signal can be transmitted to the optical cable 2 under test, and then a second heat map can be generated based on the optical cable vibration detection device 1.

[0046] Understandably, to avoid confusion between the impact vibration signal and other ground vibrations, an impact vibration signal that is distinct from its interference signals can be set.

[0047] Since the distance segment where the cable coils are located is a single distance segment, the tapping vibration signal can be set at preset intervals to ensure accurate detection of the actual position of the cable coils 5 along the line.

[0048] S34. Obtain the second heat map generated by the optical cable vibration detection device. The second heat map is a graph showing the relationship between the occurrence time and location of the impact vibration signal.

[0049] Figure 6 This is a second heat map provided according to an embodiment of the present invention, such as... Figure 6 As shown, the second heat map can be an image generated based on the impact vibration signal. When a feature with a fixed time and a changing position appears in the second heat map, it indicates that this position is the actual position of the cable coil 5 along the line, and thus the actual position of the cable coil along the line can be identified through the second heat map.

[0050] S35. Determine the actual location of the cable coils along the line based on the second heat map.

[0051] It is understood that in this embodiment of the invention, the distance segment where the cable coil is located along the line is determined by the first heat map, and the knocking vibration signal is continued to be applied according to the distance segment where the cable coil is located along the line, and the actual position of the cable coil along the line is determined according to the second heat map.

[0052] The technical solution of this invention can accurately locate the ground position of the optical cable coil along the pipeline, thus avoiding land compensation and losses caused by large-scale excavation; at the same time, the location of the optical cable coil 5 along the pipeline 3 can locate the ground position of the optical cable well with the optical cable coil.

[0053] Based on the above embodiments, Figure 7 This is a flowchart of the fourth method for positioning optical cables along a pipeline according to an embodiment of the present invention. Figure 8 This is a schematic diagram of applying a striking vibration signal according to an embodiment of the present invention, combined with... Figure 2 , Figure 3 , Figure 6 , Figure 7 and Figure 8 As shown, the positioning method includes: S40. Connect the optical cable vibration detection device to the optical cable under test and send the pipeline pig inside the pipeline so that the pipeline pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test.

[0054] S41. Obtain the first thermal map generated by the optical cable vibration detection device.

[0055] S42. Determine the distance segment where the cable is located along the line based on the first heat map.

[0056] S43. Apply impact vibration signals to the sections of cable reel along the line.

[0057] S44. Obtain the second thermal map generated by the optical cable vibration detection device.

[0058] S45. Obtain the detection position in the second heat map. The detection position is the position corresponding to the point where the occurrence time of the impact vibration signal begins to be fixed.

[0059] Among them, under the action of the impact vibration signal, when the impact vibration signal is applied to the position of the cable coil 5 along the line, the second heat map shows a situation where the time is fixed and the position changes. The detection position refers to the position of the optical cable 2 under test when the time starts to be fixed.

[0060] It is understandable that when a detection position is detected, it indicates that the impact vibration signal has been applied to the corresponding position of the cable reel 5 along the line. Therefore, this detection position is recorded and used as the actual position of the cable reel along the line. For example, the positions corresponding to L1, Lx, and Ln in the figure.

[0061] S46. The detection location is taken as the actual location of the cable coil along the line.

[0062] The technical solution of this invention accurately locates the ground position of the optical cable coiled along the pipeline by identifying the second heat map.

[0063] Based on the above embodiments, Figure 9 This is a flowchart of the fifth method for positioning optical cables along a pipeline according to an embodiment of the present invention, combined with... Figure 2 , Figure 3 , Figure 6 , Figure 8 and Figure 9 As shown, the positioning method includes: S50. Connect the optical cable vibration detection device to the optical cable under test and send the pipeline pig inside the pipeline so that the pipeline pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test.

[0064] S51. Obtain the first heat map generated by the optical cable vibration detection device.

[0065] S52. Determine the distance section where the cable is located along the line based on the first heat map.

[0066] S53. Calculate the actual distance segment based on the distance segment where the cable is located along the line.

[0067] Since the actual location of pipeline 3 on the ground may deviate to some extent, the actual distance segment can be calculated after determining the distance segment where the cable is located along the route. In some embodiments, the distance segment Lx where the cable is located along the route and the actual distance segment Dx satisfy the condition Dx = Lx / 1.1.

[0068] S54. Apply impact vibration signals to the actual distance segments respectively.

[0069] After calculating the actual distance segment, staff can apply a tapping vibration signal to the corresponding position on the ground according to the actual distance segment, which further ensures the accuracy of the actual position of the cable coils along the line.

[0070] S55. Obtain the second heat map generated by the optical cable vibration detection device. The second heat map is a graph showing the relationship between the occurrence time and location of the impact vibration signal.

[0071] S56. Determine the actual location of the cable coils along the line based on the second heat map.

[0072] Based on the above embodiments, Figure 10 This is a flowchart of the sixth method for positioning cable coils along a pipeline according to an embodiment of the present invention, combined with... Figure 2 , Figure 3 , Figure 6 , Figure 8 and Figure 10 As shown, the positioning method includes: S60. Connect the optical cable vibration detection device to the optical cable under test and send a pig in the pipeline so that the pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test.

[0073] S61. Obtain the first thermal map generated by the optical cable vibration detection device.

[0074] S62. Determine the distance segment where the cable is located along the line based on the first heat map.

[0075] S63. Divide each section of cable along the line into at least one striking point.

[0076] The striking point can be the location where a striking vibration signal is applied. To ensure the accuracy of the actual position of the cable reel along the line, multiple striking points can be divided into sections for each cable reel. For example, one striking point can be set up every 10 meters.

[0077] S64. Use a leather hammer to apply a striking vibration signal to each striking point at a preset frequency.

[0078] A hammer 6 can be used to apply a striking vibration signal. In some embodiments, the weight of the hammer 6 is greater than or equal to 500 grams; the preset frequency is 1 Hz to distinguish it from other interfering vibration signals.

[0079] S65. Obtain the second heat map generated by the optical cable vibration detection device. The second heat map is a graph showing the relationship between the occurrence time and location of the impact vibration signal.

[0080] S66. Determine the actual location of the cable coils along the line based on the second heat map.

[0081] The technical solution of this invention further improves the positioning accuracy of the cable reel 5 by dividing each distance segment along the cable reel into striking points and applying striking vibration signals by a hammer 6 according to the striking points.

[0082] Optional, Figure 11 This is a connection diagram of an optical cable vibration detection device according to an embodiment of the present invention, combined with... Figure 2 and Figure 11 As shown, the optical cable vibration detection device 1 includes a narrow linewidth light source 11, an acousto-optic modulator 12, a pulse amplifier 13, a circulator 14, an optical fiber amplifier 15, an optical fiber filter 16, a photodetector 17, a bandpass filter 18, and a host computer 19. The acousto-optic modulator 12 is connected to the narrow linewidth light source 11 and the pulse amplifier 13, respectively; the pulse amplifier 13 and the fiber optic amplifier 15 are connected through the circulator 14; the fiber optic filter 16 is connected to the fiber optic amplifier 15 and the photodetector 17, respectively; and the bandpass filter 18 is connected to the photodetector 17 and the host computer 19, respectively. The optical cable under test 2 is connected to the pulse amplifier 13 and the fiber amplifier 15 through the circulator 14. Among them, the narrow linewidth light source 11 can be used to emit optical signals with continuous wavelengths, for example, optical signals with a wavelength of 1550nm; the acousto-optic modulator 12 can be used to modulate the continuous optical signal into an optical pulse signal, for example, modulated into a 20ns pulse width optical pulse signal; the pulse amplifier 13 can be used to amplify the optical pulse signal; the circulator 14 can be used to split the pulse light and the backscattered Rayleigh light signal incident on the optical cable 2 under test; the optical fiber amplifier can be used to amplify the backscattered light signal; the fiber optic filter 16 can be used to filter out optical noise; the photodetector 17 can be used to convert the optical signal into an electrical analog signal for subsequent filtering and acquisition processing; the bandpass filter 18 can be used to filter out noise and interference signals of the analog signal; and the host computer 19 can be used to perform acquisition, normalization algorithm and other processing, and display the results in the form of vibration waveform.

[0083] Specifically, the narrow-linewidth light source 11 emits a continuous light signal with a wavelength of 1550nm. The continuous light signal enters the acousto-optic modulator 12 to modulate a 20ns pulse width light pulse signal. The light pulse signal enters the pulse amplifier 13 for amplification. The amplified light pulse signal enters the optical cable under test 2 through the circulator 14. The backscattered Rayleigh light signal returns to the circulator 14 through the optical cable under test and enters the fiber amplifier 15 for amplification. The amplified scattered light signal enters the fiber filter 16 to filter out optical noise. The noise-filtered light signal enters the photodetector 17 to be converted into an electrical analog signal. The analog signal enters the bandpass filter 18 to filter out noise and interference signals. The filtered analog signal is transmitted to the host computer 19 for acquisition, normalization algorithm, heat map generation algorithm, and other processing. The results are displayed on the screen in the form of a first heat map.

[0084] The heat map output by the optical cable vibration detection device 1 in this embodiment of the invention is a real-time heat map, which is refreshed in real time by scrolling upwards along the longitudinal axis, with a refresh frequency of 0.1s to 2s / time. If the position of the vibration signal near the optical cable remains unchanged, a straight line signal perpendicular to the distance axis as shown in a will appear; if the vibration signal near the optical cable moves parallel to the pipe 3, a diagonal line signal as shown in b will appear.

[0085] Based on the above embodiments, Figure 12 This is a flowchart of the seventh method for positioning optical cables along a pipeline, according to an embodiment of the present invention, in conjunction with... Figure 2 and Figure 12 As shown, the positioning method includes: S70. Connect the circulator to the optical cable under test and send the pig inside the pipeline.

[0086] When installing the optical cable vibration detection device 1, the circulator 14 can be connected to the optical cable 2 to be tested and the pig 4 can be sent in the pipeline 3.

[0087] S71. Obtain the first heat map generated by the optical cable vibration detection device. The first heat map is a graph showing the relationship between the occurrence time and location of the vibration signal.

[0088] S72. Determine the distance segment where the cable is located along the line based on the first heat map.

[0089] S73. Determine the actual location of the cable reels along the route based on the distance segment where the cable reels are located.

[0090] The technical solution of this invention has the following advantages: (1) The positioning method in the embodiments of the present invention solves the problem of cable coiling along the pipeline for non-excavation positioning, and fills the gap; (2) The embodiments of the present invention can quickly locate the ground position of the optical cable coil along the pipeline, which is conducive to the rapid repair and maintenance of the optical cable; (3) The embodiments of the present invention can accurately locate the ground position of the optical cable coil along the pipeline within 5 meters, which can avoid land compensation and losses caused by large-scale excavation; (4) The embodiment of the present invention can locate the ground location of the optical cable well with the optical cable reel along the pipeline by positioning the optical cable coil along the pipeline. (5) The positioning method of the present invention is simple and easy to operate, and requires fewer personnel to find attenuation points and breakpoints; (6) The embodiments of the present invention increase the convenience of optical cable maintenance and provide a powerful method and technical means for other work that requires the use of optical cable coils and optical cable wells.

[0091] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0092] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for positioning optical cables coiled along a pipeline, characterized in that, include: The optical cable vibration detection device is connected to the optical cable under test and a pipeline pig is sent into the pipeline so that the pipeline pig acts in the pipeline to generate vibration and transmits the vibration to the optical cable under test. The optical cable vibration detection device detects the vibration signal of the optical cable under test. Obtain a first heat map generated by the optical cable vibration detection device; wherein, the first heat map is a relationship diagram of the occurrence time and occurrence location of the vibration signal; The distance segment where the cable coils are located along the line is determined based on the first heat map; The actual location of the cable reel along the route is determined based on the distance segment where the cable reel is located.

2. The positioning method according to claim 1, characterized in that, The distance segment where the cable reel is located along the line is determined based on the first heat map, including: Obtain the detection mileage segment from the first heat map; wherein, the detection distance segment is the distance segment where the occurrence time of the vibration signal is fixed and the occurrence position changes; The detected mileage segment is taken as the distance segment where the cable is located along the line.

3. The positioning method according to claim 1, characterized in that, Determining the actual location of the cable reels along the route based on the distance segment where the cable reels are located includes: A striking vibration signal was applied to the section of the cable reel along the line at the respective distances; Obtain the second heat map generated by the optical cable vibration detection device; wherein, the second heat map is a relationship diagram of the occurrence time and occurrence location of the impact vibration signal; The actual location of the cable coils along the route is determined based on the second heat map.

4. The positioning method according to claim 3, characterized in that, Determining the actual location of the cable reel along the route based on the second heat map includes: Obtain the detection position in the second heat map; wherein, the detection position is the position corresponding to the occurrence time of the impact vibration signal when it begins to be fixed; The detected location is taken as the actual location of the cable coil along the line.

5. The positioning method according to claim 3, characterized in that, Apply impact vibration signals to the sections of the cable reel along the route, including: Calculate the actual distance segment based on the distance segment where the cable coils are located along the route; A knocking vibration signal is applied to each of the actual distance segments.

6. The positioning method according to claim 5, characterized in that, The distance segment Lx where the cable is located along the line and the actual distance segment Dx satisfy the condition Dx=Lx / 1.

1.

7. The positioning method according to claim 3, characterized in that, Apply impact vibration signals to the sections of the cable reel along the route, including: Each section of the cable reel along the route is divided into at least one striking point; A hammer is used to apply a striking vibration signal to each striking point at a preset frequency.

8. The positioning method according to claim 7, characterized in that, The weight of the hammer is greater than or equal to 500 grams; The preset frequency is 1Hz.

9. The positioning method according to claim 1, characterized in that, The optical cable vibration detection device includes a narrow linewidth light source, an acousto-optic modulator, a pulse amplifier, a circulator, an optical fiber amplifier, an optical fiber filter, a photodetector, a bandpass filter, and a host computer. The acousto-optic modulator is connected to the narrow linewidth light source and the pulse amplifier, respectively; the pulse amplifier and the fiber amplifier are connected through the circulator; the fiber filter is connected to the fiber amplifier and the photodetector, respectively; the bandpass filter is connected to the photodetector and the host computer, respectively. The optical cable under test is connected to the pulse amplifier and the fiber amplifier through the circulator.

10. The positioning method according to claim 9, characterized in that, Connect the optical cable vibration detection device to the optical cable under test and send the pipeline pig inside the pipeline, including: The circulator is connected to the optical cable under test and a pig is sent into the pipeline.

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