Intelligent leakage early warning flexible composite pipeline system and early warning method

Abstract

The invention relates to the technical field of oil and gas transmission, and discloses an intelligent leakage early warning flexible composite pipeline system and an early warning method.The system comprises a composite pipeline body, an optical signal processing device and a data processing unit, and the optical signal processing device is in communication connection with the data processing unit to achieve data transmission. The early warning method corresponds to the system. According to the invention, intelligent leakage early warning and monitoring of the flexible composite pipeline system are realized; the distributed temperature sensing element can sense the temperature change of the pipeline; the optical signal processing device converts the laser signal into an electric signal and transmits the electric signal to the data processing unit; the data processing unit calculates the on-way temperature and the leakage position of the pipeline and gives an alarm for abnormal data; the problem that a traditional flexible composite pipe lacks a sensing function is solved, environmental pollution and energy loss caused by pipe transportation oil gas leakage are effectively reduced, safety and stability of oil gas transportation are guaranteed, and the intelligent development of the composite pipeline industry is promoted.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas transportation, and specifically to an intelligent leakage warning flexible composite pipeline system and a warning method. Background Art

[0002] As a new type of composite pipe, flexible composite pipe is widely used in the field of oil and gas transportation. Flexible composite pipe is usually composed of inner lining layer, reinforcement layer and outer protective layer. The inner lining layer and outer protective layer are usually made of thermoplastic materials such as high-density polyethylene and cross-linked polyethylene, and are formed by extrusion process; the reinforcement layer is usually made of high-strength materials such as polyester industrial filament, aramid rope / filament, glass fiber prepreg tape, steel curtain rope prepreg tape, steel belt, steel wire (rope), etc., and is compounded on the surface of the inner lining layer in a symmetrical even-numbered structure at a specific winding angle through precision winding equipment. The length of a single pipe can reach 150~2000m, which is 40%~60% lighter than traditional steel pipes. Due to its advantages of light weight, coiling, fast construction speed, corrosion resistance and long service life, it has been applied in large-scale engineering in key areas such as oil, gas and water transportation, onshore shale gas development, carbon dioxide oil injection and production pipelines, and hydrogen energy storage and transportation systems, becoming an important part of the modern energy transportation system.

[0003] However, the existing flexible composite pipes still have limitations when used as a transportation carrier. The inventors studied the application of existing flexible composite pipes and found that the existing flexible composite pipes lack perception functions, that is, when the pipeline encounters third-party construction damage or extreme stress, the medium leakage caused by the damage to the pipe body not only causes energy waste and ecological environmental pollution, but also when transporting associated gas containing hydrogen sulfide or green hydrogen with a hydrogen purity of more than 99%, pipeline failure will cause harmful gas escape and combustible gas leakage, resulting in major safety accidents such as poisoning and explosion.

[0004] Based on this, the industry is vigorously promoting the intelligent technology iteration of flexible composite pipes, and building an intelligent pipeline system with real-time strain monitoring, precise leakage positioning and risk autonomous warning functions by integrating various sensors in the pipeline. For example, the domestic patent ZL201520095997.3 pre-buries the optical fiber micro-tube in the wall structure of the flexible composite pipe to build an integrated optical fiber-tube composite system; this structure not only retains the mechanical properties of the traditional flexible composite pipe, but also gives the pipeline distributed optical fiber sensing capabilities, which can realize real-time leakage monitoring of the entire pipeline; but in this solution, first, the wall thickness of the lining layer of the flexible composite pipe is greatly increased, which increases the production cost; second, the communication optical fiber embedded in the lining layer inevitably causes local stress concentration, affecting the service life of the pipe; third, the non-standard design of pipes, joints, etc. restricts the large-scale market promotion and application, so there have been no related engineering application cases so far. U.S. Patent US9658421B2 relates to a flexible composite pipe, including a multilayer structure of a metal skeleton layer, a polymer sealing layer, a Z-shaped steel belt compression armor layer, a spiral steel wire tensile armor layer and a polyethylene outer protective layer, and a communication optical fiber array is implanted in the interlayer space between the tensile armor layer and the outer protective layer, and a double protection mechanism is formed through the physical isolation of the armored steel wire, so that the optical fiber signal is transmitted stably; this type of pipe has a complex structure and high cost, and is only used for marine flexible risers, which is not conducive to promotion and application in onshore oil and gas fields. Traditional fiber optic early warning technology is to arrange sensing optical fibers outside the pipeline to monitor the stress and temperature field of the target pipeline and achieve the purpose of pipeline leakage early warning. For example, in patent ZL201410158614.2, a protective sleeve with built-in sensing optical fibers is laid in parallel on the outside of the buried steel pipeline. Sensor holes are set at the bottom of the protective sleeve at regular intervals. The optical fiber sensor extends out of the protective sleeve through the sensor hole and is fixed to the outer wall of the monitoring pipeline to achieve real-time monitoring of the pipeline. This technology is cumbersome to operate and is difficult to construct in the face of complex and harsh working conditions on site. Therefore, it has not been promoted and applied so far.

[0005] In summary, how to organically combine the sensing optical fiber early warning technology with the flexible composite pipe technology, develop a flexible composite pipe with intelligent early warning function, realize real-time monitoring of pipeline integrity, and analyze it through intelligent algorithms to establish an intelligent early warning system, which is of great significance to reducing oil and gas losses caused by pipeline failure, realizing green and environmental protection of oil fields, and promoting the intelligent development of the composite pipeline industry. Summary of the invention

[0006] The purpose of this application is to provide an intelligent leakage warning flexible composite pipeline system and a warning method to solve the technical problems raised in the above background technology.

[0007] To achieve the above objectives, this application discloses the following technical solutions: In a first aspect, the present application discloses an intelligent leakage warning flexible composite pipeline system, comprising: A composite pipe body, comprising an inner lining layer, a reinforcement layer, an inner protective layer, at least one thermal insulation layer, and a distributed temperature sensing element integrated into the outer wall of the composite pipe; An optical signal processing device, used to transmit an optical signal to the distributed temperature sensing element, receive reflected light and convert it into temperature data; A data processing unit, used to calculate the temperature distribution along the pipeline and the leakage position based on the temperature data, and trigger an abnormal alarm; The distributed temperature sensing element senses temperature changes through optical characteristics, and the optical signal processing device is communicatively connected with the data processing unit to realize data transmission.

[0008] Preferably, the temperature along the pipeline is determined based on the power ratio of Stokes light to anti-Stokes light in combination with a preset heat conduction model; The leakage position is determined by a mapping relationship between the optical signal transmission time and the optical fiber path parameters.

[0009] Preferably, the temperature along the pipeline is calculated by the following formula:

[0010] in, It is the preset initial reference temperature, used as the basis for temperature calculation; It is a coefficient related to the heat conduction characteristics of the pipeline, which is used to reflect the heat conduction capacity of the pipeline material; It is the convection heat transfer coefficient, which is used to reflect the heat exchange efficiency between the pipeline and the surrounding environment or the internal fluid; It is the change in flow velocity of the fluid in the pipeline, which is used to reflect the influence of heat transfer and temperature distribution; For the temperature When , the optical power value of anti-Stokes light; For the temperature When , the optical power value of Stokes light; At the initial reference temperature When , the optical power value of anti-Stokes light; At the initial reference temperature The optical power value of Stokes light at .

[0011] Preferably, the leakage position is calculated by the following formula:

[0012] in, Sense the length of the optical fiber from the starting point of the optical fiber connected to the device to the leakage point; is the pitch of the sensing optical fiber wound on the insulation layer; is the outer diameter of the composite pipe body; is the thickness of the outer protective layer; It is the distance from the starting point of the optical fiber connected to the equipment to the end where the optical fiber enters the composite pipe body; is the propagation speed of light in the distributed temperature sensing element; is the time interval from the emission of the optical signal to the reception of the reflected optical signal; is the refractive index of the optical fiber.

[0013] Preferably, the distributed temperature sensing element is a multi-core structure and is wound around the outside of the insulation layer at a preset angle, and achieves signal continuity through optical coupling technology; The reinforcement layer is made of high-strength material and is wound around the outside of the inner lining layer at a preset angle.

[0014] Preferably, the composite pipe body is provided with a detachable joint, which comprises a core sleeve and an outer sleeve connected by an inner snap-on or threaded connection, and the core sleeve and the outer sleeve seal the inner lining layer, the reinforcing layer and the protective layer through mechanical bite and sealing.

[0015] Preferably, the composite pipe body is provided with an optical fiber connector, which realizes continuous signal transmission through hot-melt welding or optical coupler, and the outer layer of the optical fiber connector is an anti-corrosion coating.

[0016] Preferably, the data processing unit uses a dynamic data correction algorithm to filter abnormal temperature fluctuations, and the filtering of abnormal temperature fluctuations specifically includes: reducing false alarms caused by environmental interference or sensor noise.

[0017] Preferably, the dynamic data correction algorithm is specifically:

[0018] in, is the calculated abnormal data point The replacement data, is the sequence number of the abnormal data point, The offset variable.

[0019] In a second aspect, the present application discloses an intelligent leakage warning flexible composite pipeline early warning method, which is applied to the intelligent leakage warning flexible composite pipeline system as described above, and the method comprises the following steps: S1: configuring a composite pipe body, wherein the composite pipe body comprises an inner lining layer, a reinforcement layer, an inner protective layer, at least one thermal insulation layer, and a distributed temperature sensing element integrated on an outer wall of the composite pipe; S2: transmitting a laser signal to a distributed temperature sensing element through an optical signal processing device; S3: collecting reflected light through an optical signal processing device and converting it into temperature data; S4: The data processing unit analyzes the temperature distribution based on the temperature data. If a temperature anomaly is detected, the temperature distribution along the pipeline and the leakage position are calculated, and an abnormality alarm is issued.

[0020] Beneficial effects: The intelligent leakage warning flexible composite pipeline system and warning method of the present application utilize a composite pipeline body, in combination with an optical signal processing device and a data processing unit, to realize intelligent leakage warning and monitoring of the flexible composite pipeline system; the various layers of the composite pipeline body work together, and the distributed temperature sensing elements sense changes in pipeline temperature; the optical signal processing device converts the laser signal into an electrical signal and transmits it to the data processing unit; the data processing unit analyzes the electrical signal, calculates the temperature and leakage location along the pipeline, and alarms for abnormal data; the entire system is organically combined, which solves the problem of the lack of perception function of traditional flexible composite pipes, can effectively reduce environmental pollution and energy loss caused by pipeline oil and gas leakage, ensure the safety and stability of oil and gas transportation, and promote the development of the composite pipeline industry towards intelligence. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic diagram of the structure of an intelligent leakage warning flexible composite pipeline system provided in an embodiment of the present application; Figure 2 The structural intention of the composite pipe body provided in the embodiment of the present application; Figure 3 A schematic diagram of a composite pipe body intermediate joint connection provided in an embodiment of the present application; Figure 4 A schematic diagram of a joint connection at the end of a composite pipe body provided in an embodiment of the present application; Figure numerals: 1. composite pipe body; 11. inner lining layer; 12. reinforcement layer; 13. inner protective layer; 14. thermal insulation layer; 15. distributed temperature sensing element; 16. optical cable sheath; 17. outer protective layer; 2. core sleeve; 21. core sleeve thread; 22. O-ring; 3. outer sleeve; 31. outer sleeve thread; 4. nut; 5. sensor connection point; 6. heat shrink sleeve; 7. flange; 8. optical signal processing device; 9. computer PC terminal. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0024] In this article, the term "comprising" is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, the elements defined by the sentence "comprising..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0025] The first aspect of this embodiment discloses an intelligent leakage warning flexible composite pipeline system, including: The composite pipe body 1 comprises an inner lining layer 11, a reinforcement layer 12, an inner protective layer 13, at least one thermal insulation layer 14, a distributed temperature sensing element 15 integrated in the outer wall of the protective layer, an optical cable wrapping layer 16 and an outer protective layer 17, wherein the reinforcement layer 12 is wound around the outside of the inner lining layer 11, the thermal insulation layer 14 is arranged at least outside the reinforcement layer 12, the distributed temperature sensing element 15 is arranged outside the thermal insulation layer 14, the optical cable wrapping layer 16 wraps the distributed temperature sensing element 15, and the outer protective layer 17 is arranged outside the optical cable wrapping layer 16; the distributed temperature sensing element 15 senses temperature changes through optical characteristics (such as the power ratio of Stokes light and anti-Stokes light); The optical signal processing device 8 is used to transmit an optical signal to the distributed temperature sensing element 15, receive reflected light and convert it into temperature data; the optical signal processing device 8 can be any one of the prior art, and is composed of electronic components such as a laser, a modulator, an amplifier, a signal receiver, a photoelectric converter, and an information transmitter, wherein the laser emits laser light, which is injected into the distributed temperature sensing element 15 after passing through the modulator and the amplifier, the signal receiver separates the Stokes light and the anti-Stokes light in the reflected light, and the photoelectric converter converts the optical signal into an electrical signal, which is transmitted to the data processing unit through the information transmitter; The data processing unit is used to calculate the temperature distribution and leakage position along the pipeline based on the temperature data and trigger an abnormal alarm; the optical signal processing device 8 is connected to the data processing unit for communication to achieve data transmission. The carrier of the data processing unit is a computer PC terminal 9.

[0026] As a preferred implementation of this embodiment, the material of the inner lining layer 11 is usually preferably polyethylene, cross-linked polyethylene, polyvinylidene fluoride, nylon, polyphenylene sulfide, or other single-layer / multi-layer thermoplastic resins; the reinforcement layer 12 is selected from non-metallic or metal reinforcement materials, such as polyester industrial filament, aramid, fiber or steel cord prepreg tape, steel wire rope (wire), steel belt, etc.; the inner protective layer 13 is usually selected from thermoplastic resins such as polyethylene resin. Generally, the thickness of each layer of the inner lining layer 11, the reinforcement layer 12, and the inner protective layer 13 complies with the requirements of national standards and standards such as GB / T 38725.2-2020, SY / T 6662.2, and SY / T 6662.4. The insulation layer 14 can be made of high-performance insulation materials such as nano aerogel felt, rubber and plastic sponge, etc., and its thickness is set according to the pipeline laying process design results or the owner's requirements; the distributed temperature sensing element 15 uses two 2-core optical cables interlaced and wound on the outside of the insulation layer 14 (it can also be laid on the outside of the insulation layer 14 in a straight manner), and is fixed with PET tape, and the outer protective layer 17 is usually made of wear-resistant polyethylene.

[0027] Based on the above, this embodiment utilizes the composite pipe body 1, in combination with the optical signal processing device 8 and the data processing unit, to realize intelligent leakage warning and monitoring of the flexible composite pipe system. The various layers of the composite pipe body 1 work together, and the distributed temperature sensing element 15 senses the temperature change of the pipe; the optical signal processing device 8 converts the laser signal into an electrical signal and transmits it to the data processing unit; the data processing unit analyzes the electrical signal, calculates the temperature and leakage position along the pipe, and alarms for abnormal data. The entire system is organically combined to solve the problem of the lack of sensing function of traditional flexible composite pipes, which can effectively reduce environmental pollution and energy loss caused by pipeline oil and gas leakage, ensure the safety and stability of oil and gas transportation, and promote the development of the composite pipeline industry towards intelligence.

[0028] In this embodiment, the temperature along the pipeline is determined based on the power ratio of Stokes light to anti-Stokes light, combined with a preset heat conduction model (such as the thermal properties of the pipeline material and the fluid convection heat transfer coefficient). Specifically, the temperature along the pipeline is calculated using the following formula:

[0029] in, The calculated real-time temperature value of a certain point along the pipeline; It is the preset initial reference temperature, used as the basis for temperature calculation; It is a coefficient related to the heat conduction characteristics of the pipeline, which is used to reflect the heat conduction capacity of the pipeline material; It is the convection heat transfer coefficient, which is used to reflect the heat exchange efficiency between the pipeline and the surrounding environment or the internal fluid; It is the change in flow velocity of the fluid in the pipeline, which is used to reflect the influence of heat transfer and temperature distribution; For the temperature When , the optical power value of anti-Stokes light; For the temperature When , the optical power value of Stokes light; At the initial reference temperature When , the optical power value of anti-Stokes light; At the initial reference temperature The optical power value of Stokes light at .

[0030] Based on the above, this embodiment uses the temperature calculation formula, combined with various parameters under the actual working conditions of the pipeline, to achieve accurate calculation of the temperature along the pipeline. By determining the initial reference temperature, pipeline thermal conductivity coefficient, convection heat transfer coefficient, fluid flow rate change, and Stokes light and anti-Stokes light power values ​​and other parameters, they are substituted into the formula for calculation. This enables the data processing unit to obtain temperature information at each point along the pipeline in real time, providing a key basis for subsequent judgment of whether there is a risk of leakage in the pipeline. Accurate temperature calculation improves the accuracy of leakage warning, avoids leakage accidents caused by temperature misjudgment, ensures safety during pipeline transportation, and provides strong support for the stable operation of oil and gas transportation.

[0031] In this embodiment, the leakage position is determined by the mapping relationship between the optical signal transmission time and the optical fiber path parameters (such as winding pitch and pipe diameter). Specifically, the leakage position is calculated by the following formula:

[0032] in, is the calculated leakage location length of the flexible composite pipe; Sense the length of the optical fiber from the starting point of the optical fiber connected to the device to the leakage point; is the pitch of the sensing optical fiber wound on the insulation layer; is the outer diameter of the composite pipe body; is the thickness of the outer protective layer; It is the distance from the starting point of the optical fiber connected to the equipment to the end where the optical fiber enters the composite pipe body; is the propagation speed of light in the distributed temperature sensing element; is the time interval from the emission of the optical signal to the reception of the reflected optical signal; is the refractive index of the optical fiber.

[0033] Based on the above, this embodiment uses a leakage position calculation formula that combines the sensing fiber parameters, pipeline structure dimensions, and optical signal propagation characteristics to achieve accurate positioning of the pipeline leakage position. The formula calculation is performed by determining the sensing fiber length from the starting point of the optical fiber connected to the leakage point, the sensing fiber winding pitch, the pipeline outer diameter, the thickness of the outer protective layer 17, the optical signal propagation speed, the propagation time interval, and the optical fiber refractive index. This enables the location of the leakage point to be quickly determined when a pipeline leaks, making it convenient for staff to take timely measures to repair it, reduce the losses caused by the leak, improve the emergency response capability of the pipeline system, and ensure the efficiency and safety of oil and gas transportation.

[0034] In this embodiment, the principle of using the temperature calculation formula and the leakage position calculation formula is: When the incident light power is , the relationship between Stokes optical power and temperature obeys equation 1, and the relationship between anti-Stokes optical power and temperature obeys equation 3: Formula 1 Right now: Formula 2 Formula 3 Formula 1 / Formula 3 gives: Formula 4 The sensing fiber is placed at an initial reference temperature Calibration is performed under the following conditions: Formula 5 Formula 2 / Formula 5 gives: Formula 6 Solving for temperature The value of is formula 7, which is the temperature calculation formula: Formula 7 In the formula, is the Stokes optical power; is the coefficient related to Stokes scattering; is the anti-Stokes optical power; is the coefficient related to anti-Stokes scattering; , , are the average propagation losses of incident light, Stokes light, and anti-Stokes light, respectively; is the Boltzmann factor of Stokes light; is the Boltzmann factor of anti-Stokes light; is the distance from the scattering point to the fiber entrance; is the speed of light propagation in the optical fiber.

[0035] In the process of light moving forward, if scattered light is generated and returns to the incident end, the time is By calculating the time difference between the reflected light and the incident light, the position of the emitted light in the optical fiber can be located. The calculation formula is as follows: Formula 8 in, is the distance between the scattering point in the optical fiber and the incident end face of the light source; is the speed of light; is the refractive index of the optical fiber.

[0036] When the sensing optical fiber is wound and laid outside the insulation layer 14, the pipeline length for: Formula 9.

[0037] Specifically, the reinforcing layer 12 is made of high-strength material and is wound around the outside of the inner lining layer 11 at a preset angle. The reinforcing layer 12 may be, but is not limited to, high-performance fiber filaments, metal tapes, or various fiber / metal filament prepreg tapes. The preset angles in this embodiment are all empirical values ​​known to those skilled in the art.

[0038] Based on the above, this embodiment uses high-performance fiber filaments, metal tapes or various fiber / metal wire prepreg tapes as the reinforcement layer 12, and winds it around the outside of the inner lining layer 11 at a preset angle, thereby achieving the effect of enhancing the strength and stability of the pipeline structure. Different reinforcement materials provide good mechanical properties, and the preset winding angle enables the reinforcement layer 12 to better withstand the internal pressure and external load of the pipeline. This effectively improves the compression and tensile resistance of the pipeline, reduces the risk of pipeline damage and leakage caused by external forces, extends the service life of the pipeline, ensures the stable operation of the pipeline in a complex oil and gas transportation environment, reduces maintenance costs, and ensures the reliability of energy transportation.

[0039] Specifically, the inner protective layer 13 is provided based on the design requirements of the composite pipeline body 1 , and the design requirements include but are not limited to the working pressure of the pipeline, the type of conveying medium, and the corrosiveness requirements.

[0040] Through the above, this embodiment realizes effective protection of the internal structure of the pipeline. According to different working pressures and medium corrosiveness, the appropriate material and thickness of the inner protective layer 13 are selected to prevent the erosion of the inner lining layer 11 and the reinforcement layer 12 by the conveying medium, and to avoid pipeline leakage caused by medium corrosion. At the same time, the inner protective layer 13 can also play a certain buffering role, reduce the impact of internal pressure on the pipeline structure, improve the corrosion resistance and reliability of the pipeline, and ensure the safe operation of the pipeline under different working conditions.

[0041] Specifically, the distributed temperature sensing element 15 is a multi-core structure and is wound around the outside of the insulation layer 14 at a preset angle, and signal continuity is achieved through optical coupling technology (such as forming an integrated structure by welding at the middle joint).

[0042] Through the above, this embodiment realizes stable and reliable signal transmission and monitoring functions. The multi-core structure increases the redundancy of signal transmission and improves the accuracy of data collection; the preset angle winding can better cover the pipeline surface and improve the comprehensiveness of temperature monitoring; the middle joint is welded to form an integrated structure, which reduces the loss and interference of signal transmission. This enables the distributed temperature sensing element 15 to stably collect pipeline temperature information, provide reliable data support for leakage warning, and ensure the safe and stable operation of the pipeline system.

[0043] Specifically, the composite pipe body 1 further includes a detachable joint, which includes a core sleeve 2 and an outer sleeve 3 connected in an inner buckle or threaded manner, and the core sleeve 2 and the outer sleeve 3 seal the inner lining layer 11, the reinforcement layer 12 and the protective layer through mechanical engagement and a sealant (such as an O-ring). It is feasible that the detachable joint includes a core sleeve 2 and an outer sleeve 3, and the inner and outer surfaces of the core sleeve 2 are provided with a serrated tooth pattern and an O-ring site, and the inner lining layer 11, the reinforcement layer 12, and the inner protective layer 13 of the composite pipe body 1 are tightly buckled and pressed between the core sleeve 2 and the outer sleeve 3 by the inner expansion of the core sleeve 2 or the inner buckling of the outer sleeve 3, and are sealed by the O-ring 22.

[0044] Through the above, this embodiment realizes the tight connection and reliable sealing of the various parts of the composite pipe body 1. By means of the inner expansion of the core sleeve 2 or the inner buckling of the outer sleeve 3, the pipeline lining layer 11, the reinforcement layer 12, and the inner protective layer 13 are tightly buckled between the core sleeve 2 and the outer sleeve 3, and then sealed with the O-ring 22, which effectively prevents leakage of the medium. This connection method is easy to operate and has a firm connection, which ensures the sealing and integrity of the pipeline system, improves the connection quality of the pipeline, ensures that oil and gas will not leak during the transportation process, and ensures the safety of energy transportation.

[0045] It is feasible that the composite pipe body 1 is provided with an optical fiber joint, and the optical fiber joint realizes continuous signal transmission through hot-melt welding or optical coupler. The outer layer of the optical fiber joint is an anti-corrosion coating (such as 3PE cold wrapping tape), and the distributed temperature sensing element 15 is spirally wrapped around the joint connection part, and the intelligent early warning flexible composite pipe and the joint at both ends are completely wrapped with a heat shrink sleeve 6, and strengthened by wrapping with 3PE cold wrapping tape; the end of the pipeline is connected to the inlet / outlet pipeline with a flange 7, and the same method as the middle joint is used for anti-corrosion protection.

[0046] Through the above, this embodiment achieves the stability and good anti-corrosion performance of the pipeline connection. The connection method in the middle ensures the firmness of the pipeline connection, and the winding and welding of the distributed temperature sensing element 15 ensure the continuity of signal transmission; the heat shrink sleeve 6 and 3PE cold wrapping tape effectively prevent corrosion of the connection part; the connection and anti-corrosion measures of the flange 7 at the end are unified with the middle part, so that the connection and anti-corrosion performance of the entire pipeline system are consistent. This reduces the risk of leakage at the pipeline connection, extends the service life of the pipeline, and ensures the stability of oil and gas transportation.

[0047] In this embodiment, the data processing unit uses a dynamic data correction algorithm to filter abnormal temperature fluctuations, and the filtering of abnormal temperature fluctuations is specifically to reduce false alarms caused by environmental interference or sensor noise. In a feasible implementation, the dynamic data correction algorithm is a ten-point data mean method, and the ten-point data mean method is specifically:

[0048] in, is the calculated abnormal data point The replacement data, is the sequence number of the abnormal data point, The offset variable.

[0049] Through the above, this embodiment achieves effective repair of temperature anomaly data and improvement of data reliability. By taking the average of the five data points before and after the abnormal data point (or taking the average of the thirty data points before and after in case of continuous anomalies) to replace the abnormal data, the cause of the anomaly can be accurately determined and the noise and interference in the data can be removed. This makes the data obtained by the data processing unit more accurate and reliable, provides more reliable data support for leakage warning, avoids misjudgment caused by data anomalies, improves the accuracy and stability of the leakage warning system, and ensures the safe and stable operation of the pipeline system.

[0050] In this embodiment, the abnormal data is processed using a ten-point data mean formula, which is: First, by real-time monitoring of temperature data, based on the temperature range of the abnormal data, it is possible to accurately determine whether the abnormality is caused by equipment failure, sensor error, or environmental interference, providing a basis for subsequent processing.

[0051] Secondly, for abnormal data, the mean of the five data points before and after is used for repair. The repaired data is T repaired and can be calculated by the following formula: Formula 10 When continuous abnormalities occur, such as three consecutive data points being abnormal, this method will further expand the data coverage to ensure the accuracy of the repair. At this time, the thirty data points before and after will be taken for average calculation to replace the continuous abnormal data segment, as follows: Formula 11 This method not only improves data reliability, but also restores data continuity and consistency without introducing additional errors, providing strong support for the safe operation and precise control of intelligent early warning flexible composite pipes.

[0052] A second aspect of the present embodiment discloses an intelligent leakage warning flexible composite pipeline early warning method, which is applied to the intelligent leakage warning flexible composite pipeline system as described above, and the method comprises the following steps: S1: configuring a composite pipe body 1, wherein the composite pipe body 1 comprises an inner lining layer 11, a reinforcement layer 12, an inner protective layer 13, at least one thermal insulation layer 14, and a distributed temperature sensing element 15 integrated on an outer wall of the composite pipe; S2: transmitting a laser signal to the distributed temperature sensing element 15 through the optical signal processing device 8; S3: collecting Stokes light and anti-Stokes light in the reflected light through the optical signal processing device 8, and converting them into temperature data; S4: The data processing unit analyzes the temperature distribution based on the temperature data. If a temperature anomaly is detected (such as exceeding a threshold or a sudden change), the temperature distribution along the pipeline and the leakage position are calculated, and an abnormality alarm is issued.

[0053] It should be noted that the intelligent leakage warning flexible composite pipeline warning method of this embodiment corresponds to the aforementioned intelligent leakage warning flexible composite pipeline system. Therefore, the contents not specifically described in the intelligent leakage warning flexible composite pipeline warning method of this embodiment may include but are not limited to functional definitions, working principles and technical effects, etc., and may refer to the records in the aforementioned intelligent leakage warning flexible composite pipeline system, and this text will not elaborate on them here.

[0054] In a specific application of this embodiment, Figures 1 to 4 As shown, a DN100mm / PN6.4MPa intelligent leakage warning flexible composite pipeline system is taken as an example. In the intelligent warning flexible composite pipe, the inner lining layer 11 is made of heat-resistant polyethylene, the reinforcement layer 12 is made of high-strength polyester industrial filament, the inner protective layer 13 is made of polyethylene, the insulation layer 14 is made of flexible insulation materials such as nano aerogel felt or rubber sponge, the distributed temperature sensing element 15 is made of 2 2-core optical cables, the optical cable wrapping layer 16 is made of PET tape, and the outer protective layer 17 is made of wear-resistant polyethylene.

[0055] The length of a single composite pipe body 1 is 200m, and the end of each composite pipe is connected by crimping a core sleeve 2 and an outer sleeve 3; during the crimping process, the core sleeve thread 21 and the outer sleeve thread 31 respectively bite the inside of the composite pipe lining layer 11 and the outside of the inner protective layer 13, and are tightly sealed by the O-ring 22 arranged on the core sleeve thread 21. The two sections of composite pipe are connected by the joint thread and the nut 4. The distributed temperature sensing element 15 is hot-melt welded at the sensor connection 5, spirally wrapped around the outer wall of the pipe, and protected by a heat shrink sleeve 6, and strengthened by wrapping with a 3PE cold wrapping tape; the end is connected to the inlet pipeline by a flange 7, and the distributed temperature sensing element 15 is connected to the optical signal processing device 8. The optical signal is converted into an electrical signal and then transmitted to the data processing unit for data analysis.

[0056] After the intelligent leakage warning flexible composite pipeline is put into operation, the laser in the optical signal processing device 8 emits laser light, which is injected into the distributed temperature sensing element 15 after passing through the modulator and amplifier. Then the signal receiver collects the Stokes light and anti-Stokes light scattered at each position of the pipeline, converts them into electrical signals through the photoelectric converter, and transmits them to the data processing unit for analysis and denoising, so as to realize pipeline leakage warning.

[0057] If the composite pipe body 1 transports oilfield sewage, the ambient temperature of the pipe The temperature is 25℃ (298K). When leakage occurs, the local temperature rises and the power changes of Stokes light and anti-Stokes light are detected as follows: When there is no leakage: ; In case of leakage: ; Other parameter values: 1.38×10-23J / K, is 6.626×10-34J·s, is 2.5×10-12HZ, at this time .

[0058] Since the normal ambient temperature of the intelligent leakage warning flexible composite pipeline is known to be 25°C, and the calculated temperature at the detection point reaches 49°C, it indicates that there may be a gas leak at this location. Therefore, a temperature threshold (such as 35°C) can be set in this system, and an early warning is triggered once the monitoring value exceeds the temperature threshold.

[0059] If in the intelligent leakage warning flexible composite pipeline system, the data processing unit data shows that the optical fiber at 1000m has an abnormal temperature alarm, then the theoretical alarm time for:

[0060] If the diameter of the composite pipe body 1 127mm, outer protective layer 17mm thick is 3.5 mm, the diameter of the distributed temperature sensing element 15 is negligible relative to the diameter of the composite tube, and the fiber winding pitch The length from the optical signal processing device 8 to the distributed temperature sensing element 15 entering the composite tube is 50m, and the length of the leakage warning optical fiber is is 1000m, then the length of the composite pipe at the leak point is .

[0061] In summary, the intelligent leakage warning flexible composite pipeline system and warning method of this embodiment utilizes a composite pipeline body 1 composed of an inner lining layer 11, a reinforcement layer 12, an inner protective layer 13, an insulation layer 14, a distributed temperature sensing element 15, an optical cable wrapping layer 16 and an outer protective layer 17, in combination with an optical signal processing device 8 and a data processing unit, to realize intelligent leakage warning and monitoring of the flexible composite pipeline system; the various layers of the composite pipeline body 1 work together, and the distributed temperature sensing element 15 can sense changes in pipeline temperature; the optical signal processing device 8 converts the laser signal into an electrical signal and transmits it to the data processing unit; the data processing unit analyzes the electrical signal, calculates the temperature and leakage position along the pipeline, and alarms for abnormal data; the entire system is organically combined, which solves the problem of the lack of perception function of traditional flexible composite pipes, can effectively reduce environmental pollution and energy loss caused by pipeline oil and gas leakage, ensure the safety and stability of oil and gas transportation, and promote the development of the composite pipeline industry towards intelligence.

[0062] In the embodiments provided in the present application, it should be understood that the embodiments described herein can be implemented in hardware, software, firmware, middleware, code, or any appropriate combination thereof. For hardware implementation, the processor can be implemented in one or more of the following units: an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a processor, a controller, a microcontroller, a microprocessor, other electronic units designed to implement the functions described herein, or a combination thereof. For software implementation, part or all of the processes of the embodiment can be completed by instructing the relevant hardware through a computer program. When implemented, the above program can be stored in a computer-readable storage medium or transmitted as one or more instructions or codes on a computer-readable storage medium. Computer-readable storage media include computer storage media and communication media, wherein the communication medium includes any medium that facilitates the transmission of a computer program from one place to another. The storage medium can be any available medium that can be accessed by a computer. Computer-readable storage media can include, but are not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a computer.

[0063] Finally, it should be noted that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An intelligent leakage warning flexible composite pipeline system, characterized in that: include: The composite pipe body comprises an inner lining layer, a reinforcement layer, an inner protective layer, at least one thermal insulation layer, a distributed temperature sensing element integrated in the outer wall of the protective layer, an optical cable wrapping layer and an outer protective layer arranged in sequence; An optical signal processing device, used to transmit an optical signal to the distributed temperature sensing element, receive reflected light and convert it into temperature data; A data processing unit, used to calculate the temperature distribution along the pipeline and the leakage position based on the temperature data, and trigger an abnormal alarm; The distributed temperature sensing element senses temperature changes through optical characteristics, and the optical signal processing device is communicatively connected with the data processing unit to realize data transmission.

2. The intelligent leakage warning flexible composite pipeline system according to claim 1 is characterized in that: The temperature along the pipeline is determined based on the power ratio of Stokes light to anti-Stokes light in combination with a preset heat conduction model; The leakage position is determined by a mapping relationship between the optical signal transmission time and the optical fiber path parameters.

3. The intelligent leakage warning flexible composite pipeline system according to claim 2 is characterized in that: The temperature along the pipeline is calculated by the following formula: in, It is the preset initial reference temperature, used as the basis for temperature calculation; It is a coefficient related to the heat conduction characteristics of the pipeline, which is used to reflect the heat conduction capacity of the pipeline material; It is the convection heat transfer coefficient, which is used to reflect the heat exchange efficiency between the pipeline and the surrounding environment or the internal fluid; It is the change in flow velocity of the fluid in the pipeline, which is used to reflect the influence of heat transfer and temperature distribution; For the temperature When , the optical power value of anti-Stokes light; For the temperature When , the optical power value of Stokes light; At the initial reference temperature When , the optical power value of anti-Stokes light; At the initial reference temperature The optical power value of Stokes light at .

4. The intelligent leakage warning flexible composite pipeline system according to claim 2 is characterized in that: The leakage position is calculated by the following formula: in, Sense the length of the optical fiber from the starting point of the optical fiber connected to the device to the leakage point; is the pitch of the sensing optical fiber wound on the insulation layer; is the outer diameter of the composite pipe body; is the thickness of the outer protective layer; It is the distance from the starting point of the optical fiber connected to the equipment to the end where the optical fiber enters the composite pipe body; is the propagation speed of light in the distributed temperature sensing element; is the time interval from the emission of the optical signal to the reception of the reflected optical signal; is the refractive index of the optical fiber.

5. The intelligent leakage warning flexible composite pipeline system according to claim 1 is characterized in that: The distributed temperature sensing element is a multi-core structure and is wound around the outside of the insulation layer at a preset angle, and achieves signal continuity through optical coupling technology; The reinforcement layer is made of high-strength material and is wound around the outside of the inner lining layer at a preset angle.

6. The intelligent leakage warning flexible composite pipeline system according to claim 1 is characterized in that: The composite pipe body is provided with a detachable joint, which includes a core sleeve and an outer sleeve connected in an inner buckle or threaded manner. The core sleeve and the outer sleeve seal the inner lining layer, the reinforcement layer and the protective layer through mechanical bite and sealing.

7. The intelligent leakage warning flexible composite pipeline system according to claim 1 is characterized in that: The composite pipe body is provided with an optical fiber joint, and the optical fiber joint realizes continuous signal transmission through hot-melt welding or optical coupler, and the outer layer of the optical fiber joint is an anti-corrosion coating.

8. The intelligent leakage warning flexible composite pipeline system according to claim 1 is characterized in that: The data processing unit uses a dynamic data correction algorithm to filter abnormal temperature fluctuations, and the filtering of abnormal temperature fluctuations specifically includes: reducing false alarms caused by environmental interference or sensor noise.

9. The intelligent leakage warning flexible composite pipeline system according to claim 8, characterized in that: The dynamic data correction algorithm is specifically: in, is the calculated abnormal data point The replacement data, is the sequence number of the abnormal data point, The offset variable.

10. An intelligent leakage warning flexible composite pipeline early warning method, applied to the intelligent leakage warning flexible composite pipeline system according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: S1: configuring a composite pipe body, wherein the composite pipe body comprises an inner lining layer, a reinforcement layer, an inner protective layer, at least one thermal insulation layer, and a distributed temperature sensing element integrated on an outer wall of the composite pipe; S2: transmitting a laser signal to a distributed temperature sensing element through an optical signal processing device; S3: collecting Stokes light and anti-Stokes light in the reflected light through an optical signal processing device and converting them into temperature data; S4: The data processing unit analyzes the temperature distribution based on the temperature data. If a temperature anomaly is detected, the temperature distribution along the pipeline and the leakage position are calculated, and an abnormality alarm is issued.

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