Composite optical cable for pipeline heat tracing and monitoring

Abstract

The utility model discloses a composite optical cable for pipeline heat tracing and monitoring, which comprises a sensing optical fiber and a heating wire, the sensing optical fiber is wrapped by a first inner sleeve, the heating wire is wrapped by a second inner sleeve, the second inner sleeve is sleeved with a stranded wire woven net, and the stranded wire woven net is wrapped by a second inner sleeve. The stranded wire woven net and the first inner sleeve are sleeved with an outer sheath pipe, and the sensing optical fiber and the heating wire are symmetrically distributed in the outer sheath pipe. According to the composite optical cable provided by the utility model, the heating wire and the sensing optical fiber are arranged in the sleeve, so that the composite optical cable can provide long-distance uniform heating under the condition of 220V commercial power, the power consumption is maintained at 10W / m, and the composite optical cable can be used as a heat tracing band, can also be used for pipeline leakage and safety monitoring, and realizes the functions of heat tracing and safety monitoring; on-line real-time detection is carried out through the sensing optical fibers for measuring temperature and vibration, manual inspection is not needed for safe operation of the pipe network, and an effective whole-line monitoring means is provided for leakage and safety monitoring of the urban pipe network.

Description

Technical Field

[0001] The utility model relates to the technical field of composite optical cables, in particular to a composite optical cable for pipeline heating and monitoring. Background Art

[0002] Urban underground pipelines refer to pipelines and their ancillary facilities for water supply, drainage, gas, heat, electricity, communications, radio and television, industry, etc. within the city. They are important infrastructure and "lifelines" to ensure the operation of the city. A large number of urban underground pipelines constitute the urban underground pipeline network. At present, my country is building a relatively complete urban underground pipeline system, so that the construction and management level of underground pipelines can adapt to the needs of economic and social development, and the emergency disaster prevention capacity has been greatly improved. The urban underground pipeline network safety monitoring system has become an urgent need. At present, the effective monitoring method is to use sensor optical fiber to monitor the underground pipeline network. Sensor optical fiber refers to an optical fiber that converts the physical quantity of non-optical signals into optical signals, transmits them through optical fiber perception, and finally converts them into the measured physical quantity, which is used to measure physical quantities such as temperature, pressure, displacement, speed, voltage, current and melt concentration. However, since the urban underground pipeline network is laid underground, the environment is harsh and complex, which brings huge challenges to manual inspections.

[0003] In order to monitor the leakage and safety of urban pipeline networks, we have designed a composite optical cable for pipeline heating and monitoring to solve the above problems. Utility Model Content

[0004] The purpose of the utility model is to solve the problem of lack of effective full-line monitoring means for urban pipe network leakage and safety monitoring in the prior art, and to propose a composite optical cable for pipe heating and monitoring, which can have both pipe heating and safety monitoring functions and meet the complex monitoring environment of urban underground pipe networks.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A composite optical cable for pipeline heating and monitoring comprises a sensing optical fiber and a heating wire, wherein the sensing optical fiber is externally covered by a first inner sleeve, and the heating wire is externally covered by a second inner sleeve, a twisted wire braided net is externally sheathed on the second inner sleeve, an outer sheath tube is externally sheathed on the twisted wire braided net and the first inner sleeve, and the sensing optical fiber and the heating wire are symmetrically distributed in the outer sheath tube.

[0007] According to a further preferred solution of the utility model, a third inner sleeve is provided between the sensing optical fiber and the first inner sleeve, the sensing optical fiber is passed through the third inner sleeve, the third inner sleeve is filled with petroleum jelly, and the outer surface of the third inner sleeve is in contact with the inner surface of the first inner sleeve.

[0008] According to a further preferred solution of the utility model, the heating wire is powered by 220V mains electricity, the heating power is maintained at 10W / m, and the uniform heating distance is one kilometer.

[0009] According to a further preferred embodiment of the present invention, the second inner sleeve is made of a fluorine-containing polymer, and the stranded wire mesh is made of a nickel-plated copper stranded wire mesh.

[0010] According to a further preferred solution of the utility model, the outer sheath tube is made of polyethylene.

[0011] According to a further preferred solution of the utility model, the number of the sensing optical fibers disposed in the third inner sleeve is not less than two, and each of the sensing optical fibers is symmetrically arranged along the central axis of the third inner sleeve.

[0012] Compared with the prior art, the beneficial effects of the utility model are as follows: taking into account the practical environment under the urban underground pipeline network, the composite optical cable proposed by the utility model arranges a heating conductor and a sensor optical fiber in the sheath. The composite optical cable can provide long-distance uniform heating under 220V AC power, and the power consumption is maintained at 10W / meter. It can be used as a heating belt and can also be used for pipeline leakage and safety monitoring, realizing the functions of heating and safety monitoring. It can heat the pipelines of the underground pipeline network, and the temperature and vibration changes generated when the pipeline leaks can be detected online in real time through sensor optical fibers for measuring temperature and vibration. For the safe operation of the pipeline network, there is no need for manual inspections, and an effective safety line monitoring means is provided for urban pipeline network leakage and safety monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a three-dimensional structural schematic diagram of a composite optical cable for pipeline heating and monitoring proposed by the utility model;

[0014] Figure 2 The utility model is a schematic diagram of the cross-sectional structure of a composite optical cable for pipeline heating and monitoring.

[0015] The numbers in the figure are: 1. Sensing optical fiber; 2. Heating wire; 3. First inner sleeve; 4. Second inner sleeve; 5. Twisted wire mesh; 6. Outer sheath; 7. Third inner sleeve; 8. Petroleum jelly. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0017] The composite optical cable for pipeline heating and monitoring proposed in this embodiment is a composite optical cable with two functions of heating and monitoring superimposed on each other. The composite optical cable mainly includes a sensing optical fiber 1 and a heating conductor 2.

[0018] The sensing optical fiber 1 in this embodiment can adopt photonic crystal fiber (PCF), which is a new type of three-dimensional Bragg grating optical fiber, which is composed of glass fiber containing small air holes. Because it can confine light in the hollow core, this confinement characteristic is not possessed by traditional optical fibers, and is particularly suitable for nonlinear optical devices that transmit high energy. According to the frequency offset of different scattered signals, photonic crystal fiber can be used to measure temperature and strain simultaneously through Brillouin scattering sensing. Monitor the temperature and pressure changes of the urban underground pipeline network, thereby realizing leakage and safety monitoring of the urban pipeline network.

[0019] The heating wire 2 is a high-temperature resistant heating wire, through which a heating source is provided. The heating wire 2 is powered by 220V AC power. The heating power of the heating wire 2 is maintained at 10W / m, and the uniform heating distance is one kilometer. The optical fiber temperature can be maintained at 40 to 60 degrees Celsius. Through heat tracing, the pipes of the underground pipeline network can be heated. The temperature and vibration changes generated when the pipeline leaks can be detected online in real time through the sensing optical fiber 1 for measuring temperature and vibration.

[0020] like Figure 1 and 2 As shown, the composite optical cable structure of this embodiment is introduced and explained. The outside of the sensing optical fiber 1 is covered by the first inner sleeve 3, and the outside of the heating wire 2 is covered by the second inner sleeve 4. A twisted wire mesh 5 is sheathed on the outside of the second inner sleeve 4, and an outer sheath tube 6 is sheathed on the outside of the twisted wire mesh 5 and the first inner sleeve 3. The sensing optical fiber 1 and the heating wire 2 are symmetrically distributed in the outer sheath tube 6.

[0021] It is worth mentioning that a third inner sleeve 7 is provided between the sensing optical fiber 1 and the first inner sleeve 3, the sensing optical fiber 1 is inserted into the third inner sleeve 7, and the number of sensing optical fibers 1 provided in the third inner sleeve 7 is not less than two ( Figure 1 and Figure 2 The number shown in the figure is two), each sensing optical fiber 1 is symmetrically arranged along the central axis of the third inner sleeve 7. The third inner sleeve 7 is filled with petroleum jelly 8, and the outer surface of the third inner sleeve 7 is attached to the inner surface of the first inner sleeve 3.

[0022] The petroleum jelly 8 is a flexible colloidal substance, which is filled into the third inner sleeve 7 at room temperature. It has a wide applicable temperature range (-40°C to 100°C) and good comprehensive performance. After the petroleum jelly 8 is filled into the third inner sleeve 7, it can play a waterproof and buffering role for the sensing optical fiber 1, has excellent thixotropic properties, and moderate viscosity.

[0023] In this embodiment, the second inner sleeve 4 is made of fluorine-containing polymers. There are many types of fluorine-containing polymers, including ethylene-tetrafluoroethylene copolymer (ETFE), polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy resin (PFA), polychlorotrifluoroethylene (PCTFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), polyvinylidene fluoride (PVDF) and polyvinyl fluoride, etc. The second inner sleeve 4 can be made of any of the above fluorine-containing polymers through extrusion, injection molding and blow molding to form a sleeve structure.

[0024] The reason why fluoropolymer is used to make the second inner sleeve 4 is that fluoropolymer is a linear alkane polymer, and part or all of the hydrogen atoms in its molecular structure are replaced by fluorine. Fluoropolymer has very high chemical resistance, does not absorb moisture, has a very low friction coefficient, and has good weather resistance. These properties of fluoropolymer make it the preferred material for products such as heat-resistant cables, pipes, coating materials, and weather-resistant films.

[0025] In addition, the stranded wire mesh 5 in this embodiment is made of nickel-plated copper stranded wire mesh, which has the function of improving the tensile strength of the structure and shielding electromagnetic fields. The outer sheath tube 6 is a PE outer sheath tube made of polyethylene.

[0026] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A composite optical cable for pipeline heating and monitoring, characterized in that: The invention comprises a sensing optical fiber (1) and a heating wire (2), wherein the sensing optical fiber (1) is externally covered by a first inner sleeve (3), and the heating wire (2) is externally covered by a second inner sleeve (4), a twisted wire braided net (5) is externally sheathed on the second inner sleeve (4), an outer sheath tube (6) is externally sheathed on the twisted wire braided net (5) and the first inner sleeve (3), and the sensing optical fiber (1) and the heating wire (2) are symmetrically distributed in the outer sheath tube (6).

2. A composite optical cable for pipeline heating and monitoring according to claim 1, characterized in that: A third inner sleeve (7) is provided between the sensing optical fiber (1) and the first inner sleeve (3), the sensing optical fiber (1) is inserted into the third inner sleeve (7), the third inner sleeve (7) is filled with petroleum jelly (8), and the outer surface of the third inner sleeve (7) is attached to the inner surface of the first inner sleeve (3).

3. A composite optical cable for pipeline heating and monitoring according to claim 1, characterized in that: The heating wire (2) is powered by 220V mains electricity, its heating power is maintained at 10W / m, and the uniform heating distance is one kilometer.

4. A composite optical cable for pipeline heating and monitoring according to claim 1, characterized in that: The second inner sleeve (4) is made of a fluorine-containing polymer, and the stranded wire mesh (5) is made of a nickel-plated copper stranded wire mesh.

5. The composite optical cable for pipeline heating and monitoring according to claim 1, characterized in that: The outer protective sheath tube (6) is made of polyethylene.

6. A composite optical cable for pipeline heating and monitoring according to claim 2, characterized in that: The number of the sensing optical fibers (1) arranged in the third inner sleeve (7) is no less than two, and each sensing optical fiber (1) is symmetrically arranged along the central axis of the third inner sleeve (7).

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