Penetration piece cable for nuclear power station

Abstract

The utility model relates to the technical field of cables for nuclear power stations, and discloses a penetration assembly cable for a nuclear power station. The cable comprises a cable core, a filling layer (4) and an outer sheath (5), the cable core is formed by twisting 1-4 wire cores; the wire core comprises a conductor (1), a conductor insulating layer (2) and a conductor wrapping layer (3) which are sequentially arranged from inside to outside. After being connected with an electrical connector, the cable is applied to instrument control equipment connection in a severe accident environment of a nuclear power station, and is used for transmitting logic quantity signals and analog quantity signals. The cable disclosed by the utility model is reasonable in structural arrangement, can continuously work for 60 years in a high-temperature environment of 150 DEG C, and can tolerate 375kGy irradiation dose (gamma ray). And the key electrical performance and the physical and mechanical performance of the cable can be ensured within the service life.

Description

Technical Field

[0001] This utility model relates to the field of cable technology, specifically to a through-type cable for nuclear power plants. Background Technology

[0002] When a serious accident occurs at a nuclear power plant, the temperature and pressure inside the containment will rise rapidly, and there may be a risk of explosion, which may cause vibrations such as wall cracking and collapse. Therefore, the stable operation of the instrumentation and control equipment inside the containment can help operators understand the real-time situation so that they can take appropriate actions to prevent the situation from deteriorating. At this time, the cables connecting the instrumentation and control equipment through electrical penetrations play a crucial role.

[0003] At present, almost all wires and cables used in nuclear power plants are produced domestically. However, cables for some key equipment in nuclear power plants still rely on imports. Domestic cables cannot yet meet the environmental and performance requirements of nuclear power plants, especially through-type cables for small-diameter nuclear power plants.

[0004] Nuclear power plant through-type cables require high outer diameter and good sealing connection with cable joints. This type of cable product structure is very rare for domestic cable manufacturers.

[0005] Prior art, application number 200820217304.3, discloses an electrical penetration cable, which includes a cable core and a tubular insulation layer. However, the single-layer polyetheretherketone (PEEK) insulation structure cannot effectively protect the penetration cable from normal operation under severe accident conditions, posing a safety hazard. Summary of the Invention

[0006] The purpose of this utility model is to provide a through-type cable for nuclear power plants, based on the above-mentioned technical problems.

[0007] To achieve the above objectives, the first aspect of this utility model provides a through-type cable for nuclear power plants, the cable comprising: a cable core, a filling layer 4, and an outer sheath 5; the cable core is formed by twisting together 1 to 4 wire cores; the wire core includes a conductor 1, a conductor insulation layer 2, and a conductor wrapping layer 3 arranged sequentially from the inside out.

[0008] The cable provided by this utility model has at least the following beneficial effects:

[0009] (1) The cable provided by this utility model uses multiple tin-plated copper wires stranded together as conductors, thus having better oxidation resistance.

[0010] (2) The cable provided by this utility model uses polyether ether ketone (PEEK) as the insulation layer, which reduces the thickness of the insulation layer while meeting the electrical insulation performance of the cable, thereby reducing the overall outer diameter of the cable and meeting the small outer diameter requirement for the through-hole component.

[0011] (3) The cable provided by this utility model uses polyimide tape as the insulating high-temperature resistant wrapping layer, which effectively ensures that the various performance indicators of the insulated core meet the requirements under high temperature conditions, and also improves the overall performance of the cable.

[0012] (4) The cable provided by this utility model has increased the overall shock resistance of the cable by the stainless steel outer sheath, the silicone rubber filling layer plays a buffering role, the polyether ether ketone has high stress resistance and impact resistance, and the cable has good mechanical properties in each layer structure, which can ensure the normal transmission of signals under vibration or working conditions.

[0013] (5) The cable provided by this utility model uses 304L stainless steel as the outer sheath, which facilitates connection with 316L stainless steel connectors with ceramic bushings.

[0014] (6) All components of the cable provided by this utility model are low-smoke halogen-free flame-retardant materials, which can well meet the requirements of nuclear power plants for low-smoke halogen-free flame-retardant cables. Attached Figure Description

[0015] Figure 1 This is a cross-sectional view of the through-type cable for nuclear power plants described in this utility model.

[0016] Explanation of reference numerals in the attached figures

[0017] 1. Conductor 2. Conductor insulation layer

[0018] 3. Conductor wrapping layer 4. Filler layer

[0019] 5. Outer sheath Detailed Implementation

[0020] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0021] This utility model provides a through-type cable for nuclear power plants. The cable includes: a cable core, a filling layer 4, and an outer sheath 5. The cable core is formed by twisting 1 to 4 wire cores together. The wire core includes a conductor 1, a conductor insulation layer 2, and a conductor wrapping layer arranged sequentially from the inside to the outside.

[0022] To ensure the continuity of electrical and signal connections between the equipment inside and outside the containment structure and the power supply, and to maintain electrical and signal continuity between the interior and exterior of the containment, the cable core preferably has 1 to 4 conductors with a cross-sectional area of ​​0.5 to 6 mm². 2 .

[0023] In this invention, the polyetheretherketone (PEEK) wire core possesses excellent radiation resistance and electrical properties, as well as excellent flame retardant properties.

[0024] To prevent conductor 1 from oxidizing at high temperatures, in the cable, conductor 1 is composed of 7 tinned copper wires with a diameter of 0.43mm, twisted in a "1+7" structure, with a twist pitch of 8 to 12 times, the outermost twisting direction being to the left, and an outer diameter of ≤1.29mm; or, conductor 1 is composed of 30 tinned copper wires with a diameter of 0.2mm, twisted with a twist pitch of 8 to 12 times, the outermost twisting direction being to the left, and an outer diameter of ≤1.29mm.

[0025] In order to improve the radiation resistance of the cable core and ensure the electrical insulation of the core, the conductor insulation layer 2 in the cable is made of polyetheretherketone (PEEK), and the PEEK is extruded on the outside of the conductor 1. The extrusion temperature of the PEEK is 350-390°C and the thickness is 0.5-0.7 mm.

[0026] To improve the insulation and high-temperature resistance of the cable core, the conductor wrapping layer 3 in the cable is made of polyimide tape, and the polyimide tape is wrapped around the outside of the conductor insulation layer 2; and the wrapping thickness of the polyimide tape is 0.04-0.06 mm, and the wrapping overlap rate of the polyimide tape is ≥15%, preferably 15-25%.

[0027] In order to fill the cable core to make the cable core round and improve the overall flame retardant and radiation resistance of the cable, the filling layer 4 in the cable is made of flame retardant, radiation resistant and high temperature resistant silicone rubber by extrusion, and the extrusion thickness of the flame retardant, radiation resistant and high temperature resistant silicone rubber is 0.8 to 1.2 mm.

[0028] To protect the cable core and facilitate connection to low-voltage electrical connectors via threads or fasteners, the outer sheath 5 of the cable is made by wrapping a 0.8mm thick 304L stainless steel plate around the outer layer of the filling layer 4 using a longitudinal wrapping machine, with the gaps welded by argon arc welding.

[0029] To ensure a reduction in the overall outer diameter of the cable, multiple conductors are stranded together. In this cable, the stranding pitch of the stranded conductors is ≤20 × the diameter of the conductor.

[0030] See Figure 1 In this embodiment, the cable has four wire cores.

[0031] In this embodiment, conductor 1 is composed of seven tin-plated copper wires with a diameter of 0.43 mm, twisted together in a "1+7" structure, with a twist pitch of 8 to 12 times. The outermost layer is twisted in a left-hand direction, and the outer diameter is required to be ≤1.29 mm. Under these conditions, the resulting conductor 1 has better oxidation resistance and flexibility.

[0032] In this embodiment, the conductor insulation layer 2 is made of polyetheretherketone (PEEK), and the PEEK is extruded onto the outside of the conductor 1; the extrusion temperature of the PEEK is 350–390°C, and the thickness is 0.5 mm.

[0033] In this embodiment, the conductor wrapping layer 3 is made of polyimide tape, and the polyimide tape is wrapped around the outside of the conductor insulation layer 2; the wrapping thickness of the polyimide tape is 0.04 mm, and the wrapping overlap rate of the polyimide tape is preferably 15-25%.

[0034] In this embodiment, the filler layer 4 is made of flame-retardant, radiation-resistant, and high-temperature resistant silicone rubber extruded by extrusion, and the extrusion thickness of the flame-retardant, radiation-resistant, and high-temperature resistant silicone rubber is 0.8 mm.

[0035] In this embodiment, the outer sheath 5 is made by wrapping a 0.8mm thick 304L stainless steel plate around the outer layer of the filling layer 4 using a longitudinal wrapping machine, and the gaps are welded by argon arc welding.

[0036] In this embodiment, the twisting pitch of the stranded wire cores to form the cable core is ≤20 × cable core diameter.

[0037] The cable obtained through the above technical solution, after being connected to an electrical connector, is applied to the connection of instrumentation and control equipment in nuclear power plants under severe accident conditions, for transmitting logic and analog signals. The cable structure of this invention is rationally designed, allowing it to operate continuously for 60 years at a high temperature of 150°C and withstand an irradiation dose of 375 kGy (gamma rays). Throughout its lifespan, the cable's key electrical and physical-mechanical properties are guaranteed.

[0038] The preferred embodiments of this utility model have been described in detail above; however, this utility model is not limited thereto. Within the scope of the technical concept of this utility model, various simple modifications can be made to the technical solution of this utility model, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed by this utility model and are all within the protection scope of this utility model.

Claims

1. A raceway cable for a nuclear power plant, characterized in that, The cable comprises a cable core, a filling layer (4), and an outer sheath (5); the cable core is twisted by 1-4 wire cores; the wire core comprises, from inside to outside, a conductor (1), a conductor insulation layer (2), and a conductor wrapping layer (3).

2. The cable of claim 1, wherein, In the cable, the conductor (1) is 7 tin-plated copper wires with a diameter of 0.43 mm, twisted into a "1+7" structure with a twisting pitch of 8-12 times, and the outermost layer is twisted in a left direction with an outer diameter ≤1.29 mm. And / or, the conductor (1) is twisted by 30 tin-plated copper wires with a diameter of 0.2 mm, with a twisting pitch of 8-12 times, and the outermost layer is twisted in a left direction with an outer diameter ≤1.29 mm.

3. The electrical cable according to claim 1 or 2, characterized in that, In the cable, the conductor insulation layer (2) is made of polyether ether ketone, and the polyether ether ketone is extruded on the outside of the conductor (1).

4. The cable of claim 3, wherein, In the cable, the temperature for extruding the polyether ether ketone is 350-390°C, and the thickness is 0.5-0.7 mm.

5. The cable according to claim 1 or 2, characterized in that, In the cable, the conductor wrapping layer (3) is made of polyimide tape, and the polyimide tape is wrapped on the outside of the conductor insulation layer (2).

6. The cable of claim 5, wherein, In the cable, the wrapping thickness of the polyimide tape is 0.04-0.06 mm, and the wrapping overlap rate of the polyimide tape is ≥15%, and the wrapping overlap rate is 15-25%.

7. The cable according to claim 1 or 2, characterized in that In the cable, the filling layer (4) is composed of extruded flame-retardant radiation-resistant high-temperature-resistant silicone rubber, and the extrusion thickness of the flame-retardant radiation-resistant high-temperature-resistant silicone rubber is 0.8-1.2 mm.

8. The cable according to claim 1 or 2, characterized in that In the cable, the outer sheath (5) is wrapped with a 304L stainless steel strip with a thickness of 0.8 mm outside the filling layer (4) using a longitudinal wrapping machine, and the gaps are welded by argon arc welding.

9. The cable according to claim 1 or 2, characterized in that In the cable, the twisting pitch of the wire core twisted into the cable core is ≤20×cable core diameter.

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