A winding wire for a control rod drive mechanism in a nuclear power plant

Abstract

This invention relates to a high-temperature and radiation-resistant winding wire for a nuclear power plant control rod drive mechanism. The winding wire comprises a conductor and an insulating layer attached to the conductor. The insulating layer includes a first wrapping layer and a second wrapping layer sequentially wrapped around the conductor from the inside out. Both the first and second wrapping layers are made of alkali-free glass fiber. Because the insulating material used in this invention does not contain organic materials, it eliminates the defects of organic materials in high-temperature resistance, allowing the winding wire to exceed the 350°C temperature limit and maintain stable operation at 500°C for extended periods. Furthermore, the thickness of the entire insulating layer can be controlled to 0.20 mm or less on both sides, reducing the insulation thickness by 30% compared to existing technologies. This improves slot fill efficiency and significantly reduces the volume of the nuclear power plant control rod drive mechanism, meeting the needs of intensive development.

Description

Technical Field

[0001] This invention belongs to the field of special winding wire technology, specifically relating to a high-temperature and radiation-resistant winding wire for a control rod drive mechanism in a nuclear power plant. Background Technology

[0002] Nuclear power products have extremely high requirements for safety and stability, thus placing higher demands on their heat resistance. To address these ever-increasing requirements, a special high-temperature radiation-resistant winding wire is developed for the control rod drive mechanism of nuclear power plants. This winding wire can withstand long-term high temperatures of 500℃ and 5×10⁵ Gy gamma rays, and has a thin insulation thickness.

[0003] Chinese patent CN201110137875.2 discloses a high-temperature and radiation-resistant electromagnetic wire for nuclear power units, comprising a conductor and an insulating layer wrapped around the conductor. The conductor is a nickel-plated copper conductor with a nickel plating layer on its surface. The insulating layer includes a glass fiber cloth-reinforced silicone mica tape layer wrapped around the conductor and a glass fiber layer wrapped around the glass fiber cloth-reinforced silicone mica tape layer. Advantages: It has ideal high-temperature resistance, can operate stably for a long time at 260℃; after being irradiated with a gamma-ray dose of 5×10⁵ GY, its withstand voltage performance does not decrease after a withstand voltage test; it has excellent corona resistance characteristics, with a square wave pulse test voltage repetition frequency of 20KHz, a pulse peak voltage of ±5000V, a pulse voltage rise rate of not less than 2000V / μs, and a temperature of 120℃, the corona damage life is not less than 100 hours; it has good insulation properties, with a breakdown voltage of over 3800V. However, its temperature rating is only 260°C, which cannot meet the heat resistance requirements of electrical materials used in the control rod drive mechanism of future nuclear power plants. Furthermore, due to limitations in its insulation structure, the total insulation thickness exceeds 0.25 mm.

[0004] Furthermore, Chinese patent CN201611184911.X discloses a high-temperature resistant, radiation-resistant, and waterproof electromagnetic wire and its preparation method. The electromagnetic wire includes a conductor and, from the inside out, a glass fiber cloth-reinforced silicone mica tape layer, a first high-temperature resistant and radiation-resistant insulating varnish layer, glass fiber filaments, a second high-temperature resistant and radiation-resistant insulating varnish layer, and a waterproof adhesive layer, all wrapped around the conductor sequentially. It has a heat resistance rating of 350℃ and exhibits radiation resistance and water resistance. However, its temperature rating of only 350℃ cannot meet the heat resistance requirements of electrical materials used in future nuclear power plant control rod drive mechanisms. Moreover, due to limitations in its insulation structure, the total insulation thickness exceeds 0.25mm. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a winding wire for a control rod drive mechanism in a nuclear power plant, which has high temperature resistance and radiation resistance.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A high-temperature and radiation-resistant winding wire for a control rod drive mechanism in a nuclear power plant includes a conductor and an insulating layer attached to the conductor. The insulating layer includes a first wrapping layer and a second wrapping layer that are sequentially wrapped around the conductor from the inside out. Both the first wrapping layer and the second wrapping layer are made of alkali-free glass fiber.

[0008] Preferably, the alkali-free glass fiber of the first wrapping layer is 360 or 600 strands.

[0009] Preferably, the second wrapping layer contains 360 or 600 alkali-free glass fibers.

[0010] Preferably, the wrapping direction of the first wrapping layer is opposite to the wrapping direction of the second wrapping layer.

[0011] Preferably, the conductor surface is provided with a nickel plating layer.

[0012] Preferably, the thickness of the nickel plating layer on both sides is 0.010~0.015mm.

[0013] Preferably, the conductor has a copper content of 99.95% and a volume resistivity of ≤0.017960 Ω·mm. 2 / m, and the breaking elongation of the conductor is ≥28%.

[0014] Preferably, the conductor has a circular cross-section.

[0015] Preferably, the diameter of the conductor is 1.0 mm to 3.0 mm.

[0016] Preferably, the thickness of the first wrapping layer and the second wrapping layer is 0.08 mm to 0.10 mm.

[0017] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0018] The winding wire for the nuclear power plant control rod drive mechanism of the present invention has a first and second wrapping layer made of alkali-free glass fiber. Since the insulation material used does not contain organic materials, the defects of organic materials in high temperature resistance are eliminated, allowing the temperature resistance level of the winding wire to break through the 350-level limit and to be used stably for a long time at a high temperature of 500°C. In addition, the thickness of both sides of the entire insulation layer can be controlled to 0.20 mm or less, which is 30% less than the insulation thickness of the prior art. This is beneficial to improving slot fill factor and significantly reducing the volume of the nuclear power plant control rod drive mechanism, meeting the needs of intensive development. Attached Figure Description

[0019] Figure 1This is a schematic diagram of the cross-sectional structure of the winding wire of the present invention;

[0020] Wherein: 10, conductor; 100, nickel plating layer; 11, first wrapping layer; 12, second wrapping layer. Detailed Implementation

[0021] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown, a high-temperature and radiation-resistant winding wire for a control rod drive mechanism in a nuclear power plant includes a conductor 10 and an insulating layer attached to the conductor 10. The insulating layer includes a first wrapping layer 11 and a second wrapping layer 12 wrapped around the conductor 10 from the inside out. Both the first wrapping layer 11 and the second wrapping layer 12 are made of alkali-free glass fiber.

[0023] In this example, a nickel plating layer 100 is provided on the surface of conductor 10; the thickness of the nickel plating layer 100 on both sides is 0.010~0.015mm; the nickel plating treatment on the surface of conductor 10 can reduce the oxidation and deterioration of conductor 10 at high temperature, and also help to further extend the service life of winding wire.

[0024] Furthermore, the conductor 10 has a circular cross-section, a diameter of 1.0 mm to 3.0 mm, a copper content of 99.95%, a volume resistivity of ≤0.017960 Ω·mm² / m, and a break elongation of ≥28%.

[0025] Specifically, the first wrapping layer 11 has 360 or 600 alkali-free glass fibers; the second wrapping layer 12 has 360 or 600 alkali-free glass fibers, and the wrapping direction of the first wrapping layer 11 is opposite to that of the second wrapping layer 12. Furthermore, the thickness of both the first wrapping layer 11 and the second wrapping layer 12 is 0.08 mm to 0.10 mm; therefore, the total insulation layer thickness (both sides) is 0.16 mm to 0.20 mm.

[0026] Examples of the specific dimensions and specifications of the winding wires used in the nuclear power plant control rod drive mechanism of the present invention are as follows:

[0027] 1. Take a copper conductor 10 with a nickel plating layer 100, the diameter range is 1.450 mm to 1.465 mm, the thickness of the nickel plating layer 100 on both sides is 0.010 mm to 0.015 mm, and the content of the nickel plating layer 100 is about 3.2% to 4.8%; then wrap two layers (first wrapping layer 11 and second wrapping layer 12) of 600 strands of electrical alkali-free glass fiber in opposite directions, the total insulation thickness is 0.16 mm, the finished product size is ≤1.66 mm, and the finished product insulation resistance at 500V is ≥1000MΩ.

[0028] 2. Take a copper conductor 10 containing a nickel plating layer 100, with a diameter ranging from 2.59 mm to 2.616 mm. The nickel plating layer 100 has a thickness of 0.010 mm to 0.015 mm on both sides and a nickel plating layer 100 content of approximately 1.8% to 2.7%. Then, continuously wrap two layers (first wrapping layer 11 and second wrapping layer 12) of 360 strands of alkali-free electrical glass fiber in opposite directions. The final product has an external dimension ≤ 2.80 mm and a 500V insulation resistance ≥ 1000 MΩ.

[0029] In summary, the winding wire for the nuclear power plant control rod drive mechanism of the present invention has both the first and second wrapping layers made of alkali-free glass fiber. Since the insulating material used does not contain organic materials, the defects of organic materials in high temperature resistance are eliminated, allowing the temperature resistance level of the winding wire to break through the 350-level limit and to be used stably for a long time at a high temperature of 500°C. In addition, the thickness of both sides of the entire insulation layer can be controlled to 0.20 mm or less, which is 30% less than the insulation thickness of the prior art. This is beneficial to improving slot fill factor and significantly reducing the volume of the nuclear power plant control rod drive mechanism, meeting the needs of intensive development.

[0030] The present invention has been described in detail above, with the aim of enabling those skilled in the art to understand and implement the invention. However, this description should not be construed as limiting the scope of protection of the invention. Furthermore, the invention is not limited to the embodiments described above. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be included within the scope of protection of the invention.

Claims

1. A high-temperature and radiation-resistant winding wire for a control rod drive mechanism in a nuclear power plant, comprising: A conductor, wherein the conductor has a circular cross-section and a nickel plating layer is disposed on the surface of the conductor; An insulating layer is attached to the conductor, and the insulating layer includes a first wrapping layer and a second wrapping layer that are sequentially wrapped around the conductor from the inside to the outside; Its features are: The conductor has a diameter of 1.0 mm to 3.0 mm, and the nickel plating layer has a bilateral thickness of 0.010 mm to 0.015 mm. Both the first and second wrapping layers are made of alkali-free glass fiber, with 360 or 600 strands of alkali-free glass fiber in each layer. The wrapping direction of the first wrapping layer is opposite to that of the second wrapping layer. The thickness of both the first and second wrapping layers is 0.08 mm to 0.10 mm, resulting in a total bilateral thickness of 0.16 mm to 0.20 mm for the insulation layer.

2. The high-temperature and radiation-resistant winding wire for the control rod drive mechanism of a nuclear power plant according to claim 1, characterized in that: The conductor has a copper content of 99.95%, a volume resistivity of ≤0.017960Ω·mm² / m, and an elongation at break of ≥28%.

3. The high-temperature and radiation-resistant winding wire for the control rod drive mechanism of a nuclear power plant according to claim 1, characterized in that: The diameter of the conductor ranges from 1.450 mm to 1.465 mm, and the content of the nickel plating layer is from 3.2% to 4.8%.

4. The high-temperature and radiation-resistant winding wire for the control rod drive mechanism of a nuclear power plant according to claim 1, characterized in that: The diameter of the conductor ranges from 2.59 mm to 2.616 mm, and the content of the nickel plating layer is from 1.8% to 2.7%.

Images