Shielded cable for signal transmission

Abstract

The utility model discloses a shielding cable for signal transmission, which comprises a conductor, and a first insulating layer, a first wrapping layer, a first shielding layer and a sheath layer which are coaxially arranged on the outer side of the conductor in sequence, a corrugated pipe is sleeved on the outer side of the sheath layer, and a plurality of supporting strips extending along the length direction of the sheath layer are arranged on the outer side surface of the sheath layer. The corrugated pipe comprises a plurality of supporting strips arranged at intervals in the circumferential direction, the supporting strips abut against the inner wall of the corrugated pipe to make contact with the inner wall of the corrugated pipe, so that a gap layer is formed between the adjacent supporting strips and the inner wall of the corrugated pipe, flame-retardant filler is arranged in the gap layer, and the surface of the outer side of the corrugated pipe is wrapped with a metal braid layer. According to the utility model, the cable has good anti-interference and electrical performance, the tolerance, stability and flame retardance of the cable in a high-temperature complex environment for a long time are improved, and the stability of the whole structure is improved, so that the precision and stability of a detection result are ensured.

Description

Technical Field

[0001] The utility model relates to a shielded cable for signal transmission, belonging to the technical field of nuclear power station detection. Background Art

[0002] Neutron detectors are one of the essential components of nuclear reactors. They are used to monitor the neutron injection rate of nuclear reactors to adjust the insertion depth of control rods and the concentration of moderators, so as to control the reactor power and ensure safe operation. High-temperature fission chambers are a type of in-core neutron detector, mainly consisting of probes, suspension devices, and secondary instruments. The probes and the signal transmission cables connected to the probes are the core components of high-temperature fission chambers, and their performance directly determines the detection performance of high-temperature fission chambers. Cables are easily damaged if they are in a nuclear reactor with high temperature and strong radiation for a long time. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a shielded cable for signal transmission, which has good anti-interference and electrical properties, and improves the cable's long-term resistance, stability and flame retardancy in high temperature and complex environments, thereby enhancing the stability of the overall structure and ensuring the accuracy and stability of the detection results.

[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is: a shielded cable for signal transmission, comprising: a conductor and a first insulating layer, a first wrapping layer, a first shielding layer, and a sheath layer which are coaxially arranged on the outside of the conductor in sequence, a corrugated tube is sleeved on the outside of the sheath layer, and a plurality of support bars extending along its length direction are arranged on the outer surface of the sheath layer, and a plurality of support bars arranged at intervals in the circumferential direction are each in pressure contact with the inner wall of the corrugated tube, thereby forming a gap layer between adjacent support bars and the inner wall of the corrugated tube, a flame-retardant filler is arranged in the gap layer, and a metal braided layer is coated on the outer surface of the corrugated tube.

[0005] The further improved scheme in the above technical scheme is as follows:

[0006] 1. In the above solution, the flame retardant filler is flame retardant glue, flame retardant powder or yarn impregnated with flame retardant liquid.

[0007] 2. In the above solution, the bellows is a stainless steel bellows, and the density of the bellows is not less than 27 bellows per 100 mm.

[0008] 3. In the above solution, the metal braided layer is woven from stainless steel wires, and the braiding density is not less than 90%.

[0009] 4. In the above solution, the sheath layer and the support strips on its outer surface are an integrally formed structure.

[0010] 5. In the above solution, the sheath layer is a radiation cross-linked polyolefin sheath layer.

[0011] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0012] The utility model is a shielded cable for signal transmission, and a corrugated tube is sleeved on the outer side of its sheath layer, and a plurality of support bars extending along the length direction are arranged on the outer surface of the sheath layer, and the plurality of support bars arranged at intervals in the circumferential direction are each pressed and contacted with the inner wall of the corrugated tube, so that a gap layer is formed between adjacent support bars and the inner wall of the corrugated tube, and a flame retardant filler is arranged in the gap layer. A metal braided layer is coated on the outer surface of the corrugated tube, which has good anti-interference and electrical properties, and improves the long-term resistance, stability and flame retardancy of the cable in a high temperature and complex environment, and can also improve the stability of the relative position between the outer corrugated tube and the inner sheath, and enhance the stability of the overall structure, thereby ensuring the accuracy and stability of the detection result. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Attached Figure 1 This is a schematic diagram of the structure of a shielded cable for signal transmission according to the utility model;

[0014] Attached Figure 2 The utility model is a partial structural schematic diagram of a shielded cable used for signal transmission.

[0015] In the above figures: 1, conductor; 3, first insulating layer; 4, second insulating layer; 5, first wrapping layer; 6, first shielding layer; 7, second wrapping layer; 8, third insulating layer; 9, third wrapping layer; 10, second shielding layer; 11, sheath layer; 12, corrugated tube; 13, metal braided layer; 14, support bar; 15, gap layer; 16, flame retardant filler. DETAILED DESCRIPTION

[0016] The present invention can be further understood through the specific embodiments given below, but they are not intended to limit the present invention.

[0017] Embodiment 1: A shielded cable for signal transmission, used for transmitting the working voltage and signal of the neutron detector of a nuclear power plant, comprising: a conductor 1 and a first insulating layer 3, a first wrapping layer 5, a first shielding layer 6, and a sheath layer 11 coaxially arranged in sequence on the outside of the conductor 1, a corrugated tube 12 is sleeved on the outside of the sheath layer 11, and a plurality of support bars 14 extending along the length direction are arranged on the outer surface of the sheath layer 11, and a plurality of support bars 14 arranged at intervals in the circumferential direction are each pressed against the inner wall of the corrugated tube 12, thereby forming a gap layer 15 between adjacent support bars 14 and the inner wall of the corrugated tube 12, and a flame retardant filler 16 is arranged in the gap layer 15, and a metal braided layer 13 is coated on the outer surface of the corrugated tube 12.

[0018] The flame retardant filler 16 is flame retardant rubber; the bellows 12 is an H-shaped 316L austenitic stainless steel bellows, and the density of the corrugations is not less than 27 corrugations per 100 mm;

[0019] The metal braided layer 13 is braided from 316L austenitic stainless steel wire, and the braiding density is not less than 90%;

[0020] The conductor 1 is a silver-plated copper conductor; the second wrapping layer 7, the third insulating layer 8 and the third wrapping layer 9 are arranged in sequence between the first shielding layer 6 and the sheath layer 11; the third insulating layer 8 is a double-layer co-extruded insulating layer of radiation cross-linked polyethylene and radiation cross-linked polyolefin; the semi-finished product after extrusion is irradiated and cross-linked by an electron accelerator; the first wrapping layer 5, the second wrapping layer 7 and the third wrapping layer 9 are all formed by overlapping wrapping of polyimide tapes, and the wrapping overlap rate is not less than 40%.

[0021] Embodiment 2: A shielded cable for signal transmission, comprising: a conductor 1 and a first insulating layer 3, a first wrapping layer 5, a first shielding layer 6, and a sheath layer 11 coaxially arranged on the outside of the conductor 1 in sequence, a corrugated tube 12 is sleeved on the outside of the sheath layer 11, and a plurality of support bars 14 extending along the length direction are arranged on the outer surface of the sheath layer 11, and a plurality of support bars 14 arranged at intervals in the circumferential direction are each pressed against the inner wall of the corrugated tube 12, thereby forming a gap layer 15 between adjacent support bars 14 and the inner wall of the corrugated tube 12, a flame retardant filler 16 is arranged in the gap layer 15, and a metal braided layer 13 is coated on the outer surface of the corrugated tube 12.

[0022] The flame retardant filler 16 is a yarn impregnated with a flame retardant liquid;

[0023] The above-mentioned sheath layer 11 and the support strip 14 on its outer surface are an integrally formed structure;

[0024] The above-mentioned sheath layer 11 is a radiation cross-linked polyolefin sheath layer, and the semi-finished product after extrusion is subjected to radiation cross-linking treatment by an electron accelerator;

[0025] The conductor 1 is a copper conductor; the first insulating layer 3 is a polyetheretherketone insulating layer, which is extruded and coated on the semi-finished product by a high-temperature extruder, and passed through a hot water cooling tank with a water temperature of 90°C to avoid too fast insulation cooling rate, and the insulating layer is required not to have crystallization phenomenon, and a second insulating layer 4 is arranged between the first insulating layer 3 and the first wrapping layer 5, and the second insulating layer 4 is a radiation cross-linked polyethylene insulating layer with an insulation eccentricity of ≤10%. After extrusion, the semi-finished product is irradiated and cross-linked by an electron accelerator;

[0026] The cable as a whole has good electrical properties, anti-electromagnetic interference and low noise characteristics, as well as the characteristics of flame retardancy, low smoke, halogen-free, flood-proof, and good bending flexibility. It can be used normally for 60 years under the condition of a long-term working temperature of 50°C, and can also withstand the radiation of γ-ray cumulative dose of 600kGy and the radiation of β-ray cumulative dose of 2100kGy.

[0027] The above-mentioned shielded cable used for signal transmission not only has good anti-interference and electrical properties, but also improves the long-term resistance, stability and flame retardancy of the cable in high temperature and complex environments. It can also improve the stability of the relative position between the outer corrugated tube and the inner sheath, and enhance the stability of the overall structure, thereby ensuring the accuracy and stability of the detection results.

[0028] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A shielded cable for signal transmission, comprising: A conductor (1) and a first insulating layer (3), a first wrapping layer (5), a first shielding layer (6), and a sheath layer (11) are coaxially arranged on the outside of the conductor (1), characterized in that a corrugated tube (12) is sleeved on the outside of the sheath layer (11), a plurality of support bars (14) extending along the length direction of the sheath layer (11) are arranged on the outer surface of the sheath layer (11), and a plurality of support bars (14) arranged at intervals in the circumferential direction are each pressed against the inner wall of the corrugated tube (12), thereby forming a gap layer (15) between adjacent support bars (14) and the inner wall of the corrugated tube (12), and a flame retardant filler (16) is arranged in the gap layer (15), and a metal braided layer (13) is coated on the outer surface of the corrugated tube (12).

2. The shielded cable for signal transmission according to claim 1, characterized in that: The flame retardant filler (16) is flame retardant glue, flame retardant powder or yarn impregnated with flame retardant liquid.

3. The shielded cable for signal transmission according to claim 1, characterized in that: The bellows (12) is a stainless steel bellows, and the density of the bellows is not less than 27 bellows per 100 mm.

4. The shielded cable for signal transmission according to claim 1, characterized in that: The metal braided layer (13) is braided from stainless steel wires, and the braiding density is not less than 90%.

5. The shielded cable for signal transmission according to claim 1, characterized in that: The sheath layer (11) and the support strip (14) on its outer surface are an integrally formed structure.

6. The shielded cable for signal transmission according to claim 1 or 5, characterized in that: The sheath layer (11) is a radiation cross-linked polyolefin sheath layer.

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