Polypropylene insulated buried cable for airport navigation-aid lighting system

Abstract

The utility model discloses a polypropylene insulation buried cable for an airport navigation-aid lighting system. The buried cable is composed of a conductor, and a conductor shielding layer, an insulation layer, an insulation shielding layer, a metal shielding layer, a waterproof layer and a sheath layer which are sequentially arranged outside the conductor from inside to outside. The conductor shielding layer, the insulating layer and the insulation shielding layer are respectively of a polypropylene material structure, and the conductor shielding layer, the insulating layer and the insulation shielding layer are of a horizontal three-layer co-extrusion structure; and the water-blocking layer is of at least one layer of overlapped wrapping structure of a non-conductive water-blocking tape. The water-blocking flexible control cable gives consideration to both water-blocking performance and flexible performance, and has good adaptability and safety in a complex airport working condition environment.

Description

Technical Field

[0001] The utility model relates to a cable, in particular to a polypropylene insulated buried cable used for an airport navigation lighting system. Background Art

[0002] The airport navigation lighting system is a necessary visual aid to ensure the normal takeoff, landing and taxiing of aircraft at the airport. It is particularly important at night, in low visibility or under other complex weather conditions.

[0003] The cables used in the airport navigation lighting system are key facilities for providing power transmission for the navigation lights on both sides of the airport runway. The cables used in the airport navigation lighting system are currently produced in accordance with the industry standard MH / T 6049-2020, with a simple structure and no other special performance requirements. However, the cables used in the airport navigation lighting system are directly buried under the lawns on both sides of the airport runway, and are not laid in pipes, which makes the cables used in the airport navigation lighting system greatly affected by the outside world. The use environment may encounter special working conditions such as long-term soaking in water, insect bites, high temperature or cold weather. Long-term exposure to the above special working conditions may increase the resistance of the insulation layer or become unstable, posing hidden dangers to the entire navigation lighting system. Furthermore, the cables used in the airport navigation lighting system need to be flexible and changeable along with the laid airport runway, and are in a humid environment under the lawn for a long time. Therefore, the cables used in the airport navigation lighting system have very high technical requirements for their own softness and waterproofness.

[0004] At present, in order to cope with the special working conditions of cables used in airport navigation lighting systems, polyolefin materials with high water resistance and insulation properties are usually used to form conductor shielding layers, insulation layers and insulation shielding layers in a horizontal three-layer co-extrusion structure, relying on the characteristics of the material itself and the horizontal three-layer co-extrusion process for waterproofing. For example, the Chinese patent document discloses the name "flame-retardant and environmentally friendly buried cable for airport navigation lighting system", publication number CN 208538551 U, publication date February 22, 2019, and the name "new type of cable for airport navigation lights", publication number CN117558494 A, publication date February 13, 2024. Although the cables of the above technical measures have certain waterproof properties, they do not have other physical water-blocking structures, which makes their water-blocking properties poor when they are in service in the airport navigation lighting system, and they cannot be reliably and long-term in service, which easily brings safety hazards to the entire navigation lighting system.

[0005] In order to improve the water-blocking performance of cables for airport navigation lights, there are technologies that use polyolefin materials as the basis and add other physical water-blocking structures in the disclosed prior art, such as the technology disclosed in the Chinese patent document entitled "an underground cable for airport navigation lighting system", publication number CN 215770581 U, and publication date February 8, 2022. However, this technology uses a single-sided aluminum-plastic composite tape longitudinally wrapped structure to form a physical water-blocking structure outside the metal shielding layer. Although it has excellent waterproof effect, it has poor softness and bendability, which is not conducive to flexible underground laying in the working environment of the airport.

[0006] Therefore, in view of the particularity of the above-mentioned airport working environment, it is necessary to design an underground cable for the airport navigation lighting system that effectively takes into account both water-blocking performance and soft performance. Utility Model Content

[0007] The technical purpose of the utility model is to provide a polyolefin insulated buried cable for an airport navigation lighting system that effectively takes into account both water-blocking performance and softness in view of the particularities of the airport working environment and the navigation lighting system and the deficiencies of the prior art.

[0008] The technical purpose of the utility model is achieved by the following technical scheme: a polypropylene insulated buried cable for an airport navigation lighting system, the buried cable is composed of a conductor and a conductor shielding layer, an insulating layer, an insulating shielding layer, a metal shielding layer, a water-blocking layer and a sheath layer arranged in sequence from the inside to the outside of the conductor;

[0009] The conductor shielding layer, the insulating layer and the insulating shielding layer are respectively made of polypropylene material, and the conductor shielding layer, the insulating layer and the insulating shielding layer are horizontal three-layer co-extrusion structures;

[0010] The water-blocking layer is at least one layer of overlapping wrapped structure of non-conductive water-blocking tape.

[0011] The polypropylene insulated buried cable for the airport navigation lighting system of the above-mentioned technical measures adopts the traditional horizontal three-layer co-extrusion structure of the conductor shielding layer, the insulating layer and the insulating shielding layer, and adds a physical waterproof structure of the overlapping wrapping structure of the non-conductive water tape. It has good waterproof performance and does not affect the softness of the formed cable. It can be well applied to the underground working environment of the airport navigation lighting system power supply.

[0012] The conductor shielding layer is a polypropylene shielding material structure, and the extrusion thickness of the conductor shielding layer is 0.50-0.60 mm.

[0013] The insulating layer is a polypropylene insulating structure, and the extruded thickness of the insulating layer is 2.8-3.2 mm.

[0014] The insulating shielding layer is a polypropylene shielding material structure, and the extruded thickness of the insulating shielding layer is 0.56-0.60 mm.

[0015] The above technical measures adopt an insulating layer of a polypropylene insulation structure, and a conductor shielding layer and an insulating shielding layer of a polypropylene shielding material structure, and utilize the high density and high crystallinity of polypropylene to achieve the technical goals of good waterproof performance and high softness.

[0016] The conductor is a twisted structure of multiple copper strands, and the twisted gaps of the copper strands are filled with water-blocking yarn or water-blocking powder;

[0017] Each copper strand is formed by twisting together a number of copper wires with a single wire diameter of 1.04 to 1.06 mm.

[0018] The copper strands of the conductor have a twisted pitch diameter ratio of 18 to 22 times;

[0019] The diameter of the conductor is in the range of 3.1 to 3.2 mm.

[0020] The conductor of the above technical measures has excellent flexibility. At the same time, by filling water-blocking yarn or water-blocking powder in the gap of the conductor formed by twisting multiple copper strands, it has excellent water-blocking performance, that is, it further improves the waterproof performance and flexibility of the cable without hindering the power supply performance of the cable.

[0021] The metal shielding layer is a single-layer overlapping wrapping structure of copper tape, and the overlapping wrapping coverage rate is ≥15%. This technical measure has a good electromagnetic shielding effect, effectively adapts to the airport working environment, and is safe and stable.

[0022] The thickness of the non-conductive water-blocking tape of the water-blocking layer is 0.25 to 0.35 mm;

[0023] The overlapping wrapping rate of the non-conductive water-blocking tape of the water-blocking layer is 25-50%.

[0024] The above technical measures adopt a non-conductive waterproof tape with an overlapping wrapping rate of 25-50% and a thickness of 0.25-0.35 mm, which has the technical characteristics of good waterproof effect and high softness.

[0025] The sheath layer is a sheath material structure that is rat-proof and ant-proof. This technical measure can effectively prevent ants and rats from gnawing in an underground environment.

[0026] The beneficial technical effect of the utility model is that the utility model effectively takes into account both water-blocking performance and softness, and has good adaptability and safety in complex airport working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the utility model.

[0028] The meaning of the codes in the figure are: 1—conductor; 2—conductor shielding layer; 3—insulating layer; 4—insulating shielding layer; 5—metal shielding layer; 6—water-blocking layer; 7—sheath layer. DETAILED DESCRIPTION

[0029] The utility model relates to a cable, specifically a polypropylene insulated buried cable for an airport navigation lighting system. Figure 1 The technical solution of the utility model is clearly and in detail explained.

[0030] Example 1

[0031] See also Figure 1 As shown, a polypropylene insulated buried cable for an airport navigation lighting system is composed of a conductor 1, and a conductor shielding layer 2, an insulating layer 3, an insulating shielding layer 4, a metal shielding layer 5, a water-blocking layer 6 and a sheath layer 7 arranged in sequence from the inside to the outside of the conductor 1.

[0032] Specifically, the diameter of the conductor 1 is about 3.1 mm, and it is a twisted structure of multiple copper strands, with a twisted pitch-diameter ratio of about 18 times. The twisted gaps of these copper strands are filled with water-blocking yarn. The aforementioned copper strands are twisted together by twisting a number of copper wires with a single wire diameter of about 1.04 mm.

[0033] The conductor shielding layer 2 is an extruded structure of polypropylene shielding material on the outer wall of the conductor 1, and the thickness of the extruded structure is about 0.5 mm.

[0034] The insulating layer 3 is an extruded structure of polypropylene insulating material on the outer wall of the conductor shielding layer 2, and the thickness of the extruded structure is about 2.8 mm.

[0035] The insulating shielding layer 4 is an extruded structure of polypropylene shielding material on the outer wall of the above-mentioned insulating layer 3, and the thickness of the extruded structure is about 0.56 mm.

[0036] The conductor shielding layer 2, the insulating layer 3 and the insulating shielding layer 4 are a horizontal three-layer co-extrusion structure.

[0037] The metal shielding layer 5 is a single-layer overlapping structure of thin copper tape wrapped around the outer wall of the insulating shielding layer 4, and the overlapping coverage rate is about 15%.

[0038] The water-blocking layer 6 is a non-conductive water-blocking tape with a thickness of about 0.25 mm, and is a two-layer overlapping wrapping structure on the outer wall of the metal shielding layer 5, and the overlap rate of each layer of the overlapping wrapping structure is about 25%.

[0039] The sheath layer 7 is an extruded structure of an elastomer sheath material that is anti-rat and anti-ant on the outer wall of the water-blocking layer 6 .

[0040] Example 2

[0041] See also Figure 1 As shown, a polypropylene insulated buried cable for an airport navigation lighting system is composed of a conductor 1, and a conductor shielding layer 2, an insulating layer 3, an insulating shielding layer 4, a metal shielding layer 5, a water-blocking layer 6 and a sheath layer 7 arranged in sequence from the inside to the outside of the conductor 1.

[0042] Specifically, the diameter of conductor 1 is about 3.15 mm, and it is a twisted structure of multiple copper strands, with a twisted pitch-diameter ratio of about 20 times. The twisted gaps of these copper strands are filled with water-blocking powder. The aforementioned copper strands are twisted together by twisting a number of copper wires with a single wire diameter of about 1.05 mm.

[0043] The conductor shielding layer 2 is an extruded structure of polypropylene shielding material on the outer wall of the conductor 1, and the thickness of the extruded structure is about 0.55 mm.

[0044] The insulating layer 3 is an extruded structure of polypropylene insulating material on the outer wall of the conductor shielding layer 2, and the thickness of the extruded structure is about 3.0 mm.

[0045] The insulating shielding layer 4 is an extruded structure of polypropylene shielding material on the outer wall of the above-mentioned insulating layer 3, and the thickness of the extruded structure is about 0.58 mm.

[0046] The conductor shielding layer 2, the insulating layer 3 and the insulating shielding layer 4 are a horizontal three-layer co-extrusion structure.

[0047] The metal shielding layer 5 is a single-layer overlapping structure of thin copper tape wrapped around the outer wall of the insulating shielding layer 4, and the overlapping coverage rate is about 20%.

[0048] The water-blocking layer 6 is a non-conductive water-blocking tape with a thickness of about 0.3 mm, and is an overlapping wrapping structure on the outer wall of the metal shielding layer 5 . The overlap rate of each overlapping wrapping structure is about 37.5%.

[0049] The sheath layer 7 is an extruded structure of an elastomer sheath material that is anti-rat and anti-ant on the outer wall of the water-blocking layer 6 .

[0050] Example 3

[0051] See also Figure 1 As shown, a polypropylene insulated buried cable for an airport navigation lighting system is composed of a conductor 1, and a conductor shielding layer 2, an insulating layer 3, an insulating shielding layer 4, a metal shielding layer 5, a water-blocking layer 6 and a sheath layer 7 arranged in sequence from the inside to the outside of the conductor 1.

[0052] Specifically, the diameter of the conductor 1 is about 3.2 mm, and it is a twisted structure of multiple copper strands, with a twisted pitch-diameter ratio of about 22 times. The twisted gaps of these copper strands are filled with water-blocking powder. The aforementioned copper strands are twisted together by twisting a number of copper wires with a single wire diameter of about 1.06 mm.

[0053] The conductor shielding layer 2 is an extruded structure of polypropylene shielding material on the outer wall of the conductor 1, and the thickness of the extruded structure is about 0.6 mm.

[0054] The insulating layer 3 is an extruded structure of polypropylene insulating material on the outer wall of the conductor shielding layer 2, and the thickness of the extruded structure is about 3.2 mm.

[0055] The insulating shielding layer 4 is an extruded structure of polypropylene shielding material on the outer wall of the above-mentioned insulating layer 3, and the thickness of the extruded structure is about 0.6 mm.

[0056] The conductor shielding layer 2, the insulating layer 3 and the insulating shielding layer 4 are a horizontal three-layer co-extrusion structure.

[0057] The metal shielding layer 5 is a single-layer overlapping structure of thin copper tape wrapped around the outer wall of the insulating shielding layer 4, and the overlapping coverage rate is about 25%.

[0058] The water-blocking layer 6 is a non-conductive water-blocking tape with a thickness of about 0.35 mm, and has a three-layer overlapping wrapping structure on the outer wall of the metal shielding layer 5, and the overlap rate of each layer of the overlapping wrapping structure is about 50%.

[0059] The sheath layer 7 is an extruded structure of an elastomer sheath material that is anti-rat and anti-ant on the outer wall of the water-blocking layer 6 .

[0060] The above specific technical solutions are only used to illustrate the present invention, rather than to limit it.

[0061] Although the present invention has been described in detail with reference to the above-mentioned specific technical solutions, those skilled in the art should understand that they can still modify the above-mentioned specific technical solutions, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the present invention.

Claims

1. A polypropylene insulated buried cable for an airport navigation lighting system, characterized in that: The buried cable is composed of a conductor (1) and a conductor shielding layer (2), an insulating layer (3), an insulating shielding layer (4), a metal shielding layer (5), a water-blocking layer (6) and a sheath layer (7) which are arranged in sequence from the inside to the outside outside the conductor (1); The conductor shielding layer (2), the insulating layer (3), and the insulating shielding layer (4) are respectively made of polypropylene material, and the conductor shielding layer (2), the insulating layer (3), and the insulating shielding layer (4) are horizontal three-layer co-extruded structures; The water-blocking layer (6) is at least one layer of overlapping wrapped structure of a non-conductive water-blocking tape.

2. The polypropylene insulated buried cable for airport navigation lighting system according to claim 1, characterized in that: The conductor shielding layer (2) is a polypropylene shielding material structure, and the extruded thickness of the conductor shielding layer (2) is 0.50-0.60 mm.

3. The polypropylene insulated buried cable for airport navigation lighting system according to claim 1, characterized in that: The insulating layer (3) is a polypropylene insulating structure, and the extruded thickness of the insulating layer (3) is 2.8-3.2 mm.

4. The polypropylene insulated buried cable for airport navigation lighting system according to claim 1, characterized in that: The insulating shielding layer (4) is a polypropylene shielding material structure, and the extruded thickness of the insulating shielding layer (4) is 0.56-0.60 mm.

5. The polypropylene insulated buried cable for airport navigation lighting system according to claim 1, characterized in that: The conductor (1) is a twisted structure of multiple copper strands, and the twisted gaps of the copper strands are filled with water-blocking yarn or water-blocking powder; Each copper strand is formed by twisting together a number of copper wires with a single wire diameter of 1.04 to 1.06 mm.

6. The polypropylene insulated buried cable for airport navigation lighting system according to claim 5, characterized in that: The copper strands of the conductor (1) have a pitch diameter ratio of 18 to 22 times; The diameter of the conductor (1) ranges from 3.1 to 3.2 mm.

7. The polypropylene insulated buried cable for airport navigation lighting system according to claim 1, characterized in that: The metal shielding layer (5) is a single-layer overlapping wrapped structure of copper tape, and the overlapping wrapping ratio is ≥15%.

8. The polypropylene insulated buried cable for airport navigation lighting system according to claim 1, characterized in that: The thickness of the non-conductive water-blocking tape of the water-blocking layer (6) is 0.25 to 0.35 mm; The overlapping wrapping rate of the non-conductive water-blocking tape of the water-blocking layer (6) is 25 to 50%.

9. The polypropylene insulated buried cable for airport navigation lighting system according to claim 1, characterized in that: The sheath layer (7) is a rodent-proof and ant-proof sheath material structure.

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