Anti-cracking cold-resistant cable
By using a multi-layer composite structure design and a copper conductor stranded structure, the problem of cable cracking caused by poor stress dispersion in extreme cold environments was solved, achieving stability and flexibility of the cable at low temperatures and enhancing the cable's durability and wear resistance.
Patent Information
- Application Number
- CN202421995931.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-18
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-08-18
AI Technical Summary
In the prior art, the existing technology has failed to effectively solve the problem of cable cracking caused by poor material stress dispersion in extremely cold environments, especially under the stress of cable installation and contact parts, which makes the cable prone to damage at low temperatures.
The cable adopts a multi-layer composite structure design, including a conductor core, an inner shielding layer, an inner insulation layer, an outer insulation layer, an aramid braided layer, and an outer sheath. The inner insulation layer and the outer sheath adopt a sandwich structure of silicone rubber and cross-linked polyethylene. The middle layer has raised ribs, which disperse stress and, combined with the copper conductor stranded structure, reduce stress concentration, thereby enhancing the cable's flexibility and durability.
It effectively disperses external mechanical stress, reduces the risk of cable cracking at low temperatures, improves the stability and flexibility of the cable in extreme environments, reduces wear risk, and ensures the long-term safety and reliability of the cable in low-temperature environments.
Smart Images
Figure CN223501593U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of wire and cable technology, and more specifically to crack-resistant and cold-resistant cables. Background Technology
[0002] Cold-resistant cables, especially special cables used in low-temperature environments, are required to maintain basic electrical and mechanical properties in low-temperature and cold environments, while also maintaining cable flexibility and resisting brittleness and cracking. They are particularly suitable for applications in extremely cold environments, such as northern frigid regions, cold storage facilities, marine engineering, and polar scientific experiments and exploration, to maintain the long-term safety and reliability of the cables.
[0003] In existing technologies, the design of low-temperature resistant cables typically employs materials with low-temperature toughness to manufacture the insulation layer and outer sheath. Examples include ethylene-vinyl acetate copolymer (EVA), polyvinyl chloride (PVC), cross-linked polyethylene (XLPE), and chlorinated polyethylene (CPE), which maintain their elasticity at low temperatures and are less prone to embrittlement or cracking. Furthermore, attempts have been made to improve sheath performance by adding plasticizers and anti-cracking modifiers to enhance its toughness and flexibility. Currently, in low-temperature resistant cable designs, a single-layer sheath design is often used. Although these materials, such as special cold-resistant PVC and chlorinated polyethylene, possess excellent elasticity and cold resistance, the different thickness distributions and expansion coefficients of the various structural layers in extreme environments lead to poor stress dispersion during continuous low-temperature and cold-weather applications. This results in material cracking due to mechanical stress concentration. In addition, due to the stress on the cable during installation and at the contact points such as sheaths and conduits, the outer sheath cracks. Combined with the brittle cracking and fatigue cracking caused by long-term cold environments, the cable is extremely prone to breakage and damage, affecting its stability and safety in low-temperature environments. Utility Model Content
[0004] To address the technical problems existing in existing crack-resistant and cold-resistant cables, the first aspect of this utility model proposes a crack-resistant and cold-resistant cable, comprising:
[0005] The conductor core consists of multiple stranded copper conductors;
[0006] The inner shielding layer is extruded onto the outer wall of the conductor core;
[0007] An inner insulating layer is extruded onto the outer wall of the inner shielding layer;
[0008] The outer insulation layer is extruded onto the outer wall of the inner insulation layer;
[0009] An aramid braided layer covers the outer wall of the outer insulation layer;
[0010] The outer protective layer is extruded onto the outer wall of the aramid braided layer;
[0011] The inner insulation layer includes a silicone rubber insulation layer, and the outer insulation layer includes a cross-linked polyethylene insulation layer.
[0012] The outer sheath comprises a sandwich-type three-layer structure consisting of a double-layer polyvinyl chloride insulation layer and a single-layer silicone rubber insulation layer. The inner and outer layers are both polyvinyl chloride insulation layers, and the middle layer is a silicone rubber insulation layer. The inner and outer surfaces of the middle layer are respectively provided with a first rib and a second rib. The first rib and the second rib are parallel to each other and both extend along the axial direction of the cable.
[0013] Multiple first and second reinforcing bars are periodically arranged in the circumferential direction of the cable, and each set of first and second reinforcing bars is staggered from each other.
[0014] Alternatively, the first and second reinforcing bars can be arranged in the circumferential direction of the cable at intervals of 30°, 45°, and 60°.
[0015] Alternatively, the first and second ribs may have the same shape, and be formed into one of the following: a semi-circular shape, a semi-elliptical shape, a triangle shape, or a convex shape.
[0016] Alternatively, the height of the first and second reinforcing bars can be between 0.5 and 1 mm.
[0017] Alternatively, the conductor core may comprise three to five layers of concentrically stranded conductors, each layer being stranded in the same direction, wherein at least two adjacent layers have the same strand pitch.
[0018] Alternatively, the conductor core comprises four layers of concentric stranded conductors, wherein the pitch ratio of the second stranded conductor is 18 to 20, the pitch of the third stranded conductor is the same as that of the second stranded conductor, and the pitch ratio of the fourth stranded conductor is 16 to 18.
[0019] Alternatively, the thickness of the inner insulating layer may be less than the thickness of the outer insulating layer.
[0020] Alternatively, the thickness ratio of the inner insulating layer to the outer insulating layer is 3:7 to 4:6.
[0021] Alternatively, the thickness of the inner layer is H1, the thickness of the outer layer is H2, and the thickness of the intermediate layer is H3, wherein H2>H1>H3.
[0022] Alternatively, the thickness H2 of the outer layer is three times the thickness H3 of the intermediate layer, and the thickness H1 of the inner layer is twice the thickness H3 of the intermediate layer.
[0023] The conductor of the anti-crack and cold-resistant cable in the above embodiments of the present invention adopts a copper conductor stranded structure. The gap between the stranded conductors can be compressed during expansion and contraction. Combined with the composite insulation layer formed by silicone rubber and cross-linked polyethylene, it can reduce the mutual stress between the conductor and the insulation layer at low temperatures. At the same time, the outer sheath adopts a three-layer composite structure of polyvinyl chloride and silicone rubber, with silicone rubber in the middle layer, which can maintain better elasticity at low temperatures, thereby reducing the stress on the polyvinyl chloride structural layer and delaying fatigue cracking.
[0024] Compared with existing technologies, the crack-resistant and cold-resistant cable proposed in this invention significantly enhances the cable's mechanical protection capabilities through a combination of double-layer PVC and single-layer silicone rubber. The PVC layer provides excellent abrasion resistance and chemical corrosion resistance, while the silicone rubber layer increases the cable's cold resistance and elasticity, preventing embrittlement at low temperatures. On one hand, the inner and outer layers of the double PVC effectively disperse external mechanical stress; on the other hand, the intermediate silicone rubber layer further reduces the risk of material cracking by absorbing stress. This composite structure design ensures the cable's stability and durability in low-temperature environments.
[0025] Meanwhile, the raised ribs on both sides of the silicone rubber insulation layer in the middle layer effectively increase the surface area of the cable's outer sheath, thereby dispersing external pressure, reducing the problem of excessive stress at a single point, and preventing the cable from cracking due to external compression or impact at low temperatures. Furthermore, the periodic arrangement of the ribs in the circumferential direction of the cable increases structural strength while reducing friction between the cable and other surfaces during installation and use, thus lowering the risk of wear on the outer sheath. The staggered design of the ribs allows for a more even distribution of stress during bending and torsion, reducing localized stress concentration and further improving the cable's flexibility and fatigue resistance. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the structure of the crack-resistant and cold-resistant cable shown in this utility model.
[0027] Figure 2 This is a schematic diagram of the structure of the outer protective layer shown in this utility model. Detailed Implementation
[0028] To better understand the technical content of this utility model, specific embodiments are provided below in conjunction with the accompanying drawings.
[0029] Combination Figure 1 As shown, the crack-resistant and cold-resistant cable proposed in the first aspect of this utility model mainly includes a conductor core 1, an inner shielding layer 2, an inner insulation layer 3, an outer insulation layer 4, an aramid braided layer 5, and an outer sheath 6 from the inside out. The conductor core 1 adopts a stranded structure of multiple fine copper wires, which can improve the flexibility of the conductor and reduce expansion and contraction stress.
[0030] In an optional embodiment, the conductor core 1 includes three to five layers of concentric stranded conductors, each layer of conductors being stranded in the same direction, wherein at least two adjacent layers of conductors have the same strand pitch.
[0031] Specifically, conductor core 1 includes four layers of concentric stranded conductors. The pitch ratio of the second stranded conductor is 18 to 20, the pitch of the third stranded conductor is the same as that of the second stranded conductor, and the pitch ratio of the fourth stranded conductor is 16 to 18.
[0032] Thus, in multilayer stranded conductors, at least two adjacent conductors are in line contact. Since there are gaps between each conductor layer, the conductor expands and contracts when the temperature changes. Therefore, the conductor between the inner and outer layers in line contact can penetrate into the gaps between the layers to reduce the stress on the insulation layer caused by the expansion and contraction of the conductor.
[0033] Furthermore, the inner shielding layer 2 is extruded onto the outer wall of the conductor core 1, the inner insulation layer 3 is extruded onto the outer wall of the inner shielding layer 2, the outer insulation layer 4 is extruded onto the outer wall of the inner insulation layer 3, the aramid braided layer 5 is covered onto the outer wall of the outer insulation layer 4, and the outer sheath 6 is extruded onto the outer wall of the aramid braided layer 5.
[0034] The inner shielding layer 2 can be selected as a semi-conductive wrapping tape with a wrapping overlap rate of more than 70%, which makes the conductor core compact and fixed into a circular cross-section.
[0035] Thus, dividing the insulation layer into an inner insulation layer 3 and an outer insulation layer 4 reduces the thickness of each insulation layer. The inner insulation layer 3 comprises a silicone rubber insulation layer, and the outer insulation layer 4 comprises a cross-linked polyethylene insulation layer. The silicone rubber insulation layer has good weather resistance, especially maintaining good elasticity at extremely low temperatures. Therefore, it forms a buffer layer between the outer insulation layer 4 and the conductor, reducing the stress on the thinned polyethylene insulation layer during temperature changes.
[0036] In an optional embodiment, the thickness of the inner insulating layer 3 is less than the thickness of the outer insulating layer 4.
[0037] Alternatively, the thickness ratio of the inner insulating layer 3 to the outer insulating layer 4 can be 3:7 to 4:6. The inner and outer insulating layers are tightly connected, which ensures sufficient heat capacity, reduces the rate of expansion and contraction, and also reduces the stress on the outer insulating layer 4 through deformation of the inner insulating layer.
[0038] Furthermore, the braiding density of the aramid fiber braided layer 5 is greater than 80%, and the braiding angle is 45%. The aramid fiber braided layer 5 can provide better tensile strength for the cable, thereby reducing the axial stress of the cable.
[0039] In a further embodiment, the outer sheath 6 includes a three-layer structure, particularly a sandwich structure consisting of a double-layer polyvinyl chloride insulation layer and a single-layer silicone rubber insulation layer. The inner layer 61 and the outer layer 63 are both polyvinyl chloride insulation layers, and the middle layer 62 is a silicone rubber insulation layer. Furthermore, the inner and outer surfaces of the middle layer 62 are respectively provided with a first rib 621 and a second rib 622, the first rib 621 and the second rib 622 being parallel to each other and both extending along the axial direction of the cable.
[0040] In an embodiment of this utility model, a plurality of first ribs 621 and second ribs 622 are periodically arranged in the circumferential direction of the cable, and each set of first ribs 621 and second ribs 622 is staggered from each other.
[0041] In particular, the first rib 621 and the second rib 622 are arranged in the circumferential direction of the cable at intervals of 30°, 45°, and 60°, and are staggered from each other.
[0042] As an optional embodiment, the first rib 621 and the second rib 622 have the same shape and are formed into one of the following: a slightly semi-circular shape, a slightly semi-elliptical shape, a triangle shape, or a convex shape. They can be integrally formed based on a three-layer co-extrusion process (with the die head corresponding to the shape design).
[0043] The height of the first rib 621 and the second rib 622 is between 0.5 and 1 mm, and they adopt the same design.
[0044] This configuration creates a hard-soft-hard sandwich structure for the outer protective layer. The middle layer 62 compensates for the expansion and contraction of the inner and outer layers under hot and cold conditions, thereby reducing the stress on the inner layer 61 and the outer layer 63.
[0045] In the above embodiments, before extruding the outer insulation layer 4, an adhesive is coated on the surface of the inner insulation layer 3 to improve the interlayer bonding force between the inner insulation layer 3 and the outer insulation layer 4. The adhesive is also coated on the outer surface of the inner layer 61 and the outer surface of the intermediate layer 62 to make the integrity of the inner layer 61, the intermediate layer 62 and the outer layer 63 stronger, and the intermediate layer 62 more effective in absorbing stress. Therefore, by adding a silicone rubber layer in the insulation layer and the outer sheath, the deformation capability of the structural layer can be improved, especially at low temperatures, so as to reduce the stress on the structural layer at low temperatures.
[0046] Optionally, the thickness of the inner layer 61 is H1, the thickness of the outer layer 63 is H2, and the thickness of the middle layer 62 is H3, wherein H2>H1>H3.
[0047] Alternatively, the thickness H2 of the outer layer 63 is three times the thickness H3 of the intermediate layer 62, and the thickness H1 of the inner layer 61 is twice the thickness H3 of the intermediate layer 62.
[0048] In an optional embodiment, the inner and outer layers of the intermediate layer 62 are provided with raised ribs 621, which extend along the axial direction of the cable. The cross-sectional shape of the ribs 621 is arc-shaped, and they are formed by extrusion through a die.
[0049] Thus, by setting the ribs 621, the tightness of the connection between the intermediate layer 62 and the inner layer 61 and the outer layer 63 can be further increased, making the overall integrity of the outer insulation layer stronger.
[0050] In conjunction with the above embodiments, the conductor of this utility model adopts a copper conductor stranded structure. The gap between the stranded conductors can be compressed during expansion and contraction. Combined with the composite insulation layer formed by silicone rubber and cross-linked polyethylene, it can reduce the mutual stress between the conductor and the insulation layer at low temperatures. The outer sheath adopts a three-layer composite structure of polyvinyl chloride and silicone rubber, with silicone rubber in the middle layer, which can maintain better elasticity at low temperatures, thereby reducing the stress on the polyvinyl chloride structural layer and delaying fatigue cracking.
[0051] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this invention shall be determined by the claims.
Claims
1. A crack-resistant and cold-resistant cable, characterized in that, include: Conductor core (1), comprising multiple stranded copper conductors; The inner shielding layer (2) is extruded onto the outer wall of the conductor core (1); The inner insulating layer (3) is extruded onto the outer wall of the inner shielding layer (2); The outer insulating layer (4) is extruded onto the outer wall of the inner insulating layer (3); An aramid braided layer (5) covers the outer wall of the outer insulation layer (4); The outer protective layer (6) is extruded onto the outer wall of the aramid braided layer (5); The inner insulation layer (3) includes a silicone rubber insulation layer, and the outer insulation layer (4) includes a cross-linked polyethylene insulation layer. The outer sheath (6) is a sandwich structure consisting of a double layer of polyvinyl chloride insulation and a single layer of silicone rubber insulation. The inner layer (61) and the outer layer (63) are both polyvinyl chloride insulation layers, and the middle layer (62) is a silicone rubber insulation layer. Furthermore, the inner and outer surfaces of the middle layer (62) are respectively provided with a first rib (621) and a second rib (622). The first rib (621) and the second rib (622) are parallel to each other and both extend along the axial direction of the cable. Multiple first ribs (621) and second ribs (622) are periodically arranged in the circumferential direction of the cable, and each set of first ribs (621) and second ribs (622) is staggered from each other.
2. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The first rib (621) and the second rib (622) are arranged in the circumferential direction of the cable at intervals of 30°, 45° and 60°.
3. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The first rib (621) and the second rib (622) have the same shape and are formed into one of the following: a semi-circular shape, a semi-elliptical shape, a triangle shape, or a convex shape.
4. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The height of the first rib (621) and the second rib (622) is between 0.5 and 1 mm.
5. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The conductor core (1) comprises three to five layers of concentric stranded conductors, each layer of conductors being stranded in the same direction, wherein at least two adjacent layers of conductors have the same stranding pitch.
6. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The conductor core (1) comprises four layers of concentric stranded conductors. The pitch ratio of the second stranded conductor is 18 to 20, the pitch of the third stranded conductor is the same as that of the second stranded conductor, and the pitch ratio of the fourth stranded conductor is 16 to 18.
7. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The thickness of the inner insulating layer (3) is less than the thickness of the outer insulating layer (4).
8. The crack-resistant and cold-resistant cable according to claim 4, characterized in that, The thickness ratio of the inner insulation layer (3) to the outer insulation layer (4) is 3:7 to 4:
6.
9. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The thickness of the inner layer (61) is H1, the thickness of the outer layer (63) is H2, and the thickness of the intermediate layer (62) is H3, wherein H2>H1>H3.
10. The crack-resistant and cold-resistant cable according to claim 1, characterized in that, The thickness H2 of the outer layer (63) is three times the thickness H3 of the intermediate layer (62), and the thickness H1 of the inner layer (61) is twice the thickness H3 of the intermediate layer (62).