Flexible lead sheath low-voltage armored cable

Abstract

The utility model discloses a flexible lead sheath low-voltage armored cable, which comprises an inner conductor, a Kevlar woven mesh, a double-layer polyethylene longitudinally-wrapped water-blocking inner isolating layer, a PVC (polyvinyl chloride) insulating layer, a double-layer polyethylene longitudinally-wrapped water-blocking outer isolating layer, an extruded lead sheath layer, a PVC liner layer, an aluminum wire armored layer and a PVC outer sheath, a plurality of tinned copper wire stranded conductor layers are arranged outside the galvanized steel monofilament inner core, the diameter of the inner conductor is 7mm-30mm, the thickness of the extruded lead sheath layer is 1mm-2mm, and the outer diameter of the PVC outer sheath is 25mm-60mm. The cable has better flexibility and bending resistance, is helpful for reducing the deformation and breakage of the conductor copper wires and preventing the lead sheath from cracking, has excellent waterproof and water-blocking performance, and prolongs the service life.

Description

Technical Field

[0001] The utility model relates to the technical field of cables, in particular to a soft lead sheathed low-voltage armored cable. Background Art

[0002] Lead sheathed cables used in low-voltage power distribution systems can be installed indoors or outdoors, laid in cable ducts or directly buried. Lead sheaths can prevent corrosion from aromatic hydrocarbon compounds, improve power supply reliability, and have high application value. Ordinary lead sheathed cables have average flexibility and insufficient tensile strength. During the laying and installation process, the cables are subjected to different degrees of bending, and the conductors are subjected to torsional stress, which can easily cause copper wire deformation and breakage, affecting electrical properties. In addition, due to the complex factors of climate and underground laying environment, water vapor can easily penetrate into the cables, causing water tree aging, and damage to cable insulation, which becomes a potential hidden danger affecting the safe operation of the cables. Utility Model Content

[0003] The utility model aims to solve the technical problem of providing a soft lead sheathed low-voltage armored cable with better flexibility and bending resistance, which helps to reduce the deformation and breakage of the conductor copper wire and prevent the lead sheath from cracking, has excellent waterproof and water-blocking properties, and prolongs the service life.

[0004] The utility model solves the above technical problems through the following technical solutions.

[0005] A soft lead sheathed low-voltage armored cable, comprising an inner conductor and a Kevlar braided mesh, a double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer, a PVC insulation layer, a double-layer polyethylene longitudinally wrapped water-blocking outer isolation layer, an extruded lead sheath layer, a PVC cushion layer, an aluminum wire armor layer and a PVC outer sheath, which are sequentially coated on the outside of the inner conductor. The inner conductor comprises a galvanized steel monofilament inner core, and a multi-layer tinned copper wire stranded conductor layer is arranged on the outside of the galvanized steel monofilament inner core. The inner conductor has a diameter of 7mm to 30mm, the extruded lead sheath layer has a thickness of 1mm to 2mm, and the outer diameter of the PVC outer sheath is 25mm to 60mm.

[0006] Preferably, the Kevlar braided mesh is formed by a plurality of Kevlar threads being mutually spirally wound in opposite directions and the braiding density is not less than 95%.

[0007] Preferably, the double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer and the double-layer polyethylene longitudinally wrapped water-blocking outer isolation layer are both double-layer polyethylene water-blocking tape longitudinally overlapped and wrapped structures with an overlap rate of 40% to 60%, and the double-layer polyethylene water-blocking tape is formed by co-extrusion of an MDPE water-blocking inner layer and an LDPE water-blocking outer layer.

[0008] Preferably, the PVC insulation layer has a thickness of 0.9 mm to 2.4 mm.

[0009] Preferably, the thickness of the extruded lead sheath layer is 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm or 1.8 mm.

[0010] Preferably, the thickness of the PVC outer sheath is 1.8 mm, 1.9 mm, 2 mm, 2.1 mm, 2.3 mm, 2.4 mm or 2.6 mm.

[0011] Preferably, the thickness of the aluminum wire armor layer is 1.3 mm, 1.6 mm, 2 mm or 2.5 mm.

[0012] Preferably, the aluminum wire armor layer includes an inner and outer double layer of aluminum alloy wire plain woven mesh, the inner layer of aluminum alloy wire plain woven mesh is a plain woven mesh structure woven from fine aluminum alloy wires, and the outer layer of aluminum alloy wire plain woven mesh is a plain woven mesh structure woven from coarse aluminum alloy wires, the diameter of the coarse aluminum alloy wires is 2 to 5 times the diameter of the fine aluminum alloy wires, and the weaving density of the inner layer of aluminum alloy wire plain woven mesh is greater than the weaving density of the outer layer of aluminum alloy wire plain woven mesh.

[0013] Preferably, the aluminum wire armor layer is coated with insulating lubricating grease.

[0014] Preferably, the inner core diameter of the galvanized steel monofilament is 2 mm to 3 mm, and the diameter of the tinned copper wire is 1.6 mm to 3 mm.

[0015] Beneficial effects of the utility model:

[0016] 1. By optimizing the inner conductor structure of galvanized steel monofilament inner core and multi-layer tinned copper wire stranded conductor layer, the flexibility and bending resistance of the inner conductor are improved. When the cable is subjected to laying and bending, the linear expansion coefficient of the galvanized steel monofilament is smaller than that of the tinned copper wire, which helps to balance the absorption of the cable extension and suppress the extension force at the cable end. The tensile strength of the galvanized steel wire is greater than that of the tinned copper wire, which suppresses the occurrence of wire breakage. By adding Kevlar braided mesh, it helps to prevent the double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer from penetrating into the tinned copper wires of the tinned copper wire stranded conductor layer and causing adhesion, which is beneficial to enhance the flexibility and bending resistance of the inner conductor. At the same time, it effectively protects the water-blocking inner isolation layer, improves the durability and applicability, and enhances the adaptability of laying in pipelines and complex underground environments.

[0017] 2. By adding a double-layer polyethylene longitudinal water-blocking inner and outer isolation layer on the inside and outside of the insulation layer to prevent water vapor from penetrating, the water tree aging phenomenon of the insulation layer is delayed and the service life is extended. The longitudinal overlap wrapping structure of the double-layer polyethylene water-blocking tape helps to enhance the waterproof and water-blocking properties and has better anti-bending performance.

[0018] 3. The inner and outer sides of the extruded lead sheath layer are double-layer polyethylene longitudinal water-blocking outer isolation layer and PVC cushion layer, which protect the extruded lead sheath layer, improve the bending resistance, and prevent the extruded lead sheath layer from cracking. By adding a PVC cushion layer between the extruded lead sheath layer and the aluminum wire armor layer, the flexibility is improved while avoiding friction damage to the extruded lead sheath layer, thereby enhancing the adaptability of pipelines and laying in complex underground environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the cross-sectional structure of an embodiment of the utility model.

[0020] In the figure: 1-inner conductor, 2-Kevlar braided mesh, 3-double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer, 4-PVC insulation layer, 5-double-layer polyethylene longitudinally wrapped water-blocking outer isolation layer, 6-extruded lead sheath layer, 7-PVC cushion layer, 8-aluminum wire armor layer, 9-PVC outer sheath, 10-galvanized steel monofilament inner core, 11-tinned copper wire stranded conductor layer. DETAILED DESCRIPTION

[0021] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0022] like Figure 1 As shown, the soft lead sheathed low-voltage armored cable of the embodiment of the utility model comprises an inner conductor 1, the inner conductor 1 has a diameter of 7 mm to 30 mm, the inner conductor 1 comprises a galvanized steel monofilament inner core 10, further, the galvanized steel monofilament inner core 10 has a diameter of 2 mm to 3 mm, and the galvanized steel monofilament inner core 10 is provided with a multi-layer tinned copper wire twisted conductor layer 11 on the outside, which is three layers in this embodiment, and further, the diameter of the tinned copper wire is 1.6 mm to 3 mm.

[0023] The inner conductor 1 is coated with a Kevlar braided mesh 2, a double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer 3, a PVC insulation layer 4, a double-layer polyethylene longitudinally wrapped water-blocking outer isolation layer 5, an extruded lead sheath layer 6, a PVC cushion layer 7, an aluminum wire armor layer 8 and a PVC outer sheath 9 in sequence. Furthermore, the double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer 3 and the double-layer polyethylene longitudinally wrapped water-blocking outer isolation layer 5 are both double-layer polyethylene water-blocking tape longitudinally overlapped and wrapped structures with an overlap rate of 40% to 60%. The double-layer polyethylene water-blocking tape is formed by co-extrusion of an MDPE water-blocking inner layer and an LDPE water-blocking outer layer. In one embodiment, the Kevlar braided mesh 2 is composed of a plurality of Kevlar wires that are mutually reversely spirally wound and woven, and the braiding density is not less than 95%. The thickness of the PVC insulation layer 4 is 0.9mm to 2.4mm. The thickness of the extruded lead sheath layer 6 is 1mm to 2mm, and further, the thickness of the extruded lead sheath layer 6 is 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm or 1.8mm. In one embodiment, the aluminum wire armor layer 8 includes an inner and outer double-layer aluminum alloy wire flat woven mesh, the inner layer aluminum alloy wire flat woven mesh is a flat woven mesh structure woven from fine aluminum alloy wires, and the outer layer aluminum alloy wire flat woven mesh is a flat woven mesh structure woven from coarse aluminum alloy wires, the diameter of the coarse aluminum alloy wire is 2 to 5 times the diameter of the fine aluminum alloy wire, and the weaving density of the inner layer aluminum alloy wire flat woven mesh is greater than the weaving density of the outer layer aluminum alloy wire flat woven mesh. The aluminum wire armor layer 8 is coated with insulating lubricating grease. The thickness of the aluminum wire armor layer 8 is 1.3mm, 1.6mm, 2mm or 2.5mm. The thickness of the PVC outer sheath 9 is 1.8 mm, 1.9 mm, 2 mm, 2.1 mm, 2.3 mm, 2.4 mm or 2.6 mm. The outer diameter of the PVC outer sheath 9 is 25 mm to 60 mm.

[0024] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. Soft lead sheathed low voltage armored cable, characterized by: The invention comprises an inner conductor (1) and a Kevlar braided mesh (2), a double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer (3), a PVC insulation layer (4), a double-layer polyethylene longitudinally wrapped water-blocking outer isolation layer (5), an extruded lead sheath layer (6), a PVC cushion layer (7), an aluminum wire armor layer (8) and a PVC outer sheath (9) which are sequentially coated on the outside of the inner conductor (1), wherein the inner conductor (1) comprises a galvanized steel monofilament inner core (10), and a multi-layer tinned copper wire stranded conductor layer (11) is arranged on the outside of the galvanized steel monofilament inner core (10), the inner conductor (1) has a diameter of 7 mm to 30 mm, the extruded lead sheath layer (6) has a thickness of 1 mm to 2 mm, and the outer diameter of the PVC outer sheath (9) is 25 mm to 60 mm.

2. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized in that: The Kevlar braided net (2) is formed by a plurality of Kevlar threads being mutually spirally wound and braided in opposite directions, and the braiding density is not less than 95%.

3. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized in that: The double-layer polyethylene longitudinally wrapped water-blocking inner isolation layer (3) and the double-layer polyethylene longitudinally wrapped water-blocking outer isolation layer (5) are both double-layer polyethylene water-blocking tape longitudinally overlapped and wrapped structures with an overlap rate of 40% to 60%. The double-layer polyethylene water-blocking tape is formed by co-extrusion of an MDPE water-blocking inner layer and an LDPE water-blocking outer layer.

4. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized in that: The thickness of the PVC insulation layer (4) is 0.9 mm to 2.4 mm.

5. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized in that: The thickness of the extruded lead sheath layer (6) is 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm or 1.8 mm.

6. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized by: The thickness of the PVC outer sheath (9) is 1.8 mm, 1.9 mm, 2 mm, 2.1 mm, 2.3 mm, 2.4 mm or 2.6 mm.

7. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized by: The thickness of the aluminum wire armor layer (8) is 1.3 mm, 1.6 mm, 2 mm or 2.5 mm.

8. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized by: The aluminum wire armor layer (8) comprises an inner and outer double-layer aluminum alloy wire flat woven mesh, wherein the inner layer aluminum alloy wire flat woven mesh is a flat woven mesh structure formed by weaving fine aluminum alloy wires, and the outer layer aluminum alloy wire flat woven mesh is a flat woven mesh structure formed by weaving coarse aluminum alloy wires, wherein the diameter of the coarse aluminum alloy wires is 2 to 5 times the diameter of the fine aluminum alloy wires, and the weaving density of the inner layer aluminum alloy wire flat woven mesh is greater than the weaving density of the outer layer aluminum alloy wire flat woven mesh.

9. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized by: The aluminum wire armor layer (8) is coated with insulating lubricating grease.

10. The flexible lead sheathed low-voltage armored cable according to claim 1 is characterized by: The diameter of the galvanized steel monofilament inner core (10) is 2 mm to 3 mm, and the diameter of the tinned copper wire is 1.6 mm to 3 mm.

Images