CN211788232U

CN211788232U - Temperature-resistant and shrinkage-cracking-resistant cable

Info

Publication number: CN211788232U
Application number: CN202020527731.2U
Authority: CN
Inventors: 王福志; 黄伟立; 林荣茜; 朱金龙
Original assignee: Zhejiang Wanma Co Ltd
Current assignee: Zhejiang Wanma Co Ltd
Priority date: 2020-04-10
Filing date: 2020-04-10
Publication date: 2020-10-27
Anticipated expiration: 2030-04-10

Abstract

The utility model relates to a high pressure, superhigh pressure cable technical field, the cable temperature resistant variation ability to present high pressure, superhigh pressure is poor, the problem of fracture and shrink destruction appear easily under great difference in temperature, provides a shrink fracture is prevented to temperature resistant cable, metal covering including conductor body and cladding conductor body, the conductor body includes insulating layer, the insulating barrier layer of cladding insulating layer, the band layer of cladding insulating barrier layer and the flexible buffer layer of setting between metal covering and band layer of the insulating barrier layer of insulating barrier layer, cladding conductor barrier layer of heart yearn, cladding heart yearn, the surface of flexible buffer layer and inside are equipped with the micropore of a plurality of dispersions. The utility model discloses a cable sets up the metal covering that has the line of cladding on conductor body and plays better guard action, sets up flexible buffer layer simultaneously between metal covering and conductor body and plays deformation stress cushioning effect, can alleviate high pressure, the phenomenon that fracture and shrink destruction appear easily under great difference in temperature in the superhigh voltage cable.

Description

Temperature-resistant and shrinkage-cracking-resistant cable

Technical Field

The utility model relates to a high pressure, superhigh pressure cable technical field, concretely relates to shrink cable that ftractures is prevented to temperature resistant.

Background

At present, the high-voltage and ultrahigh-voltage power cables are almost all insulated power cables by adopting crosslinked polyethylene. The insulating layer of the crosslinked polyethylene insulated cable is crosslinked polyethylene, and has good electrical property and stable heat-resistant and aging-resistant properties. However, the crosslinked polyethylene insulated cable has poor high and low temperature cross-linking resistance, and is easy to crack and shrink and damage under a large temperature difference, and meanwhile, the crosslinked polyethylene is a thermosetting material, and needs to provide enough heat energy to perform polyethylene cross-linking in the production process, so that the production cost is relatively high. Meanwhile, the crosslinked polyethylene is a thermosetting material, cannot be recycled and is not beneficial to environmental protection.

Chinese patent CN 201820188584.3, the patent name "a crosslinked polyethylene insulated power cable" discloses a crosslinked polyethylene insulated power cable including wire bundle and protective layer, the wire bundle comprises wire and first insulating layer, first insulating layer parcel is in the wire outside, the wire is formed by the transposition of many copper lines, the protective layer parcel is in the wire bundle outside, the protective layer is by interior filling layer, tie the layer, the inner sheath, the second insulating layer, the oversheath of being in proper order outward, first insulating layer and second insulating layer are prepared by crosslinked polyethylene material and are formed. The cable of this patent still has the drawbacks of the current crosslinked polyethylene insulated cables.

SUMMERY OF THE UTILITY MODEL

The cable temperature variation resistance to present high pressure, superhigh pressure is poor, the problem of fracture and shrink destruction appears easily under great difference in temperature, the utility model provides a shrink fracture is prevented to temperature resistant cable alleviates high pressure, superhigh pressure cable and appears the fracture easily under great difference in temperature and shrink destruction's phenomenon.

The utility model provides a following technical scheme:

the utility model provides a temperature resistant shrink crack's cable of preventing, includes conductor body and the metal covering of cladding conductor body, conductor body includes heart yearn, the conductor shielding layer of cladding heart yearn, the insulating layer of cladding conductor shielding layer, the insulating barrier of cladding insulating layer, the band layer of cladding insulating barrier and the flexible buffer layer of setting between metal covering and band layer.

The utility model discloses a cable that shrink fracture is prevented to temperature resistant sets up the metal outside the conductor and plays the guard action to set up flexible buffer layer between the red metal covering of conductor body, flexible buffer layer can be extruded or expand and play good deformation cushioning effect when the cable difference in temperature is great to appear inflation or shrink deformation, avoids the rigid contact between conductor body and the metal covering.

As the improvement of the utility model, the surface and the inside of the flexible buffer layer are provided with a plurality of dispersed micropores. The micropores play two roles, namely, the deformation space of the flexible buffer layer is increased, and the air filled in the micropores is favorable for playing a certain heat insulation role.

As an improvement of the utility model, the flexible buffer layer is a polytetrafluoroethylene buffer layer. The polytetrafluoroethylene buffer layer is obtained by coating a polytetrafluoroethylene thick film with the thickness of 200-300 mu m, and the polytetrafluoroethylene has the characteristics of good temperature resistance, impact resistance and the like. The micropores arranged on the polytetrafluoroethylene buffer layer can be formed by adding certain calcium acetate into the raw material of the polytetrafluoroethylene thick film and utilizing the thermal decomposition of the calcium acetate.

As the utility model discloses an improvement, the metal covering comprises the protruding circle in big footpath and the concave circle in path that a plurality of coaxial lines were arranged, the line that becomes consecutive undulation on the length direction of conductor body is enclosed to the protruding circle in big footpath and the concave circle in path, the medial surface of the concave circle in path closely pastes and leans on the conductor body. The deformability of the metal sleeve can be enhanced by forming the undulating lines, eliminating or reducing the deformation stress.

As the utility model discloses an improvement, the convex circle of big footpath and the concave circle of little warp on conductor body length direction's cross-section are circular-arcly, and the radius that the circular-arc cross-section of the convex circle of big footpath corresponds is less than the radius that the concave circle of path corresponds, the central angle that the circular-arc cross-section of the convex circle of big footpath corresponds the central angle that the concave circle of path corresponds. Because the conductor body is hugged closely to the medial surface of path concave ring, the stress that produces in path concave ring department under the big difference in temperature is bigger some, with being not less than big path concave ring of the central angle setting of path concave ring, and the radius that the path concave ring corresponds bigger, the bottom both sides of path concave ring are gentler, can absorb more stress.

As the improvement of the utility model, the insulating layer is a modified polypropylene insulating layer. The modified polypropylene has better electrical property, ageing resistance and mechanical physical property.

As an improvement of the utility model, the conductor shielding layer, the insulating layer and the insulating shielding layer are prepared through a three-layer co-extrusion mode.

As an improvement of the utility model, the cable further comprises a low temperature resistant protective sleeve which is closely coated on the surface of the metal sleeve after being vacuumized. The low-temperature-resistant protective sleeve is tightly attached to the surface of the metal sleeve after being processed by a vacuumizing process, so that a better low-temperature-resistant anti-shrinkage deformation effect is provided.

As the improvement of the utility model, still be equipped with a plurality of aramid fiber skeletons of arranging around the axis ring of low temperature resistant lag in the low temperature resistant lag. The low-temperature resistant anti-slip sheath has better tensile strength and bending strength, and the anti-shrinkage deformation capability of the low-temperature resistant sheath is strengthened.

The utility model has the advantages as follows:

the utility model discloses a cable sets up the metal covering that has the line of cladding on conductor body and plays better guard action, sets up flexible buffer layer simultaneously between metal covering and conductor body and plays deformation stress cushioning effect, can alleviate high pressure, the phenomenon that fracture and shrink destruction appear easily under great difference in temperature in the superhigh voltage cable.

Drawings

Fig. 1 is a schematic structural diagram of the cable of the present invention.

Fig. 2 is a view of the fitting structure of the metal sleeve and the conductor body of the present invention.

Fig. 3 is a surface structure view of a flexible buffer layer of the present invention.

In the figure, 1, a conductor body, 11, a core wire, 12, a conductor shielding layer, 13, an insulating layer, 14, an insulating shielding layer, 15, a belting layer, 16, a flexible buffer layer, 161, micropores, 2, a metal sleeve, 21, a large-diameter convex ring, 22, a small-diameter concave ring, 3, a low-temperature resistant protective sleeve, 31 and an aramid fiber framework.

Detailed Description

The following further describes the embodiments of the present invention with reference to the drawings.

As shown in figure 1, the temperature-resistant shrinkage crack-resistant cable with the rated voltage of 110kV comprises a conductor body 1 and a metal sleeve 2 covering the conductor body, wherein the conductor body comprises a core wire 11 positioned in the center, a conductor shielding layer 12 covering the core wire, an insulating layer 13 covering the conductor shielding layer, an insulating layer 14 covering the insulating layer, a wrapping layer 15 covering the insulating layer and a flexible buffer layer 16 arranged between the metal sleeve and the wrapping layer, the metal sleeve is an aluminum sleeve, and the wrapping layer is a polyester wrapping tape. The temperature change resistance, shrinkage resistance and cracking resistance of the cable are improved through the arrangement of the metal sleeve and the flexible buffer layer.

In order to improve the defects of unfavorable recycling of thermosetting of the crosslinked polyethylene used by the conventional crosslinked polyethylene insulated cable and high processing cost, the insulating layer is a modified polypropylene insulating layer, the modified polypropylene has higher electrical property, ageing resistance and mechanical and physical properties compared with the crosslinked polyethylene, and the thermoplastic material is convenient to recycle. Furthermore, in order to further enhance the electrical property, the ageing resistance and the mechanical and physical properties of the modified polypropylene layer, the modified polypropylene is a block copolymer obtained by copolymerizing propylene and ethylene and then is mixed with ethylene propylene rubber for granulation to obtain the ultra-clean modified polypropylene insulating material. Meanwhile, the conductor shielding layer, the insulating layer and the insulating shielding layer are prepared in a three-layer co-extrusion mode, and the insulating shielding effect of the cable is enhanced.

In order to strengthen the temperature change resistance, shrinkage resistance and cracking resistance of the cable, the outer side of the metal sleeve is further coated with a layer of flexible low-temperature-resistant protective sleeve 3 which can be made of rubber, the flexible low-temperature-resistant protective sleeve is tightly attached to the surface of the metal sleeve after vacuumizing, an aramid fiber framework 31 is further arranged in the low-temperature-resistant protective sleeve, and the aramid fiber framework is arranged in a circular array mode in the circumferential direction of the low-temperature-resistant anti-slip sleeve.

As shown in fig. 2, in order to further enhance the performance of the metal sleeve, the metal sleeve is formed by connecting a plurality of coaxially arranged annular large-diameter convex rings 21 and small-diameter concave rings 22 in turn, and the adjacent large-diameter convex rings and small-diameter concave rings are connected in a smooth transition manner, so that the metal sleeve forms lines which are sequentially fluctuated in the length direction of the conductor body. In the processing, the lines of the metal sleeve can be obtained by integral pressing and forming. Furthermore, the sections of the large-diameter convex ring and the small-diameter concave ring in the length direction of the conductor body are arc-shaped, the radius corresponding to the arc-shaped section of the large-diameter convex ring is smaller than the radius corresponding to the small-diameter concave ring, and the central angle corresponding to the arc-shaped section of the large-diameter convex ring is smaller than the central angle corresponding to the small-diameter concave ring, so that the arc-shaped section of the small-diameter concave ring is wider and slower than that of the large-diameter convex ring, and larger deformation stress is absorbed.

As shown in FIG. 3, in order to further enhance the performance of the flexible buffer layer, the flexible buffer layer is a polytetrafluoroethylene buffer layer, the polytetrafluoroethylene buffer layer is coated by a polytetrafluoroethylene thick film with the thickness of 2000-300 μm, a plurality of micropores 161 are arranged on the surface and inside of the flexible buffer layer in a dispersed manner, the micropores are distributed in a scattered manner, the sizes of the pores can be different, and the flexible buffer layer is prepared by adding calcium acetate into raw materials and heating and decomposing gas.

Claims

1. The utility model provides a temperature resistant shrink crack's cable of preventing, includes conductor body and the metal covering of cladding conductor body, its characterized in that, conductor body includes heart yearn, the conductor shield of cladding heart yearn, the insulating layer of cladding conductor shield, the insulating barrier of cladding insulating layer, the band layer of cladding insulating barrier and the flexible buffer layer of setting between metal covering and band layer.

2. The temperature-resistant, shrinkage crack-resistant cable of claim 1, wherein the flexible buffer layer has a plurality of discrete micro-pores on its surface and inside.

3. The temperature-resistant, shrinkage crack-resistant cable of claim 1 or 2, wherein the flexible buffer layer is a polytetrafluoroethylene buffer layer.

4. The temperature-resistant shrinkage crack-resistant cable according to claim 1, wherein the metal sheath is composed of a plurality of coaxially arranged large-diameter convex rings and small-diameter concave rings, the large-diameter convex rings and the small-diameter concave rings are in lines which are connected in an up-and-down mode in sequence in the length direction of the conductor body, and the inner side faces of the small-diameter concave rings are tightly attached to the conductor body.

5. The temperature-resistant shrinkage cracking-resistant cable according to claim 4, wherein the sections of the large-diameter convex ring and the small-diameter concave ring in the length direction of the conductor body are arc-shaped, and the radius corresponding to the arc-shaped section of the large-diameter convex ring is smaller than the radius corresponding to the small-diameter concave ring and the central angle corresponding to the central-angle small-diameter concave ring corresponding to the arc-shaped section of the large-diameter convex ring.

6. The temperature-resistant, shrinkage crack-resistant cable of claim 1, wherein the insulation layer is a modified polypropylene insulation layer.

7. The temperature-resistant shrinkage crack-resistant cable according to claim 1 or 6, wherein the conductor shielding layer, the insulating layer and the insulating shielding layer are prepared by a three-layer co-extrusion method.

8. The temperature-resistant, shrinkage crack-resistant cable of claim 1, further comprising a low temperature-resistant protective jacket closely covering the surface of the metal jacket after evacuation.

9. The temperature-resistant, shrinkage crack-resistant cable of claim 8, wherein a plurality of aramid fiber frames are disposed in the low temperature-resistant protective jacket in a circumferential arrangement around an axis of the low temperature-resistant protective jacket.