CN200986826Y

CN200986826Y - High voltage fire-resistant cable

Info

Publication number: CN200986826Y
Application number: CN 200620068200
Authority: CN
Inventors: 梁玉谦
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-11-24
Filing date: 2006-11-24
Publication date: 2007-12-05
Anticipated expiration: 2016-11-24

Abstract

The utility model relates to an improvement of the flame-retardant cable and the utility model particularly relates to a middle and high voltage flame-retardant cable above 6KV. The utility model is characterized in that the core of the enable is constructed by a conductor, a conductor screen, a high voltage insulation, an insulation shielding and a metal shielding. A lapping fire-tight thermal insulation layer and a lapping steel belt thermal insulation layer are arranged between the cable core and the over sheath. The utility model cable cannot only meet the application requirement for high voltage of the cable, but also has the properties of fire retardant and heat insulation as well as high temperature ant vibration. The thermal insulation layer is capable of keeping inner flank temperature below 200 DEG C when the outward temperature is from 800 DEG C to 1000 DEG C. In addition, oxygen in the air can hardly intrude into the cable-insulating layer, therefore any fusion or oxygenolysis can be found in the insulation except softening. Thus the cable is capable of normal operation for more than 120 minibuses at 1000 DEG C on fire, which provides chances for saving.

Description

High voltage flame resistant cable

Technical field

Utility model is about the improvement to fire-resisting cable, relates in particular to a kind of 6KV and above mesohigh fire-resisting cable.

Background technology

The prior art fire-resisting cable, as described in Chinese patent CN93105547.4, its basic structure such as Fig. 1 are made up of conductor 1 wrapped fire-resistant mica layer 2 and assisted plastic insulating barrier 3.Flame retardant coating directly is coated on the conductor outside, certainly exist air gap between the two, partial discharge can take place under high voltage electric field, causing cable insulation to puncture causes scrapping, therefore this structure fire resistance cable can only be used for 1KV and following place, can not be used for the mesohigh of electric pressure higher (more than for example 6KV reaches); Secondly, this structure fire resistance cable after auxiliary insulating layer burns, is easy to cause wrapped mica to drop when catching fire, and loses the hot-face insulation effect, can not guarantee to sue and labour in the back safety of catching fire.

The disclosed high-performance halogen-free flame retardant fire-resisting cable of Chinese patent CN97234805.0, its cable core is made up of conductor, outsourcing mica flame retardant coating, plastic insulation, and between cable core and oversheath, set up mineral complex oxygen barrier layer and nonwoven fabrics band, when taking place, fire can keep cable normally to move to reach at certain hour.Though this cable has increased the mineral complex oxygen barrier layer outside the mica flame retardant coating, the heat that makes fire produce obtains intercepting, but mineral complex oxygen barrier layer outside unprotect has vibration promptly can drop slightly after the ignition of cable baking and loses protective effect, so actual effect is unsatisfactory; Secondly, this construction of cable still can only be used for the low pressure place, and can not be used for mesohigh; Besides,, reduced the cable bending property, made troubles to manufacturing, transport, laying because cable adopts the mineral complex oxygen barrier layer.

Therefore, do not occur 6KV and above mesohigh fire-resisting cable in the prior art so far as yet, especially have the mesohigh fire-resisting cable of bendability.

Summary of the invention

The purpose of utility model is to overcome the deficiency of above-mentioned prior art, and a kind of voltage withstand class height is provided, and hot-face insulation is good, and the high voltage flame resistant cable of good bandability.

The utility model purpose realizes, the main improvement is to increase conductor screen, insulation shielding in the fire-resisting cable cable core, and metallic shield, cable core adopts refractory insulating layer and steel band refuge floor composite fire structure outward, make cable can not only be applicable to 6KV and above mesohigh, and good fire insulation, heat insulation structural, make cable after catching fire, can normally move the long period, and can effectively hang down the anti-process of suing and labouring and vibrate.Specifically, the utility model high voltage flame resistant cable, comprise conductor, flame retardant coating and insulating barrier, and oversheath, it is characterized in that cable conductor is made up of conductor, conductor screen, High-Voltage Insulation, insulation shielding, metallic shield, wrapped refractory insulating layer and wrapped steel band refuge floor are arranged between cable core and oversheath.

The described refractory heat-insulating layer material of utility model, its effect has been the refractory heat-insulating effect, cuts off external high temperature and imports cable inside into, protects the high-voltage insulation layer in it, the mineral fibres bar of the high refractoriness of a kind of preferred employing and be with wrapped composition, for example mineral fibres; Alumina silicate fibre; Polycrystalline mullite fibre; Polycrystalline alumina fiber; Ceramic fibre rope, paper or felt etc. are wrapped.

Said steel band refuge floor, effect are to stop combustion flame to expand the intrusion cable core inwards, and flame is isolated in outside the insulated wire cores, to prolong the cable fire resistance period and to guarantee normal use, guarantee to have in the fire the enough time to sue and labour.Its wrapped steel band according to construction of cable three-core cable, can adopt steel band wrapped, to reduce cable cost; Single-core cable adopts stainless steel band wrapped, avoids using ferromagnetic material to produce the magnetic eddy current and burns out cable.For taking into account cable bending property and fire insulation performance, wrapped steel band should adopt strip bilayer or multilayer gap wrapped.

Oversheath can adopt common cable flame retardant plastics, for example flame-proof polyvinyl chloride, flame-proof polyethylene, halogen-free and low-smoke flame-retardant polyolefin etc.

In addition, for helping production and processing and transportation, lay, a kind ofly preferably between refractory insulating layer and wrapped steel band refuge floor, set up a supporting layer.The supporting layer effect is to bear in wrapped steel band and the use not produce pressure distortion, guarantees the cable rounded configurations, and refractory insulating layer is loose not compacted, helps keeping cable performance and good effect of heat insulation.Said supporting layer, but a kind of better be to adopt the hot extrude bag, the polyethylene of cooling back good rigidly is preferably high, medium density polyethylene, its thickness is according to the cross-section of cable and the decision of cable core number, the cross-section of cable is big, the core number is many, supporting layer is suitable thick.

The utility model high voltage flame resistant cable, owing to outside the cable core conductor, increase conductor, insulation shielding, and metallic shield, thereby can satisfy the instructions for use of cable mesohigh; Outer refractory insulating layer of cable core and wrapped steel band refuge floor composite fire structure, not only back-fire relief, heat-proof quality are good, the 800-1000 ℃ of high temperature in thermal insulation layer outside, can keep inboard temperature to be lower than 200 ℃, and oxygen is difficult to invade cable insulation in the air, and insulation only can be softened, and can not melt, more can not produce oxidation Decomposition, thereby effectively protect the not insulating barrier normally use in a long time of heatproof; And high temperature vibration-proof is strong, can guarantee that 1000 ℃ are normally moved more than 120 minutes behind the ignition of cable, sues and labours after guaranteeing to catch fire.The utility model cable, not only cable voltage grade height, and cable fire resistance improves greatly, can be used for 6KV and above mesohigh, and missing of ignition normal operating conditions can keep the medium and high voltage cable operating characteristic of same levels.

Below in conjunction with two optimization execution modes, further specify utility model.

Description of drawings

Fig. 1 is prior art kilovolt level and following fire-resisting cable structural representation.

Fig. 2 is utility model three core high voltage flame resistant cable structural representations.

Embodiment

Embodiment 1: utility model three core high voltage flame resistant cables, thoroughly do away with the edge core by three and form cable core, fill adiabatic refractory fibre 8 during stranding, wrapped successively outward adiabatic refractory fibre band 9, wrapped thickness is greater than the refractory insulating layer 10 of 10mm, extrude polyethylene supporting layer 11, the wrapped double-deck steel band refuge floor 12 in gap has flame retardant plastics sheath 13 outward.Insulated wire cores is by compact conductor 1, semiconductive crosslinked polyethylene conductor screen 4, and crosslinked polyethylene High-Voltage Insulation 5, the crosslinked polyetylene insulated shielding 6 of semiconductive, metallic shield 7 is formed.

Embodiment 2: the single core high voltage flame resistant cable of utility model, as described above, cable core is made up of single insulated wire cores, omits and fills adiabatic refractory fibre 8 and adiabatic refractory fibre band 9, it is wrapped that the fire insulation steel band changes the double-deck gap of stainless steel band into, produces the magnetic eddy current and the scaling loss cable when preventing to switch on.

Claims

1, high voltage flame resistant cable, comprise conductor, flame retardant coating and insulating barrier, and oversheath, it is characterized in that cable conductor is made up of conductor, conductor screen, High-Voltage Insulation, insulation shielding, metallic shield, wrapped refractory insulating layer and wrapped steel band refuge floor are arranged between cable core and oversheath.

2,, it is characterized in that said wrapped refractory insulating layer is made of the mineral fibres bar and the band of high refractoriness according to the described high voltage flame resistant cable of claim 1.

3,, it is characterized in that said wrapped refractory heat-insulating layer thickness is greater than 10mm according to claim 1 or 2 described high voltage flame resistant cables.

4,, it is characterized in that said wrapped steel band refuge floor is that strip bilayer or multilayer gap are wrapped according to the described high voltage flame resistant cable of claim 1.

5,, it is characterized in that between refractory insulating layer and wrapped steel band refuge floor supporting layer being arranged according to claim 1,2 or 4 described high voltage flame resistant cables.

6,, it is characterized in that said supporting layer is for extruding polyethylene according to the described high voltage flame resistant cable of claim 5.

7,, it is characterized in that said polyethylene is high, medium density polyethylene according to the described high voltage flame resistant cable of claim 6.