Fire Resistant Cable
Fire resistant cables are cables that are able to maintain safe operation for a certain period of time in the presence of burning flames. That is, to maintain the integrity of the circuit, this type of cable has the ability to supply power for a certain period of time in the flame. General fire-resistant cable in the 750 ~ 800 ℃ flame burning to maintain normal operation for 180 minutes. Fire-resistant flame-retardant cable combustion produced by the amount of acid gas smoke is small, fire-resistant flame-retardant performance is greatly improved, especially in the case of combustion, accompanied by water showers and mechanical strikes vibration, the cable can still maintain the integrity of the circuit operation.
Use conditions
1. AC rated voltage: U. / U (V series: 600/1000V, K series: 450/750V, B series: 450/750V).
2. Maximum long-term working temperature of the cable:
(1) alkene-resistant polyfluoroethylene insulation and sheath: 70℃ and 105℃ both; cross-linked polyethylene insulation: 90℃;
(2) Fluorine plastic insulation and sheath: 220 ℃ and 260 ℃ two; fluorine plastic insulation and 105 ℃ flame retardant polyfluoroethylene sheath: 90 ℃ and 125 ℃ two;
(3) Low-halogen, low-smoke flame-retardant PVC insulation and sheath: 70℃; halogen-free, low-smoke flame-retardant polyolefin insulation and sheath: 90℃ and 125℃.
3. Minimum ambient temperature:
(1) Flame retardant PVC insulation and sheath: fixed laying -40℃; non-fixed laying -15℃;
(2) fluorine plastic insulation and sheath: fixed laying -60 ℃; non-fixed laying -20 ℃.
4. The safe laying temperature of the cable should not be lower than 0℃.
5. Fire resistance characteristics:
Comply with GA 306.2-2007, GB/T 19216.21-2003.
Flame Temperature Flame Temperature 950℃-1000℃ Flame Temperature 750℃-800℃
Burning time Burning time 90min (recommended) Burning time 90min (recommended)
Additional voltage Rated voltage (min. 100V) Rated voltage (min. 100V)
Fire Resistance Class A (Class IA~IVA) Class I~IV
6. Laying the recommended permissible bending radius: non-armoured, braided shielded cable shall be not less than 6 times the outer diameter of the cable;
Steel tape armoured cable shall be not less than 12 times the outer diameter of the cable;
Fluorine plastic insulation and sheath material cable should be not less than 8 times the outer diameter of the cable.
NO.1, Jiangnan Cable has advanced production technology and equipment. From the manufacturing of conductors to the processing of insulation, shielding and sheathing, every step is precise and strict to ensure the high quality of medium voltage cables.
NO.2, the quality control is extremely strict. The company has established a perfect quality inspection system, from the selection of raw materials to the finished products leaving the factory, checking at every level. Each medium-voltage cable has to go through a number of strict tests to ensure that the products meet or even exceed the national standards.
NO.3, Jiangnan Cable has invested heavily in research and development. According to the market demand and customers' special requirements, we can develop medium voltage cables with different characteristics, such as better environmental resistance and better current carrying capacity. Moreover, the rich product line can meet the different needs of various complex projects and provide customers with one-stop cable solutions.
Our Cases
what we finished
| Customized | Cable Specifications | Insulation Material | Shield Construction | Sheath Material | Armor Structure | Special Performance | Length | ||||||||
| Conductor Cross Section | Number of cores | Material Type | Insulation Thickness | Shielding type | Number of Shielding Layers | Material Selection | Color Identification | Armor type | Armor Layers | Fire resistance | Waterproof performance | Flame retardant performance | Cold resistance | Sample customization request meters | |
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Structural characteristics
Fire-resistant cable structure and ordinary cable is basically the same. The difference is that the conductor of the fire-resistant cable is made of copper wire with good fire-resistant performance (the melting point of copper is 1083℃), and a fire-resistant layer is added between the conductor and the insulation layer. The refractory layer is made of multi-layer mica tape. Since the allowable working temperature of different mica tapes varies greatly, the key to determining the fire resistance of the cable is the mica tape.
Fire-resistant cables have good fire-resistant characteristics and can work under the high temperature of 250℃ for a long time, as well as explosion-proof, corrosion-resistant, high current-carrying capacity, radiation-resistant, high mechanical strength, small volume, light weight, long life, and smoke-free.
Fire-resistant cable according to the national experimental standards (GB12666-99) can be divided into two classes: NHA, NHB; in the general product naming, NHA is usually expressed in GNH, the genus called high fire-resistant cables.NHB in the general fire-resistant products, expressed in NH.
Category B cables are able to withstand combustion in a flame of 750 ℃ ~ 800 ℃ and rated voltage for at least 90min without the cable being struck (i.e., 3A fuse does not blow).
In improving the fire-resistant layer manufacturing process and increase the fire-resistant layer and other methods based on the development of a class A fire-resistant cable, which can withstand combustion in the flame at 950 ℃ ~ 1,000 ℃ and rated voltage for at least 90min and the cable is not broken (that is, 3A fuse does not blow).
The fire-resistant performance of Class A fire-resistant cables is better than that of Class B. In addition, mineral insulated cables are fire-resistant cables in a better performance, it is processed from the copper core, copper sheath, magnesium oxide insulation materials, referred to as MI (mineral insulated cables) cable. The cable is entirely composed of inorganic materials constitute a fire-resistant layer, while the fire-resistant layer of ordinary fire-resistant cables is composed of inorganic materials and general organic composite, so the fire-resistant performance of MI cables is better than ordinary fire-resistant cables and will not be decomposed due to combustion of corrosive gases. MI cables have good fire-resistant properties, can work for a long time at a high temperature of 250 ℃ under the fire-resistant properties of MI cables, as well as explosion-proof, corrosion-resistant, high current-carrying capacity, radiation-resistant It is also explosion-proof, corrosion-resistant, high current-carrying capacity, radiation-resistant, high mechanical strength, small size, light weight, long service life, and smoke-free. But the price is expensive, complex technology, construction difficulties, in the oil irrigation areas, important wooden public buildings, high temperature places and other fire-resistant requirements of high and acceptable economic occasions, can be used in this fire-resistant performance of the cable.
Fundamental characteristics
The cable can still maintain the normal operation of the line for a period of time under burning conditions. In layman's terms, in case of fire, the cable will not burn at once, the circuit is safer.
Basic Function
Fire-resistant cable is made of copper and other metals as conductor and insulating materials as component parts, which make the conductive part and the non-contact part closely contact and form a whole with certain strength through insulation and protective sheath, so that the conductive part maintains a certain degree of stability in the whole fire environment.
Advantages
1. In case of fire, the amount of smoke is less, which buys time for people fleeing from the scene;
2. Excellent flame retardant properties, fire-resistant wire can ensure that the line in the event of a fire in a certain period of time to normal power, transmission of a variety of control signals, alarm signals, so the product has a certain period of time in the flames of the power supply capacity;
3. The copper sheath itself is a good grounding wire, so it can be a good guarantee of personnel safety;
4. have good corrosion resistance, generally do not need special protective measures. Unless it is in the place of serious chemical corrosion, plastic sheath can be used to protect the copper sheath;
5. The whole of the fire-resistant cable is made of inorganic materials, so the whole fire-resistant wire is neither easy to burn nor delayed combustion;
6. The cable adopts seamless copper sheath, even if it is immersed in water, it can be energised for a long time to run, and it is waterproof;
7. Compared with other models with the same core cross-section, fire-resistant cables can run continuously for a long time, with high current-carrying capacity and strong overload capacity.
It is the special advantages of fire-resistant cable, destined to fire-resistant cable in the fire requirements of a wide range of places, such as: fire pumps, fire alarm system manual alarm line, high-rise buildings or airports, underground and other places. It is not difficult to see that, with the development of modern industry, the advantages of fire-resistant cable will make it occupy an irreplaceable position in the wire and cable industry.
Scope of application
Fire-resistant cables are able to maintain normal power supply for a period of time in the event of a fire. This characteristic determines that fire-resistant cables play an important role in modern urban and industrial buildings, because in the event of a fire, the power supply circuits of the control, monitoring, guiding and alarm systems must be maintained in order to work properly. Therefore, they are mainly used in the supply circuits from the emergency power supply to the user's fire-fighting equipment, fire alarm equipment, ventilation and smoke extraction equipment, guiding lights, emergency power sockets, and emergency lifts.
Application
1. Power supply line and control line of fire pump, sprinkler pump and fire lift;
2. The power supply and control lines of fire shutter door, electric fire door, fan of smoke prevention and exhaust system, smoke exhaust valve and fire damper;
3. Manual alarm lines of fire alarm system, fire broadcasting and telephone lines;
4. security closed-circuit television lines in high-rise buildings or important facilities such as airports and subways;
5. Centralised emergency lighting lines, control and protection power lines;
6. Important relay protection lines and operation power lines in large and medium-sized power substations and distribution centres;
7. Computer monitoring lines.
Fire-resistant time
Fire-resistant cables are suitable for particularly important occasions of 1KV and the following power or control system lines, when the line in case of fire, fire-resistant cables can resist 750-800 ℃ high temperature of more than 90 minutes, to ensure the safety of power supply, in order to win enough time to extinguish and reduce the fire. Therefore, the cable is widely used in petrochemical, metallurgy, high-rise buildings and other important places. Fire-resistant cables are divided into two categories, A and B. The high temperature of A category is as high as 950-1000℃, and B category reaches 750-800℃, and B category is usually chosen, which is indicated by NB or NH.
1.IEC60331-1999, the fire temperature requirements for 750 ℃ / 3h level, that is, at 750 ℃ under the level of 300 volts applied to burn 3 hours without breakdown.
2.BS6387 requirements through the horizontal combustion test, water spray test and mechanical shock vibration combustion test.
Horizontal combustion test for A level 650 ℃ / 3h, B level 750 ℃ / 3h, C level 950 ℃ / 3h and S level 950 ℃ / 3min.
Class A indicates that it does not break down after 3 hours of horizontal burning at 650°C with 300 volts applied;
Class B indicates no breakdown after 3 hours of burning at a voltage level of 300 volts applied at 750℃;
Class C indicates no breakdown after 3 hours of burning at 950℃ with 300V applied;
Class S indicates no breakdown after 3 minutes of burning at 950℃ with 300V applied.
The water spray combustion test is divided into W level, which indicates that it does not break down after applying 300V for 15 minutes and then water spray combustion for 15 minutes.
The shock and vibration burning test is divided into X class 650℃/15min, Y class 750℃/15min and Z class 950℃/15min.
Class X indicates that the mechanical shock vibration is applied at 650℃ for 15 minutes without breakdown while burning at 300 volts every 30 seconds;
Class Y indicates no breakdown at 750°C for 15 minutes with mechanical shock vibration every 30 seconds while burning at 300 volts;
Class Z means no breakdown by mechanical shock vibration for 15 minutes at 950°C with 300 volts applied for 30 seconds while burning.
BS6387 requires the highest level of type CWZ.
Fire-resistant wire and cable is a general term for wires and cables with fire-resistant properties, which are usually divided into two categories: flame-retardant wire and cable and fire-resistant wire and cable. The general public is very easy to confuse the concept of flame retardant cables and fire-resistant cables, although the flame retardant cables have many advantages that are more applicable to the chemical industry, such as low halogen, low-smoke flame retardant, etc., but in general, the fire-resistant cables can replace the flame retardant cables, while the flame retardant cables can not replace the fire-resistant cables.
1. Difference in principle
The principle of fire-resistant cable is different from that of flame-retardant cable. Halogen-containing cable flame retardant principle is to rely on the halogen flame retardant effect, halogen-free cable flame retardant principle is to rely on the precipitation of water to reduce the temperature to extinguish the fire. Fire-resistant cables rely on the fire-resistant layer of mica materials in the fire-resistant, heat-resistant properties, to ensure that the cable in the fire also work properly. The current representative fire-resistant cable in the ceramic cable, as an emerging technology, it is the principle of such cables in the flame can form a self-supporting ceramic body, has a certain strength, thermal shock resistance and good electrical properties, in the flame at a high temperature of 650 ~ 1000 ℃, a certain period of time (0.5 ~ 2h) within the structural integrity of the cable can be very well play the role of the "Passive fire prevention" effect, for fire safety to win valuable time. And it has the characteristics of non-halogen, low smoke, low toxicity, self-extinguishing, environmentally friendly, easy to process.
2. Difference in structure and material
Fire-resistant cable and flame-retardant cable are also different in structure and material.
The basic structure of flame retardant cables is: the insulation layer is made of flame retardant materials, the sheath and outer sheath are made of flame retardant materials, and the wrapping and filling are made of flame retardant materials.
The fire-resistant cable is usually between the conductor and insulation layer and then add a fire-resistant layer, so theoretically you can add a fire-resistant layer in the structure of the flame-retardant cable, the formation of both flame-retardant and fire-resistant cables, but in practice there is no need for this. Because the fire-resistant layer of the fire-resistant cable, usually can use different fire-resistant materials directly covered in the wire. It can withstand a long period of combustion, even if the polymer is burned at the place where the flame is applied, but also to ensure the normal operation of the line.
Most of the fire-resistant cables are flame-retardant cables, and the main difference between fire-resistant cables is that fire-resistant cables can maintain normal power supply (use) for a period of time in the event of a fire, while flame-retardant cables do not have this characteristic.
Fire-resistant cable refers to: under the specified test conditions, the specimen is burned in the flame, within a certain period of time can still maintain the normal operation of the performance.
The fundamental characteristic is: the cable in the burning conditions can still maintain the line for a period of time of normal operation. In layman's terms, in case of fire, the cable will not burn at once, the circuit is safer.
Fireproof cable is characterised by neither combustion nor delayed combustion; it is made of special materials, seamless copper tube as the sheath, magnesium oxide as the insulating material for the production of highly efficient fireproof cable, the common models are BTLY, YTTW, BBTRZ, HFTGB, BBTZ and so on. Experiments have shown that: in 800 ~ 900 ℃ in 2 hours, fire wire and cable is still normal operation, in 1000 ℃ in 30 minutes still continue to operate normally. But the cost is relatively expensive, and does not have the usual cable flexibility. Currently in civil construction is mainly used to ensure personal and property safety in important places of special loads.
