Low-smoke halogen-free flame retardant cable material

In China, many companies have carried out research and development of low-smoke, halogen-free flame-retardant cable material technology, which has promoted the development of the low-smoke halogen-free flame-retardant cable material market, and has also achieved some results.
In 2004, Beijing University of Chemical Technology successfully developed high-performance halogen-free flame-retardant cable material technology. It was the first time in China that a new method for synergistic flame-retarding of nano-magnesium hydroxide with low-filling and red phosphorus and two different surface-treated micron hydroxides were used. Combined use of magnesium technology, the material has high strength, high flame retardancy, good fluidity, good heat resistance and other excellent overall performance, performance indicators reached the advanced level of similar products of the same time at the time, breaking the passive situation of imported products monopolized the domestic market.
The halogen-free flame-retardant cable material successfully developed by Beijing University of Chemical Technology can be comparable in performance to imported products at the time, but the price is lower than that of imported products. It can save raw material costs of 3,000 to 5,000 yuan per ton for cable manufacturers, which is extremely strong. Market competitive advantage.
In recent years, with the development of flame-retardant technology for cable materials, new types of flame-retardant cables have also been produced. In Europe, America and Japan, environmental protection wire and cable has become the main product of all cable types. The government strictly prohibits the use or import of non-environmental cables. Common flame-retardant materials contain a large amount of halogen, which will produce a lot of smoke and toxic corrosive hydrogen halide gas when burning. Halogen-free flame retardant is mainly chosen to be realized in polyolefin, so low-smoke halogen-free cable will be In the future, the main trend of development will be discussed in the following aspects: Extrusion of low-smoke halogen-free cable materials.
1, extrusion equipment
(1) The main component of the wire and cable extrusion equipment is the screw, which relates to the application range and production efficiency of the extruder. In order to meet the needs of different plastic processing, there are many kinds of screw types. Low-smoke halogen-free flame-retardant cable material contains high-filled magnesium hydroxide or aluminum hydroxide, so the general selection of the screw for the general use of the screw and its compression ratio can not be too large, generally 1:1 to 1 : 2.5 is more appropriate.
(2) There is also an important factor affecting the extrusion of low-smoke halogen-free cable material in the extrusion process. That is the cooling device of the extruder. Because of the special characteristics of the low-smoke halogen-free material, friction occurs during the extrusion process. The generation of large heat, which requires the extrusion equipment to have a good cooling device, can control the process temperature. This is a problem that cannot be ignored. If the temperature is too high, the surface of the cable will have large pores. If the temperature is too low, the whole current of the device will increase, which will easily damage the device.
1, low technology
The technical level of China's wire and cable materials has always been a big gap with foreign countries. In the early 1980s, many manufacturers in the cable industry in China successfully developed general flame-retardant cables. According to statistics, from 1987 to 1991, more than 40 kinds of flame-retardant cables have been trial-produced. Basically, flame-retardant PVC and flame-retardant neoprene are basically used. This kind of flame-retardant cable is only suitable for occasions with low flame retardance requirements, and for some resistances For special occasions with higher burning level requirements, low-smoke and halogen-free flame-retardant cables are required, such as underground public facilities, high-rise buildings, ships, warships, and so on. Due to low technology, our country has low production capacity. Most of the Imported from abroad to meet the demand, and foreign technology through the monopoly, low-smoke halogen-free flame retardant cable material prices are very high at 25,000 yuan / ton -35,000 yuan / ton, making China pay a high price.
2, limited application area
Low-smoke, halogen-free flame-retardant cable material is the development direction of China's cable materials because of its environmental protection and social requirements. However, the application fields of low-smoke halogen-free flame retardant cable materials in China have so far been limited. They are mainly used in metros in large cities. Areas such as city rails, ships, high-rise buildings, and nuclear power stations are used in developed provinces and cities such as Beijing, Shanghai, Guangzhou, Xi’an, and Shandong. They are rarely used in many remote areas and are far from popular.
3, broad prospects
As a "green cable" - halogen-free flame-retardant cable has a broad market prospects.
China's domestic wire and cable annual output accounts for about 20% of the world's total production. According to the output value, it accounts for approximately 15% of the world's total wire and cable output value, which is approximately 80 billion yuan (RMB). China has developed into the world's largest wire and cable market. With the development of society, people are paying more and more attention to environmental issues. Many countries have already formulated various environmental protection policies. For example, the EU-developed ROHS Directive: From July 1, 2006 onwards, new electronic appliances will be put on the market. In equipment, the use of harmful substances such as lead, mercury, cadmium, hexavalent chromium, polybrominated diphenyl ether (PBDE), and polybrominated biphenyls (PBB) is prohibited. Among them, PBDE and PBB are mostly used for flame retardants in plastics. Japan's major electrical companies have also formulated corresponding requirements. Since March 2006, various electrical appliances have been required to use halogen-free wires and cables. Therefore, halogen-free flame-retardant wire and cable has become an important development direction of the industry. In China, with the increasing emphasis on the environment, halogen-free flame-retardant products have become more widely used. For example, in the home appliance industry, building materials, telecommunications, automotive and other industries, halogen-free flame-retardant wire and cable have a great deal of demand. In terms of electrical appliances, China has become the world’s largest producer of electrical appliances and the world’s largest exporter of electrical appliances, taking into account the “technical barriers” of disguised restrictions imposed by some countries on the import of halogen-containing products, so halogen-free flame-retardant wire and cable There is a very large application prospect in the home appliance industry. There are already regulations in the country requiring high-rise buildings to use halogen-free flame-retardant wires and cables. In addition, the requirements for halogen-free are added to the flame-retardant basis for telecommunication infrastructure equipment and automotive wires. In summary, both halogenated and non-halogenated are the development direction of flame-retardant wire and cable, and the market prospects are very high. Broad, with great market potential.
In China, many companies have carried out research and development of low-smoke, halogen-free flame-retardant cable material technology, which has promoted the development of the low-smoke halogen-free flame-retardant cable material market, and has also achieved some results.
In 2004, Beijing University of Chemical Technology successfully developed high-performance halogen-free flame-retardant cable material technology. It was the first time in China that a new method for synergistic flame-retarding of nano-magnesium hydroxide with low-filling and red phosphorus and two different surface-treated micron hydroxides were used. Combined use of magnesium technology, the material has high strength, high flame retardancy, good fluidity, good heat resistance and other excellent comprehensive performance, performance indicators reached the advanced level of similar products of the same time at the time, breaking the passive situation of imported products monopolized the domestic market.
The halogen-free flame-retardant cable material successfully developed by Beijing University of Chemical Technology can be comparable in performance to imported products at the time, but the price is lower than that of imported products. It can save raw material costs of 3,000 to 5,000 yuan per ton for cable manufacturers, which is extremely strong. Market competitive advantage.
At present, China's flame-retardant wire and cable products are mainly halogen-containing flame-retardant. This type of wire and cable emits a large amount of smoke and corrosive halides when it is burned, causing casualties and corrosion of various equipment, the so-called "secondary disasters." ". In order to achieve low smoke, low toxicity and flame retardant, many domestic and foreign manufacturers are committed to the development of low smoke, low halogen, low smoke, halogen-free flame retardant materials. When these materials burn, they emit less smoke and emit less toxic gases, reducing damage to the human body and equipment. Developed countries in foreign countries have relatively early research on low-smoke, low-halogen, low-smoke halogen-free flame-retardant wire and cable materials. The technology is relatively mature and has now entered a practical stage. The research and development of low-smoke, low-halogen, and low-smoke halogen-free flame retardant wire and cable materials in China is relatively late. At present, the research on low-smoke halogen-free flame retardant wire and cable materials in China is still in its infancy. Some manufacturers have produced low-smoke products. Halogen-free flame-retardant wire and cable materials, but most of them have problems with poor mechanical properties and poor processability.
Flame-retardant wire and cable can generally be divided into general flame-retardant wire and cable, low-smoke low-halogen flame-retardant wire and cable, and low-smoke halogen-free flame-retardant wire and cable At present, China's low-smoke halogen-free flame-retardant wire and cable materials rely mainly on imports, the price is high, and the application is subject to certain restrictions. With the rapid development of China's economic construction, the demand for safety performance is increasing, the demand for low-smoke halogen-free flame-retardant wires and cables is increasing, and many domestic manufacturers have increased efforts to carry out low-smoke halogen-free flame retardant wire and cable materials. Development. In 2002, the Ministry issued the mandatory standard GA306-2001 "Flame-Retardant and Fire-Resistant Cables: Grades and Requirements for Plastic Insulated Flame-retardant and Fire-Retardant Cables" to classify fire-resistant cables and the smoke and smoke of fire-resistant cables. Toxicity made specific provisions to further improve China's standard system of flame-retardant and fire-resistant cables, to promote and apply flame-retardant, high-efficiency, pollution-free flame-retardant, fire-resistant cables play a promoting role. Starting in 2000, China's cable supply was in short supply, and some products even appeared out of stock. There are nearly 5,000 wire and cable manufacturers in China. Because of the huge demand for wire and cable products due to the transformation of urban and rural power grids, Western Development, and the large-scale upgrade of the Sanhe project and communication facilities, cable materials have a wide market prospect in China for a period of time. In the early 1980s, low-smoke halogen-free flame retardant cable materials have been developed abroad. By the late 1980s, the second generation of halogen-free flame retardant plastics for wire and cable had been developed. Compared with the first generation of products, the second-generation non-halogen flame-retardant plastics are not only improved in flame retardancy, smokeability, toxicity, corrosion performance, mechanical properties, and electrical properties, but also exhibit high-speed extrusion performance. feature.

I. High & Low voltage cabinets installation of power plant

1. 10KV high voltage switch cabinet installation of power plant

2. 0.4KV low voltage switch cabinet installation of power plant

3. Installation of generator protection system, synchronization system, transformer protection, H.V. motor protection, circuit protection in a power plant.

II. Electrical configuration testing items of power plant

1. Vacuum circuit breaker insulation resistance measurement, each phase circuit resistance measurement and AC voltage withstand tests of 10KV H.V. switch cabinet.

2. DC resistance measurement of CT and PT, polarity test, ratio test, AC voltage withstand tests in 10KV H.V. switch cabinet.

3. AC voltage withstand tests for whole 10KV H.V. switch cabinet.

4. AC resonant test for 10KV H.V. electric cable.

5. DC resistance measurement of generator stator and rotor.

6. Generator stator coil insulation resistance measurement and DC voltage withstand tests.

7. Generator rotor insulation resistance measurement.

8. Generator rotor AC impedance and power loss tests.

9. No-load characteristic test of generator

10. Generator checking phase sequence (fist checking phase and second checking phase separately).

11. Generator short circuit characteristic test.

12. Measurement of residual voltage of stator after automatic magnetic blow-out and switch opening of generator.

13. Generator shaft voltage measurement.

14. Generator simulate synchronization.

15. All of the second circuit checking, measuring, switch tripping & closing tests, protection fixed value setting, protecting the STG trip test and magnetic blow-out tripping test for Steam Turbine and generator.

III.Electrical problem troubleshooting in power plant

Problem Description: a coal mine`s 35KV H.T. switchgear OC protection tripped suddenly in He`nan Province, it caused sudden power lost of mine fan and endanger miner safety.

Auto-reclosing via switchgears` automatic reclosing function, through analysis, the reason is a set of 3000KW generator failure. Specific reason is: When the turbo-generator was running normally, exciting voltage lost suddenly, leading phase operation happened, the generator absorbed reactive power and lead to becoming motor running. Generator protection and power plant connecting line protection did not launch. After the generator absorbed a certain value of reactive power, the 35KV H.T. switchgear`s OC protection tripped.


Investigation: generator and power plant connecting line protection setting fixed value exceed the protection fixed value of 35KV switchgear side, it lead to nearby protection did not launch and override trip when generator failure.

Electrical Cabinet Care

Electrical Cabinet Care,10Kv Electrical Cabinet Care,0.4Kv Electrical Cabinet Care,Electric Governing Reconstructing

Shandong Qingneng Power Co., Ltd. , https://www.steamturbine.be