【 Weak current College 】 large iron and steel enterprises fire system analysis---Power By 【 China power house network 】

Summary for metallurgical enterprises of hydraulic station, lubrication station, cable tunnels, electrical hazards such as basement area, this article first on these parts do fire risk analysis, on this basis, a set of reasonably complete fire protection systems, including automatic fire alarm system, automatic fire extinguishing system selection, as well as fire sealing system requirements to ensure the safety of production in these regions. Keyword steel fire cables hydraulic station 1. The preamble along with advances in technology and the development of iron and steel industry, steel companies of scale in increased year by year, modern level continues to improve. At present, China has become the world's largest steel producer, in 2005 the steel output reached 3.49 billion tons, an increase of 24.6%, China's steel output has accounted to the world steel output of 30 per cent, and the second, third and fourth in total. Estimated 06 years China's steel output will increase by 40 million tons, total production close to 4 million mark. Iron and steel industry has become since reform and opening up development and change one of the most significant industry, on the national economy plays an important role. However many large-scale iron and steel enterprises fire and various small and medium-sized fire accident but give business managers, project designers, fire supervision departments forward alert, enterprises of fire safety situation is not optimistic. In May 1997 a steel plant roughing mill area control cabinet bottom cable smoke, fire, the fire spread rapidly along the cable tunnel, the fire resulted in the loss of approximately $ 200 million directly; in 1998 of a steel plant steel cable tunnel in case of fire, and rapid spread, resulting in the electrical equipment burnt, indirect losses of millions, the fire was caused by the Asian steel market price fluctuation; in mid-April of this year a steel works, steel works, because the water leakage, fire ignition cables along the cable tunnel, shaft fast spreading, direct burning of all high-voltage distribution Cabinet, the loss of nearly 6 billion, down for 12 days. The occurrence of these fire case fully illustrates the iron and steel metallurgy enterprises of the fire protection design is the problem. On metallurgical enterprises, lubrication of hydraulic station, underground stations, depots, cable tunnels, electrical fire in the basement are the most vulnerable and spread of parts, and the fire is very difficult to implement effective suppression, so these parts of the fire protection system of the allocation becomes even more important, the following will be further detailed analysis. 2. iron and steel enterprises in fire risk analysis 2.1 underground hydraulic and lubrication station hydraulic and lubrication station is stockpiling of hydraulic oil, lubricating oil and other flammable liquids r main site of the oil equipment and pipelines and pipeline fittings for sealing is not strict, and other factors often lead to oil leaks, once the fire source, easily flowing fire. High pressure hydraulic pipeline due to its ageing and other reasons, lead pipe rupture, high speed spray out of the oil mist, once the fire source, easily cause Jet fire, and could lead to fire spread, is expanding rapidly. In addition, in hydraulic and lubrication station often have cable tray through, so there is a risk of electrical fires. In short, the hydraulic and lubrication station at oil and electrical fire, such as composite and render three-dimensional characteristics of fire. Hydraulic and lubrication station General in underground, unattended, space is relatively large, the fire spread rapidly, and public fire-fighting hard to play. In sum, the hydraulic and lubrication station there is great danger of fire, the fire danger for r and electrical engineering. 2.2 cable tunnels and electrical basement in metallurgical industry, wire, cable throughout the entire process. Wire and cable insulation from the conductor, and protection layers, is used to transport electricity, information and achieve electromagnetic energy conversion of electrical products. Wire, cable, to a certain working conditions are safe to run, but when its in overload, short-circuit, local overheating, aging, such as a failed State and thermal effects easily lead insulation insulation resistance loss, loss of insulation capacity, even burning, and cause a fire or explosion. The main reasons are: (1) cable fire spread burning equipment: underground cables, and the top of the control cabinet, distribution box via a cable connection. The current use of metallurgical enterprise distribution Cabinet, control cabinet equipment is mainly made of imported products, the equipment is expensive, have an important impact on production, if burned, causing large cut-off, bring incalculable indirect losses. If you cannot identify and take measures so that the fire spreading to adjacent control room, rolling lines, hydraulic station, etc., will be more serious accidents. (2) smoke diffusion: cable fire will produce a lot of smoke and toxic gas, corrosion damage electrical equipment, and very harmful to human health. (3) fire-fighting troops to implement effective: underground cables and cable tunnel fire after a large amount of heat and smoke is harmful to human beings, it is difficult to enter the fire forces take control measures. Conventional fire-fighting measures such as fire extinguishers, water gun and other equipment is very difficult to reach the ground, the fire extinguishing effect is greatly reduced, only let it burn. (4) chimney effect: in cable tunnels, underground cable room ventilation shaft Department in the event of fire, and also produces the chimney effect, enables the rapid spread of fire. 3. automatic fire alarm system design analysis under existing national norms, material combustion, fire risk analysis, to not do fire of underground cables, cable dissection, hydraulic, lubrication station adopts single circuit analog temperature sensor cable; cable to do the fire tunnel, underground cables, cables with mezzanine with single-circuit analog temperature sensor cable laying and smart point-type thermal detectors; do fire of hydraulic station, lubrication station adopts single circuit analog temperature sensor cable and multi-frequency dual-band infrared Flame detectors. 3.1 choice analysis of temperature sensor cable for iron and steel metallurgy industrial environment very bad, its protection establishments often exist a large number of electromagnetic radiation, dust, dust, grease and corrosive gases, etc., some of these establishments also have high temperature, high humidity and vibration noise was so loud and so on. General's probe, due to special circumstances, a antijamming ability and original design, the application wouldn't be long proved most harsh environments for running tests. But restorable analog linear heat detector of well solved in iron and steel metallurgy industrial environment other detectors difficult to achieve high reliability, stability, and timeliness, alarm and significantly reduces the fault and false positives. Restorable analog line type heat detector with: ① sensitive components can be reused; ② action temperature and adjusts the sensitivity can be set; ③ two-circuit, short circuit fault alarm; ④ Detector sensitivity with the sensitive element heating lengthIncreased; ⑤ sensitivity than digital high; ⑥ packaging, transport, installation does not have special requirements, the ability to resist mechanical damage is very strong; ⑦ metal braided shield, resist all kinds of great capacity of electromagnetic interference. Therefore in foreign countries and domestic iron and steel metallurgy enterprises has been widely used and successful prediction initial fire, avoiding and reducing cases of economic loss. Therefore, the State of the automatic fire alarm system design code (GB50116-1998) section 7.3.2 stipulates: cable tunnel, sandwich, and other conditions of the site to select cable-style fixed temperature probes; in the iron and steel metallurgy enterprises design fire protection standard law (approval) section 7.1.1 of cable tunnels, underground cables, cable dissection, hydraulic, lubrication station should use or use linear heat detector. 3.2 select infrared Flame detectors of hydraulic station, lubrication station and Depot with lots of oil pollution, poor conditions. Oil combustion process quick, strong flame radiation multi-frequency dual-band infrared flame detector with high sensitivity, protected area, convenient installation, dustproof and waterproof, especially for welding, sunlight, artificial light, thermal and mechanical vibration and other environmental has strong anti-jamming performance, therefore, are widely used in iron and steel enterprises. But other types of detectors such as smoke, warm feeling in this type of fire environment, the response is slow, unreliable. Therefore, the State of the automatic fire alarm system design code (GB50116-1998) section 7.2.7 stipulates that there is a strong fire flame of places to choose flame detector; in the iron and steel metallurgy enterprises design fire protection standard law (approval) section 7.1.1 of hydraulic station, lubrication station to choose point-type flame detector, to make water mist, the selection of single circuit analog temperature sensor cable and flame detector combination detection. 4. automatic fire extinguishing system design of the iron and steel metallurgy enterprises design fire protection standard law (approval) table 8.1.5: table 1 building (structure) to build and process facilities of fixed fire extinguishing systems fire extinguishing media setting requires building area ＞ 500m2 cable dissection and electric basement; main building and the important public assisted area of the cable tunnel (Gallery) road water spray, water mist fire protection system should be set with a construction area of ≤ 500m2 cable dissection and electric basement; cable tunnel length ＞ 150m outside the main building of the regional cable tunnel (Gallery) road water spray, water mist system yishe master building, main electrical room important and fire risk large places of cable shaft water mist or other fixed fire extinguishing system yishe hydraulic station, lubricating oil station (library), rolling oil system, Central oil supply system, oil companies, the total volume of fuel tank tubing Gallery ≥ 2m3 underground hydraulic station and oil station (library), the total volume of oil should be more than an underground tubing Gallery 10m3 and oil-water mist and other fixed gas fire extinguishing system should be set floor elevation than 24m and tank total volume of high-altitude platform ≥ 2m3 closed hydraulic station; floor elevation 24m following, and the total volume of oil in the ground of ≥ 10m3 closed hydraulic station, lubricating oil station (libraries) should be located on the ground no station independent hydraulic station, lubricating oil system equipment and other technology facility or building water mist and other fixed gas fire extinguishing system is not set by table 1, for the cable tunnel, electrical basements, hydraulic station, lubrication station dangerous area, the fire extinguishing media can choose water fire suppression or extinguishing the fire, but with the current technological development in these regions, the basic gas fire-extinguishing system was eliminated and water fire extinguishing system development to high pressure water mist fire fighting system, shown in table 2 for water mist fire protection systems and fire-extinguishing systems performance comparison tables, as shown in table 3 for water mist systems performance comparison chart. Table 2 water mist CO2 inergen FM200 non-toxic is whether low cost is low and high generally do not harm the environment if it is a small footprint is significantly larger suction hyperpyrexia best poor poor poor people do not want to withdrawal in order to continue to use is not no space closed not strictly strict strict strictly through the awareness table 2 shows water mist system price/performance significantly better than other several gas fire extinguishing system, but also completely eliminates gas extinguishing system does not have many areas at the fire, environmental and system maintenance requirements. Table 3 high pressure water mist fog and low voltage fine water spray droplet diameter thin (≤ 200 μ m) thick (≤ 400 μ m) and coarse (≤ 10 μ m) spray intensity L/min.m21.3213 pipeline DN80 or so about requirements around DN150 DN250 8min12min24min spray less time consumption for many poor insulation performance is poor water affect the very small to larger very good flue gas dedusting General General cooling good general general store water in less than a lot of construction investment is moderate with moderate to low adoption awareness on table 3, known in the water mist systems, high pressure water mist and low pressure water mist, water spray compared also has great advantages. Water mist systems also have many area chain tracking technology and water fog isolation technology, a good solution to these regional fire has the potential to spread a fire. 5. fire sealing system design and analysis of fire-blocking belonging to passive fire protection system that is part of the building structure, is not easy to remove changes, relative to the active fire protection systems, they are interdependent, interrelated. When a fire occurs, passive fire protection system, although it is not possible to achieve the purpose of extinguishing fire immediately, but may prevent flames raged, protect the stability of the building structure, so that staff can be evacuated safely and firefighters to the scene of internal security. Evacuation evacuation basically have to rely on passive fire evacuation facilities, and fire safety devices as appropriate. Passive fire protection measures themselves unable to fire, only rely on active fire protection measures in order to implement the functionality of the fire-fighting the tobacco control and enables staff early fire information and intelligence, timely evacuation, at the same time protects the evacuation facilities. How to improve the overall safety performance architecture, the evacuation of a comprehensive selection of active fire protection measures and passive fire protection measures and to take full account of the needs of the building and the building fire safety performance, consider a variety of favourable and unfavourable external conditions. Cable fire sealing system as passive fire protection in a major fire protection measures in large fire protection system has been widely used. If the iron and steel works of substations, electric floor, power distribution unit, control room and cable tunnels of wires, cables, once the fire, will rapidlySpread of serious consequences. To guarantee the normal operation of equipment, wire, cable, fire protection design and construction should be safe, reliable and advanced technology. National fire regulations, mandatory requirement needed for the above regions implement cable fire sealing and fire resistance rating specification in order to prevent the spread of fire, accident prevention, will reduce fire losses to a minimum. 6. the summary as metallurgical enterprises cable tunnels, electrical basements, hydraulic station, lubrication station area a significant fire hazard, has always been a fire protection system protected object, through automatic fire alarm system, automatic fire extinguishing systems and fire-proof sealing system for reasonable, could reduce these parts of a fire caused by loss, the third set of system can be said to complement each other, are indispensable. References [1] the automatic fire alarm system design code (GB50116-1998) [2] the iron and steel metallurgy enterprises design fire protection standard law (approval) [3] DB33/1010-2002 "water mist fire protection system design, construction and acceptance (Zhejiang Province)