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Steel plant span characteristics and fire fighting measures

    With the rapid development of China's economic construction, production and storage space become large, steel frame construction of the plant, to high strength, light weight, large span, lifting to facilitate the construction and construction time is short and so is increasingly the majority of used by manufacturers.
    But the large span in use, but also to the fire has caused a new subject, in the event of fire, the steel heat faster,booster cables these large steel plant can easily collapse. In recent years, China has more than steel plant fire occurred, the state property caused a greater loss. In particular, we are familiar with the collapse of the New York World Trade burn is a typical steel structure fire. Here features a large steel plant fire fighting measures and talk about some plain view.

    First,battery clip the characteristics of steel in the fire.

    Poor fire resistance of steel, heated, soon the plastic changes in the fire for 15 minutes or so, members would like a "noodle" soft as down, with the partial destruction and damage caused by the overall loss of stability. For the destruction of the steel is very difficult to repair. We used in the construction of steel,tow rope high strength at room temperature, but when the temperature rose to 500 degrees, the strength of steel began to gradually lose its strength and has only half the normal value, loss of support capacity. According to survey construction commonly used in cold rolling steel, fire-resistant properties of its failure temperature of 538 degrees, ratchet tie dowm and general fire, when fire for 5 minutes, the temperature reached 556 degrees. Therefore, the theory of general fire resistance of bare steel is only about 15 minutes.

    Second, the steel plant fire characteristics.

    (A) the fire heating up fast, fast weakening of steel components, easy to collapse. Steel at room temperature, non-burning materials, but steel's thermal conductivity is 40 times that of concrete and steel components as a single material, so the temperature in the fire fast.

    (B) a large space, the fire spread quickly. Large steel plant covers an area of large, generally greater than 7 meters in height, has a larger interior space, good air circulation. The production and use of raw materials and finished products are mostly combustible; and in extensive use in the production of electrical equipment and multi-channel processing procedures, the event of fire, the fire can spread in any direction, burning fiercely, easy to produce strong thermal air currents to form a large area combustion.

    (C) of the equipment, personnel-intensive, large fire load, evacuation difficulties. Large steel plant scale, structural piece into a film, production machinery and equipment-intensive, high concentration of people and goods, a large fire load, evacuation means less; case of fire smoke large, because of the long-term workers to work from a fixed line, vulnerable to fire when the increasingly tense and the formation of public behavior, is not conducive to escape evacuation, can easily result in Qunsiqunshang.

    Third, fighting measures.

    (A) establishing a "cooling before the fire," the dominant position.

    Steel frame factory in the event of fire, steel columns carrying capacity will be lost in a short time, distortion, collapse phenomena, not only that could lead to heavy casualties, but also make the building collapse and damage of property due to ; the same time, after the collapse of well-ventilated combustion, will further accelerate the fire spread, a relatively short time a large area of fire; In addition, the collapse of a large number of steel members piled on the pressure in the combustion products, but also to bring more fighting difficult. Thus, in fire fighting, only focus on the overall structure of the building to ensure the safety of fire fighting was losing significance and role. To do this, the cooling of steel members as soon as possible is the only effective way. This temperature change in the fire or the ambient temperature enhancement, so that its humidity falling steel components, thus effectively ensuring the strength of steel components are not destroyed. Meanwhile, the cooling of water vapor emitted by the steel can increase the humidity of the fire, reducing fire, the ambient temperature. If under the conditions of 100 ℃, one kilogram of water into steam to absorb the heat 539 kcal. Meanwhile, the water into steam, its volume expands 1725 times, water vapor combustion zone occupied space, not only increased the temperature, but also creates conditions of the gas cut off from the air, to suffocate the fire or impede the spread of fire-fighting role.
    In addition, the cooling water flow can be reflected directly off the fire. Therefore, with enough water cooling of steel structures, has great advantages, cooling should be on fire, should be the first principle of fighting fire steel, but the implementation of the cooling and fire can not be separated between the two. The fire will be different, which calls for fire and fire-fighting commanders based on the balance of power, a good combination of the two, depending on the situation, deal with the relationship between the cooling and fire suppression. That the suppression of steel deformation, under the premise of preventing the collapse of buildings for fire fighting, when the fire power is sufficient, cooling and fire could be conducted, for the construction and other combustible components and internal materials, equipment and starts, to synchronize the deployment force, for cooling and fire-fighting, lack of strength, should be the threat of building elements to control the fire.
    (B) the fire detection as a necessary condition for winning fire.

    Fire fighting in the steel plant, the fire in a large space, the fire burned the main highlight, the situation is complex and difficult to increase the fire fighting. Therefore, fire detection timeliness, accuracy and continuity of fire fighting safety and security is a prerequisite for the correct implementation of which requires us to fire reconnaissance. In the course of fire, to ensure the accuracy of detection, continuity. Surveillance process, found that commanders in time to report dangerous situations, too late to report, to be drastic measures. Technical reconnaissance operations personnel can use thermometer, always grasp the temperature of the fire, the use of bolometer thermal radiation intensity measured at any time and the fire temperature, for determining the fire tactics, fire techniques, tactical operations and provide a reliable theoretical basis. Meanwhile, the commander should be arranged as experienced fire inspector, on the combustion characteristics of the building sustained, comprehensive observation, development and changes in the understanding of the fire at the same time, and pay attention to the fire floor load bearing building elements, object deformation, surface crack, crack, break the sound and so on. Through the burning time, area, fire, temperature and component deformation analysis of the situation Chengdu, changes in the structure of the building to observe the surrounding fire conditions, to determine the possibility of building collapse, the threat of the spread of fire and the need for evacuation.

    (Iii) reasonable ripper means for changing an effective means of fire spread.

    Spread of the fire to a large extent dependent on the fires spread of high-temperature flue gas, flue gas flow rate and gas diffusion temperature on the flow direction. Large floor area of a large frame structure, but the scope of the fire is often the initial fire is limited. Can not be blind in fire fighting ripper windows and doors, the principles of fluid mechanics to the implementation of rational use of scientific ripper, ripper position once the improper expansion will make the fire quickly spread to the entire space. In the heat inside the building filled with smoke and the case of windows and doors can only be implemented on the windward side of the ripper to minimize the entry of fresh air and delayed the development of the fire, while shooting the water through the gun lower the temperature. If both operated rescue on the doors and windows under the wind, the fire quickly spread along the gas to expand. If the roof has skylights, fire resistance in the components within the time frame in ensuring safe conditions ripper burning point above the roof, so that smoke and heat from the top of the exported product. Meanwhile, the roof and the ground staff to keep in touch with the offensive staff, roof ripper synchronized with the ground cover for the implementation of the cooling water gun. But when the fire burning longer than the time limit when the element fire, the roof ripper undesirable.

    (D) a reasonable choice fighting positions, the proper use of fire fighting equipment is an essential element to tackle tough.

    Steel fire fighting fire with brick and wood are different, we should give full play to the advantage of modern equipment to make use of long range and large caliber gun, mobile artillery, guns and other vehicle, from a distance to the roof, windows, water cooling and extinguishing fire on multi-directional cooling buildings, to prevent building collapse wounding. The layout position of the gun, the officers and soldiers can not fire blindly into the house to save, organize elite forces to try to minimize the climb and the number of personnel into the interior of the fire, fire stop place a safe distance. Should be arranged in the external water gun positions, long-distance shot of water cooling, the temperature dropped in the fire within the safety factor, after repeated reconnaissance to confirm elimination of danger of collapse, and rapidly adjust the gun positions, can rely on doors, windows and other parts of set water gun positions, from different perspective to enhance fire storm, with a strong jet near the fire point-intensive fire.
    In combat operations, to take to become more fire-fighting tactics, and for large span steel plant area, multi-fuel combustion characteristics of a violent, it is timely to open up more offensive channels, concentrating a superior force, in particular the need ripper building layout gun positions or evacuation of persons and goods should be flexibility in the use rescue tools on the plant's fence, rolling gates, windows and other implementation ripper, provide access for fire fighting to save people form a more offensive to surround and annihilate the purpose to prevent the fire temperature increased, to avoid the risk of collapse. Furthermore, the use of high-power water guns, water cannons, the operator should try to pay attention to the transformation flow to minimize water loss, cooling should be uniform on a comprehensive building components to prevent excessive water in the formation of a larger local impact, Local sudden drop in temperature caused by, causing shrinkage of building components.

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iande Weida Electrical Appliance Tools Co.Ltd. professionally manufacture booster cables , battery clip, tow rope,ratchet tie down.