[China Aluminum Industry Net] Factors Affecting Explosive Materials The factors that affect the material of explosion suppression include raw material properties, structural dimension design, installation and design. Laminar Flow Type Air Sterilizer Home Sterilization,Sterilization Device,Medical Instrument Sterilizer,Laminar Flow Type Air Sterilizer Dongguan V1 Environmental Technology Co., Ltd. , https://www.v1airpurifier.com
Compared with copper, nickel, and stainless steel, aluminum has become a preferred material because of its low density, good thermal conductivity, high specific heat capacity, low price, and high recyclability. However, due to the corrosion of aluminum alloys by oils, their application has been hindered. For example, tanks and tanks used for transporting and storing aviation gasoline and kerosene have not dared to use 3003-H18 foil to suppress explosives, which means that they cannot be used by previous generations. Fire and explosion suppression materials, so the development of new explosion-proof materials, that is the second generation of fire suppression foil has become a top priority, the Chinese unit scientists have made gratifying achievements in this regard, the successful development of the performance of the second generation of fire explosion-proof aluminum alloy foil , ranking the international leading level.
The explosion-proof performance of the mesh-shaped aluminum alloy fireproof and anti-explosion product is related to its specific surface area, density, mesh number per unit volume and its size. In the manufacturing process, the smaller the draw ratio, the greater the density of the explosion suppression product, the larger the specific surface area, the larger the number of meshes, and the smaller the mesh size. When the size of the foil is constant, the flame retardant product draw ratio affects the flame propagation speed very significantly, and at a draw ratio of about 2.5, the flame propagation speed is small. Therefore, the explosive suppression effect can be controlled by controlling the stretching ratio during the manufacturing process of the explosion-proof product. In addition, the thickness of aluminum foil also has a certain impact on the explosive performance of the product: Under the same tensile ratio, the thicker the aluminum foil, the better the explosion suppression performance. The influence of the above factors and the quality of the materials should be taken into consideration in the design. At present, the thickness of aluminum foil used in the world is about 0.05mm, and there is a tendency to use thinner foils, especially in spherical anti-explosive products.
The structural tests at home and abroad show that the directivity of the explosion suppression product has no effect on its explosion suppression performance; the explosion suppression pressure increases with the increase of the container blanking rate, and decreases with the increase in the density of the mesh aluminum alloy explosion suppression material, and Each blanking rate has a relatively better value for the density of the suppression material.
The operating factors in the work of the mesh aluminum alloy explosion suppression product may undergo compression deformation, generate a cavity, and then affect its anti-explosive performance. Tests have shown that the deformation in the vertical direction is small and the resulting elastic deformation is less than 5%, while the load that can withstand is much greater than the bearing capacity when used; materials in other two directions may be generated under long-term or stress conditions. Longer deformation, but under normal working load conditions, the deformation will not exceed 5%.
Effects of Forming and Flight Vibration on Mechanical Properties of Anti-explosive Aluminum Foil Since the beginning of the new century, reticulated anti-explosive aluminum foil has been used in aircraft fuel tanks. The scientists' simulated flight vibration experiments have no effect on the fracture characteristics of anti-explosive aluminum foil. The tensile strength Rm of the vibration sample and the original sample is 58.8N/mm2~205.8Nmm2, and the dispersion is severe. This is because the explosion-proof net is impacted, cut, and bent into a net shape during the forming process, and the stress deformation degree of various parts. Non-uniformity, resulting in non-uniform thickness, resulting in non-uniform mechanical properties. At the same time, aluminum foils have undergone different cold hardening in the process, so that the average tensile strength increases significantly. This shows that the work hardening has a significant impact on the tensile strength of the explosion-proof aluminum foil, but the simulated vibration experiment does not reduce the mechanical properties of aluminum foil mesh materials.
The application of anti-explosive aluminum foil to the net or balls of the 3003 alloy foil made of anti-explosion foil to store flammable and explosive gas and liquid containers can effectively prevent the explosion of fire. Even in the event of a fire, the explosion can be suppressed and the loss can be reduced. Lowered to a low value, to gain valuable time for firefighting. When the oil tank is damaged, it can be directly repaired with oil, gas welding or gas welding without draining the oil.
This aluminum foil explosion suppression product has been widely used in foreign industrial and commercial gasoline tanks. The fuel tanks for buses, trucks, bulletproof limousines, oil tankers, special police vehicles, fire engines, and armored cars, and the outer tanks of helicopters are all equipped with Aluminum foil detonation net or ball. Anti-explosive materials can be applied to storage containers of flammable and explosive products such as gasoline, alcohol, thinner, acetone, ether, coal gas, acetylene, liquefied petroleum gas, and liquefied natural gas to prevent explosions in accidents. Domestic military vehicle fuel tanks are being tested. With people's increasing emphasis on safety issues, explosion-proof products will be widely used in the storage and transportation of oil, flammable and explosive chemical products.
During the Gulf War, 3003 alloy foil detonation nets were installed in the fuel tanks of American helicopters and tanks. In April 2005, the State Administration of Work Safety approved the “Technical Requirements for Obstruction and Anti-explosion Storage Tanks for Automobile Refueling (Gas) Stations, Light Fuel Oil, and Liquefied Petroleum Gas Tank Vehicles (AQ3001-2005)†as a mandatory safety production industry standard. It will further promote the development of barrier suppression technology and the development of explosion-proof materials.
After the explosion-proof materials are filled in aircraft and helicopter fuel tanks, they will not explode even if fired. Aluminum alloy suppression materials have also been applied to surface ships. The light attack patrol ship 462L produced by Ramo Inc. (RAMO) in the United States has been subjected to the use of 300-gauge light-explosive and armor-piercing firebombs. No explosion occurred in the test.
In the comparative experiment, the Defence Research Board of Canada adopted six liquefied petroleum gas cylinders with a one-fifth reduction ratio. The tanks were made of 6mm steel plates and had a volume of 947L. Four of them were filled with mesh aluminum foil explosion suppression products. The tank is filled with 85% liquefied petroleum gas and burned with Jp-4 kerosene to reach 1094°C. Two tanks without anti-explosion products explode within 8 minutes, while the other four tanks equipped with anti-explosion aluminum foil are inside. The liquefied petroleum gas did not explode when it dried.
Brivex (Blvex) has applied a special bubbling coating on the surface of the explosion-proof aluminum foil. When heated above 120 °C, the paint can form a highly efficient carbon-based heat insulation layer. This is called " The "firewall" material is wrapped outside the protected container and can directly limit the amount of heat entering the container. The Health and Safety Executive conducted tests with a 400-liter liquefied petroleum gas tank: the tank was exposed to a propane propane cabinet with an output heat of 4.5 MW. After being held for 25 minutes, the tank was covered with a "fire wall". At a pressure of 900 N/mm2, the higher temperature of the liquid is only 17° C., and the pressure inside the container after heating for 3 min without coating the “fire wall†paint is as high as 2758 N/mm 2 .
The market potential is great The second-generation anti-explosive foil project should be constructed. The aluminum alloy fire-prevention explosion foil is a material with a huge market potential. It is used in containers of oil products and other inflammable and explosive dangerous goods during transportation, storage and use. Filling this kind of material can effectively prevent and suppress combustion and explosion. It has been widely used in foreign countries and has also been applied in certain special sectors, playing a significant role in protecting the safety of life and property. The loading amounts to 1% of the container volume to 2% of the container volume. This type of explosion suppression product has a net shape and a spherical shape. The net shape product can be pre-loaded during the manufacture of medium and small containers, and can be loaded at any time for large containers such as oil tanks in use.
China is a big country for energy production and consumption. The transportation, storage, and use of flammable and explosive dangerous goods are very large. If each container is loaded with explosion-proof products, the oil products, liquefied petroleum gas, and oil products consumed in 2015 will be retained. Estimates for transport vehicles, storage tanks, and liquefied gas cylinders (loading volume at 1.5% container volume) require suppression of the product by approximately 900 kt. At present, the blast suppression products are made of 0.05mm thick 3003-H18 or -H28 alloy foil. This is a conventional foil. The production process is complicated and the processing cost is not high, but unfortunately, this kind of suppression is based on the previous generation. The anti-explosive products made of aluminum foil can not be reused because they are soaked for about 1 year in flammable and explosive dangerous goods such as oil and liquefied gas and must be replaced. Therefore, research and development and production of long-lived second-generation fire and explosion suppression materials that are not subject to corrosion by oil, liquefied gas, etc. are imperative. They are the shortcomings of China's aluminum industry and need to be filled.
China has developed a second-generation fire-retardant anti-explosion aluminum alloy with intellectual property. Through the foregoing introduction, we know that the previous generation of fire and explosion suppression products were made of 3003-H18 alloy foil. The research and application at home and abroad have proved its mechanics. Performance can meet the requirements, but the service life is only 1a, far from meeting the demand. Therefore, an aluminum alloy with higher corrosion resistance should be sought. From common sense and theoretical analysis, it can be known that the fire-extinguishing and anti-explosion aluminum alloy must have high mechanical properties and strong resistance to oil corrosion, and the corrosion resistance of the 3xxx-based alloy to the oil is insufficient, then the 1xxx, 4xxx, and 8xxx alloys are The service life of oil and liquefied gas is not much longer, and their mechanical strength is not enough to counter automobile bumps and aircraft vibrations. Although 2xxx and 7xxx series alloys have high strength properties, their corrosion resistance is very low. The second-generation fire suppression aluminum alloy can only be found in the 5xxx and 6xxx alloys. Through many years of research and development, professors from a material department of a well-known university in China have developed fire-retardant anti-explosive aluminum foil alloys with all intellectual property rights. Laboratory tests and road tests have proved that its service life is much longer than that of 3003-H18 alloy foil, and it is the world's first. . Although its composition has not been announced yet, it is not a 5xxx series alloy or a 6xxx series alloy, and sooner or later it will be widely known for the widely used civil alloy composition.
It is imperative to build a second-generation fire-fighting and anti-explosive aluminum foil factory with a production capacity of 50kt/a. With the second-generation fire-retardant foil aluminum alloy, the next step is to build an industrialized aluminum foil plant, which is specialized in producing fireproof and anti-explosive foils. It can cooperate with universities that have such foil intellectual property rights, build a joint venture, produce talents from schools, invest funds from investors, and manage factories. Build a production capacity of 50kt/a and professionally produce 0.05mm thick, and use a professional foil rolling mill to roll 3 passes to make 0.28mm blank strip reach 0.05mm foil. The main equipment (excluding the casting workshop): 1 1650mm 4 reversible hot rolling mill, 2 1500mm 5 irreversible cold rolling mills, 6 1500mm 4 irreversible large rolling force foil mills, 30 annealing furnaces, slitting There are 3 aircrafts, other auxiliary equipment, and some automated process parameter controls that need to be imported together. However, the number is small and the cost is not large. According to calculations, the investment in fixed assets such as equipment is about 280 million yuan.
It is also necessary to develop thermal insulation coatings on external surfaces of bottles and cans to apply these coatings to the surface of bottles and cans containing flammable and explosive substances. The insulation properties of the cans should be strong to prevent external heat from being transferred to the cans and to prevent internal pressure from rising. Few or high rises will not explode. This combination of external thermal barriers and internal explosion suppression products ensures safety and security.
R&D and construction of second-generation anti-explosion aluminum foil project