Combustion performance and countermeasures for building thermal insulation materials Before Xu Xiu, Daqing City Public Security Fire Brigade, Daqing 166500, Heilongjiang Province, a fire broke out in the new CCTV building in 2009, and the building's external thermal insulation materials were pushed to the trial stage of public opinion as a “helperâ€. The fire is ruthless, and under the heavy sacrifice of life, the wall insulation material cannot fail to face the most stringent safety test in its development history. In this paper, the combustion performance of building exterior wall insulation materials is analyzed, and related solutions are proposed to eliminate the safety hazards of exterior wall insulation materials.
On September 25, 2009, China formulated the temporary regulations for the fire protection of civil building exterior insulation systems and exterior walls: the height of non-curtain wall residential buildings is greater than or equal to 100m, and the combustion performance of insulation materials should be Class A; the height is greater than or equal to 60m and less than 100m. The combustion performance of the insulation material should not be lower than the B2 level. Therefore, how to eliminate the safety hazards of exterior wall insulation materials, whether to further improve the fire protection level of insulation materials and external insulation systems, has become a problem that construction industry experts and scholars have been thinking about, and has become a livelihood issue that the government must pay attention to and urgently need to solve.
1 Analysis of the combustion performance of building exterior wall insulation materials 1) The market for building exterior wall insulation materials is chaotic. The entry barriers for China's building materials market are relatively low, the relevant technical standards and management regulations are still not perfect, the management level is not high, and the enterprise self-discipline is not enough. Therefore, the material of the insulation material market is shoddy and the quality is inferior, and the related data fraud will also be popular. The market chaos will bring disaster to the benign development of the insulation material itself, which is not conducive to the improvement of the comprehensive performance of the insulation material and the upgrading of the product. The impact on the whole industry will be It is negative. 2) Analysis of combustion performance grades and types of common insulation materials: (1) Analysis of combustion performance. According to GB8624-2006 building materials and products burning performance classification, and GB50222-95 building interior design fire protection specifications, materials are divided into four grades according to combustion performance: A grade is non-combustible material, and B1 grade is flame retardant material. To reach the B2 level is a combustible material. Inorganic materials are used to achieve Class A combustion performance. Insulation materials are aimed at reducing heat loss. Under normal circumstances, materials with thermal conductivity below 0.05W/mk, thermal conductivity should be less than 0.14W/mk, which is called high-efficiency insulation material; (2) analysis of combustion performance. First, the type of insulation material for Class A. Foam glass, rock (mineral) cotton, inorganic thermal insulation mortar, etc. Secondly, the thermal insulation materials with B1 grade combustion properties include phenolic and rubber powder polystyrene particles. Insulation materials with B2 grade insulation properties include: polyurethane (PU), molded polystyrene board (EPS), polyethylene (PE) extruded polystyrene board (XPS), and the like.
Third, the insulation material of the fire barrier can be made of materials such as foam glass, rock (mineral) cotton, inorganic thermal insulation mortar and the like. Fourth, the external thermal insulation system and external wall decoration fire protection design must comply with the relevant provisions of the current national standards and standards. The combustion performance of the external thermal insulation materials used should be Class A. The external thermal insulation system of the wall should be made of non-combustible or non-combustible materials. The fire resistance of the protective layer and the wall shall comply with the fire protection code. 3) Performance analysis of inorganic insulation materials. First, mineral wool analysis. Mineral wool is made of molten metallurgical slag by flocculation or centrifugation. It has the characteristics of sound absorption, heat insulation and non-combustion. The weight of mineral wool board used in design is 80kg/m3~160kg/m3, thermal conductivity: 0.044W/mk due to the low acidity coefficient of mineral wool, the physical properties are unstable compared with rock wool, and it contains more alkaline oxides, so it is incombustible material, grade A. Second, glass wool. The molten glass is fiberized to form a fluffy cotton-like material. In the design, some organic components are added in the production process, and it is a non-combustible material, grade A. 4) Performance analysis of inorganic insulation materials. First, extruded polystyrene foam board (XPS). A foamed plastic having a closed cell structure by heating and extruding a polystyrene resin as a main material. It is generally considered that the XPS board is a combustible material, B2 grade, the weight of the EPS board commonly used in the design: 25kg/m3~32kg/m3, the thermal conductivity: <0.03W/mk, and the polystyrene foam board (EPS). After the pre-expansion of the polystyrene resin particles by heating, a foam having a closed cell structure and having a use temperature of not higher than 75 degrees is formed in the mold. The EPS board in the design is a combustible material, grade B2.
2 Combustion solutions for building exterior insulation materials 1) Selection of fireproof materials. First of all, the protective layer of the external wall of the building should be completely covered by the thermal insulation material, and the thickness of the protective layer of the first layer should not be less than 6mm, and the other layers should not be less than 3mm. At the same time, the decorative layer of the external wall should be made of non-combustible material. When the exterior wall of the building is made of combustible insulation materials, it is not advisable to use materials such as tiles that are easy to fall off after the fire. Secondly, when it is necessary to install a fireproof insulation belt, a Class A insulation material with a width of not less than 300 mm should be set along the floor. For metal sandwich composite panels used in temporary residential buildings, the core material should be non-combustible or non-flammable insulation materials. Third, the use of non-transparent curtain wall structures such as stone and metal must be provided with a base wall. The fire resistance limit should comply with the relevant provisions of the current fire code on the fire endurance of the outer wall. The refractory limit and fireproof construction of the window sill wall and skirt wall of the glass curtain wall shall comply with the relevant provisions of the current fire protection regulations for building curtain walls. At the same time, the space between the internal cavity of the base wall and the building curtain wall and the base wall, the window partition wall, the window sill wall and the skirt wall shall be sealed with fireproof sealing material at each floor slab; 2) Insulation material Fire protection technology used in construction. First of all, the fire protection requirements for the construction of the external insulation system. After the insulation material enters the site, it must be kept away from fire. The shafts, grooves, platforms, etc. adjacent to the external wall and the roof should not be stacked with combustibles. If it is to be stored in the open air, it should be completely covered with non-combustible materials. At the same time, for the construction of flammable and explosive, the construction of flame retardant insulation materials shall be carried out in sections, and each section shall maintain sufficient fireproof spacing, and it is advisable to apply a protective layer while fixing the insulation material, and for the external insulation material without applying the protective layer. The height should not exceed 4 layers. Fire hazards such as fire sources and heat sources should maintain a certain safety distance from the roof and external walls, and should be strengthened. Secondly, the supporting members of the curtain wall and the supporting members of the air conditioner and other facilities shall be subjected to electric welding and other processes before the insulation material is laid. If it is necessary to carry out the insulation material after laying, the fire blanket shall be laid around the bottom and the bottom of the electric welding part. Fire protection measures. Third, the external thermal insulation material that needs to adopt fireproof construction measures shall be constructed in parallel with the construction of the thermal insulation material.
Hot melt construction of waterproof materials shall not be carried out directly on flammable insulation materials. At the same time, it is not advisable to carry out drilling and welding work on walls and roofs with external thermal insulation materials. If construction work is required, reliable fire protection measures shall be taken, and the exposed external thermal insulation materials shall be treated in a timely manner after the completion of construction.
In short, with the advancement of science and the development of technology, many buildings have adopted a large number of exterior insulation decoration and decoration materials in order to pursue novel appearance or due to technical requirements.
However, some of these external thermal insulation and exterior wall decoration materials use flammable materials, which are highly prone to fires, causing heavy casualties and huge economic losses. Therefore, the building exterior insulation system and the exterior wall decoration fire protection should be taken seriously.
(Finish)
The battery is used in the situations for power requirements with high and low temperature performance, high energy density, such as tire pressure monitor system(TPMS), car keys, industrial control board,computer motherboard, intelligent instrument, unattended operation instrument and other applications.
Button Lithium-fluorocarbon Battery (Li-(CFx)n) Models Of BR1025
Shandong Zhongshan Photoelectric Materials Co., Ltd , https://www.chzsem.com