15mm tempered glass
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19mm tempered glass help editor encyclopedia card tempered glass 19mm tempered glass: belongs to safety glass. Tempered glass is actually a kind of prestressed glass. In order to improve the strength of glass, chemical or physical methods are usually used to form compressive stress on the surface of glass. When the glass bears external forces, it first offsets the surface stress, thus improving the bearing capacity, and enhancing the resistance to wind pressure, cold and heat, impact, etc. of the glass itself. Features and Advantages 19mm tempered glass is super thick glass, which is the later building material glass used in buildings at present. Due to its special properties, such as safety, light transmission, glass printing and baking paint, 19mm tempered glass is favored by many developers. 19mm tempered glass is not only safe but also beautiful for building decoration, Therefore, most buyers also prefer 19mm tempered glass. Strength: Compared with ordinary glass, tempered glass can improve the strength and bending resistance several times. The impact strength of tempered glass with the same thickness is 3-5 times that of ordinary glass, and the bending strength is 3-5 times that of ordinary glass. Safety: The increase of its bearing capacity improves its fragile property. Even if the 19mm tempered glass is broken, it will appear as small pieces without acute angles, which will greatly reduce the harm to human body. The tempered glass's resistance to rapid cooling and rapid heating is 2-3 times higher than that of ordinary glass, and it can generally withstand the temperature difference of more than 150LC, It has obvious effect on preventing thermal cracking. The thermal stability tempered glass has good thermal stability. It can withstand a temperature difference of 3 times that of ordinary glass and a temperature difference of 200 ℃. Usage: Flat tempered glass and bent tempered glass belong to safety glass. Widely used in high-rise building doors and windows, glass curtain walls, indoor partition glass, daylighting ceiling, sightseeing elevator channels, furniture, glass barriers, etc. Standard specification ① Flat tempered glass processing specification: processing thickness: 19mm; larger size: 3300mm × 16000mm (only Henan Fuxin Glass Co., Ltd. can complete the processing of this page in China); smaller size: 300mm × 300mm; quality: in accordance with the Chinese national standard GB15763.2-2005. Disadvantages of tempered glass: 1. The tempered 19mm thick glass can not be cut and processed, but can only be processed to the required shape before tempering, and then tempered. 2 Although the strength of tempered glass is stronger than that of ordinary glass, tempered glass has the possibility of self explosion (self rupture) when the temperature difference changes greatly, while ordinary glass has no possibility of self explosion. The transportation of 319mm tempered glass is a bottleneck for glass deep processing enterprises. 19mm tempered glass is mostly large-sized glass, and the wider 19mm tempered glass is either super high or super wide whether transported vertically or horizontally. The production process of 19mm tempered glass belongs to super thick glass. The processing size is relatively large, and the size of the tempering furnace is also very large. The furnace body is relatively rough, and the flatness of the glass is relatively high. This is why the surface of the glass is uneven. The severity depends on the quality of the equipment. This is also why the tempered glass cannot be used as a mirror. Emergency method safety hammer: an auxiliary escape tool in a closed cabin. It is generally installed in an easily accessible place in an enclosed compartment such as a car. In case of an emergency such as a fire in the car or a car falling into the water, it can be easily taken out and smashed the glass window door for smooth escape. Usage: It is mainly used to break the glass to escape in an emergency. The hammer is used to hit the rear blade of the glass handle to cut the safety belt for escape. Scope: mainly used for bus, passenger vehicle, train and other vehicle configurations. How to use: The safety hammer mainly uses its conical tip. Because the contact area of the tip is very small, when the hammer is used to hit the glass, the pressure of the contact point on the glass (not the pressure, but the pressure on the unit area) is quite large. This is a bit similar to the principle of thumbtacks, and the membrane is easily punctured, In addition, the car glass is subject to a large external force at this point, resulting in a slight crack. For tempered glass, a little crack means that the stress distribution inside the whole glass has been damaged, thus generating numerous spider web cracks in an instant. At this time, only a few more blows with a hammer can remove the glass fragments. In addition, the middle part of tempered glass is firm, and the four corners and edges are weak. It is better to use a safety hammer to hit the edges and corners of the glass, especially the middle part of the upper edge of the glass. Once the glass has cracks, it is easy to break the whole glass. In general, the sharp knife like sharp corner of common glass in building formwork is easy to cut children or strikers, causing personal injury. The main difference between tempered glass and ordinary glass is whether the glass is broken into small particles or knife shaped. But in engineering inspection, it is no doubt unrealistic to adopt such destructive inspection. How can you know whether you bought tempered glass or not? This also has to be analyzed from the manufacturing principle of tempered glass. Tempered glass is obtained by cutting ordinary annealed glass into the required size, heating it to the near softening point, and then cooling it quickly and evenly. After tempering, uniform compressive stress is formed on the surface of the glass, while tensile stress is formed inside, which greatly improves the performance of the glass. The tensile strength is more than 3 times of the latter, and the impact resistance is more than 5 times of the latter. It is also this feature that the stress feature has become an important symbol to identify the true and false tempered glass, that is, the tempered glass can see color stripes at the edge of the glass through the polarized light sheet, and black and white spots can be seen on the surface layer of the glass. The polarizing lens can be found in the camera lens or glasses. When observing, pay attention to the adjustment of the light source, so that it is easier to observe. Each tempered glass has a 3c quality safety certification mark Self explosion defect The automatic explosion of tempered glass without direct mechanical external force is called self explosion of tempered glass. Self explosion is one of the inherent characteristics of tempered glass. There are many reasons for self explosion, which can be simply summarized as follows: ① The influence of glass quality defects A. There are stones and impurities in the glass: impurities in the glass are the weak point of tempered glass, and also the stress concentration point. In particular, if the stone is located in the tensile stress zone of tempered glass, it is an important factor leading to cracking. Stone exists in glass and has different expansion coefficient from that of vitreous body. After glass tempering, the stress concentration in the crack area around the stone increases exponentially. When the expansion coefficient of stone is less than that of glass, the tangential stress around the stone is in tension. Crack propagation associated with stones is very easy to occur. B. The glass contains nickel sulfide crystals, nickel sulfide inclusions generally exist as small crystalline spheres, with a diameter of 0.1-2 mm. The appearance is metallic. These impurities are NI3S2, NI7S6 and NI-XS, where X=0-0.07. Only NI1-XS phase is the main reason for spontaneous explosion of tempered glass. The known theoretical NIS is 379. There is a phase transformation process at C, and the volume expansion of 2.38% is accompanied by the transformation from the a-NIS hexagonal system at high temperature to the B-NI trigonal system at low temperature. This structure is preserved at room temperature. If the glass is heated later, the a-B state transition may occur rapidly. If these sundries are inside the tempered glass under tensile stress, the volume expansion will cause spontaneous cracking. If a-NIS exists at room temperature, it will also slowly change to B state after several years and months. In this phase transition process, the slow increase in volume may not cause internal fracture. C. The glass surface is prone to stress concentration or self explosion of tempered glass due to scratch, crater, deep edge and other defects caused by improper processing or operation. ② The stress distribution in tempered glass is uneven, and the temperature gradient generated along the glass thickness direction when the offset glass is heated or cooled is uneven and asymmetric. It makes the tempered products have a tendency of self explosion, and some produce "wind explosion" when chilling. If the tensile stress zone shifts to one side of the product or to the surface, the tempered glass will explode spontaneously. ③ The experiment shows that the number of spontaneous explosions reaches 20-25% when the degree of tempering is increased to level 1/cm. It can be seen that the greater the stress, the higher the degree of tempering, and the greater the spontaneous explosion amount. Solution to self explosion of tempered glass 1. Reduce the stress value of tempered glass. The distribution of stress in tempered glass is that the two surfaces of tempered glass are compressive stress, the core layer of the plate is in tensile stress, and the stress distribution in the thickness of glass is similar to a parabola. The center of the glass thickness is the vertex of the parabola, that is, where the tensile stress is high; The compressive stress is near the two surfaces of the glass on both sides; The zero stress surface is located at about 1/3 of the thickness. By analyzing the physical process of tempered quenching, it can be seen that there is a rough proportional relationship between the surface tension of tempered glass and the larger tensile stress inside in numerical value, that is, the tensile stress is 1/2~1/3 of the compressive stress. Domestic manufacturers generally set the surface tension of tempered glass at about 100MPa, and the actual situation may be higher. The tensile stress of tempered glass itself is about 32MPa~46MPa, and the tensile strength of glass is 59MPa~62MPa. As long as the tension generated by nickel sulfide expansion is 30MPa, it is enough to cause self explosion. If the surface stress is reduced, the tensile stress of the tempered glass itself will be reduced accordingly, thus helping to reduce the occurrence of spontaneous explosion. The surface stress range of tempered glass specified in American standard ASTMC1048 is greater than 69MPa; The semi tempered (heat strengthened) glass is 24MPa~52MPa. The curtain wall glass standard BG17841 specifies a semi tempered stress range of 242. Make the stress of the glass uniform and uniform. The uneven stress of the tempered glass will significantly increase the spontaneous explosion rate, which has reached a level that cannot be ignored. The self explosion caused by uneven stress is sometimes very concentrated, especially the self explosion rate of a specific batch of bent tempered glass will reach an alarming degree, and may occur continuously. The main reasons are the uneven local stress and the deviation of the tension layer in the thickness direction, and the quality of the original glass sheet itself has a certain impact. Uneven stress will significantly reduce the strength of the glass, which is equivalent to increasing the internal tensile stress to a certain extent, thus increasing the spontaneous explosion rate. If the stress of tempered glass can be evenly distributed, the spontaneous explosion rate can be effectively reduced. 3. Interpretation of hot dip treatment (HST). Hot dip treatment is also called homogenization treatment, commonly known as "detonation". Hot dip treatment is to heat the tempered glass to 290 ℃± 10 ℃ and keep it warm for a certain period of time, so as to promote nickel sulfide to rapidly complete the crystal phase transformation in the tempered glass, so that the tempered glass that could explode after use can be artificially broken in the factory's hot dip furnace in advance, thus reducing the self explosion of tempered glass in use after installation. This method generally uses hot air as the heating medium, which is called "Heat Soak Test" (HST) in foreign countries. Hot dip difficulties. In principle, hot dip treatment is neither complicated nor difficult. In fact, it is not easy to reach this process index. The research shows that there are many specific chemical structure formulas of nickel sulfide in the glass, such as Ni7S6, NiS, NiS1.01, etc., not only the proportion of various components is different, but also other elements may be doped. The speed of its phase transition is highly dependent on the temperature. The research shows that the phase transformation rate at 280 ℃ is 100 times that at 250 ℃, so it is necessary to ensure that all glass in the furnace experience the same temperature regime. Otherwise, on the one hand, due to insufficient heat preservation time for glass with low temperature, nickel sulfide cannot completely transform, which weakens the effect of hot dip. On the other hand, when the glass temperature is too high, it will even cause the reverse phase transformation of nickel sulfide, causing greater hidden danger. Both of these situations will lead to ineffective or even counterproductive hot dip treatment. The uniformity of temperature during the operation of hot-dip furnaces is so important. Three years ago, the temperature difference in most domestic hot-dip furnaces even reached 60 ℃ when they were hot-dip holding. It is not uncommon for imported furnaces to have a temperature difference of about 30 ℃. Therefore, although some tempered glass has been heat soaked, the self explosion rate is still high. The new standard will be more effective. In fact, the hot dip process and equipment have also been constantly improving. The insulation time specified in German standard DIN18516 (Edition 90) is 8 hours, while prEN14179-1:2001 (E) standard reduces the insulation time to 2 hours. Under the new standard, the effect of hot dip process is very significant, and there are clear statistical technical indicators: after hot dip, it can be reduced to one case of spontaneous explosion per 400 tons of glass. On the other hand, the design and structure of the hot-dip furnace are constantly improved, and the heating uniformity has also been significantly improved, which can basically meet the requirements of the hot-dip process. For example, the self explosion rate of the hot dipped glass of CSG has reached the technical indicators of the new European standards, and has performed extremely satisfactorily in the 120000 square meter Guangzhou New Airport Mega project. Although the hot dip treatment can not guarantee that there will be no spontaneous explosion, it does reduce the occurrence of spontaneous explosion and solve the problem of spontaneous explosion that puzzles all parties in the project. Therefore, hot dip is an effective method to completely solve the problem of self explosion, which is unanimously recognized in the world. The purpose of studying the self explosion of tempered glass is to find a better solution. The purpose of comparing the effect and reliability of different solutions is to further reduce the spontaneous explosion rate and reduce the loss caused by spontaneous explosion. Based on the above analysis and comparison and the actual situation of engineering glass, several suggestions are proposed for reference only. Precautions The products shall be packed in containers or wooden cases. Each piece of glass shall be packed with plastic bags or paper, and the space between the glass and the packing box shall be filled with light and soft materials that are not easy to cause appearance defects such as glass scratches. The specific requirements shall comply with relevant national standards. Packing marks Packing marks shall comply with the provisions of relevant national standards, and each packing box shall be marked with words such as "upward, light handling and upright, careful breaking, glass thickness, grade, factory name or trademark". Various types of transport vehicles and handling rules used for transporting products shall comply with relevant national regulations. During transportation, the wooden case shall not be placed horizontally or obliquely, and the length direction shall be the same as the moving direction of the transport vehicle. Rain proof measures shall be taken. The stored products shall be stored vertically in a dry room. The future development of upgrading the consumption structure of residents, encouraging independent innovation of enterprises, new rural construction and urbanization process will ensure that the medium and long-term demand growth trend for glass products in the domestic market will remain unchanged. With the development of construction, automobile, decoration, furniture, information industry technology and other industries and the improvement of people's requirements for living space environment, functional processing products such as safety glass, energy-saving insulating glass have been widely used. The supply and demand pattern and consumption structure of flat glass are changing. The development of the glass industry is connected with many industries of the national economy, and the glass industry plays a positive role in promoting the development of the entire national economy. Therefore, the 11th Five Year Plan also puts forward specific requirements for the development of glass industry. Various laws and regulations have also been promulgated to regulate the healthy development of the glass industry. In the new situation, the glass industry must change its growth mode and effectively adjust its industrial structure in accordance with the requirements of the Scientific Outlook on Development in order to promote the healthy development of the industry. Features of tempered glass Strength improvement: the mechanical strength, impact resistance and bending strength of tempered glass can reach 4-5 times of that of ordinary glass. 2. Improved thermal stability: tempered glass can withstand huge temperature difference without damage, and its resistance to temperature change is 3 times that of ordinary float glass of the same thickness. 3. Safety improvement: after the toughened glass is damaged by force, it quickly presents small obtuse angle particles, thus ensuring personal safety to a large extent. Applications: furniture, electronics and electrical appliances industry, construction, decoration industry, bathrooms, cars, escalators, and other places where safety is especially needed and temperature difference changes sharply, and can be used as the original piece of insulating glass and laminated glass. 6mm12mm, Standard for nominal thickness of glass D Tempered glass GB/T9963-1998 GB/T531-92 Vulcanized rubber Shore A hardness test method GB1216-85 Outside micrometer GB4871-1995 Ordinary flat glass GB5137.2-1996 Test method for optical performance of automotive safety glass GB11614-89 Float glass JC/T677-1997 Test method for uniform static load simulation wind pressure of glazing Henan Fuxin Glass Co., Ltd. Main business: 15mm19mm super length; Ultra wide tempered glass and laminated glass. Ultra white glass toughening and SGP lamination; Fireproof glass. The larger processing size is 3.3 * 16m. In addition, glass engineering design; Install. If necessary, please contact: Liu Ke 13918139656
