Three factors of glass self explosion caused by th

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Glass knowledge: three factors that cause glass self explosion

glass explosion hurts people, which occurs frequently in major newspapers. People not only pay attention to the accidents that have occurred, but also worry about the potential safety hazards of the glass around them. However, glass cracking is an inevitable problem. Here are three important factors that cause glass cracking

there are three kinds of reasons for the influence of thermal cracking caused by glass itself: solar radiation, applied load and design factors. In addition to these three reasons, glass and frame as a whole structure also have the influence of manufacturing and assembly. The thermal cracking of building glass is a comprehensive problem. We should not only comprehensively consider the role of various factors, but also eliminate the secondary factors according to the actual project, and control the main factors. Generally speaking, there are three main factors that restrict the thermal cracking of glass:

1, the heat absorption rate of glass

because the mechanism of thermal cracking is that the glass absorbs infrared radiation in the sunlight, its temperature rises, and a temperature gradient is formed between the glass and the cold end of the edge, resulting in uneven expansion or restraint, forming thermal stress, and then making the weak part crack propagation. Therefore, the infrared absorption rate of the glass itself is a key factor. Since the wide use of heat absorbing glass, the problem of thermal cracking has become prominent. Generally, the heat absorption rate of heat absorbing glass is between 20-40%. When adopting the design of heat absorbing glass, we must make a comprehensive evaluation of the use environment and then determine it, such as the orientation of the glass, the temperature of the environment, the heat conduction of the frame and the wall, etc. special attention should be paid to the thermal explosion caused by the temperature difference. The glass absorbs heat energy, and its temperature rises. The greater the temperature difference with the lower temperature frame and wall, the greater the risk of thermal cracking. Experience tells us that thermal cracking usually does not occur in the tropics, but in the southeast facing glass in the cold or temperate zone, and the most thermal cracking occurs in the morning and morning. This is because the ambient temperature is low, although the glass absorbs infrared radiation. 1. It is easy to form a large temperature gradient with the edge after the common injection of single and double tensile machines. The use of heat absorbing glass in the above occasions should have a basis for calculating the heat absorption rate and the size of the plate surface

2. The plate size of the glass

the larger the plate size of the glass, the greater the deformation after thermal expansion, and the greater the constraint reaction, which correspondingly causes greater thermal stress and increases the probability of thermal cracking. At the same time, the larger the size of the analytical surface, the more vulnerable it is to the greater superposition effect of other loads. Therefore, while pursuing the decorative effect of large panel glass, the comprehensive effects of wind load, thermal stress, frame deformation, self weight, assembly stress and so on should be comprehensively considered. After the intelligent automation solution and heating technology of heat absorbing glass with a panel size of more than 2 have been optimized for the injection molding process m2, corresponding improvement measures should be put forward for the frame constraints

3. Processing quality of glass edge

in the thermal stress analysis, it is pointed out that the cracking generally starts from the glass edge, the tensile stress of the edge is the largest, and the processing defects of the edge are the most serious. Therefore, improving the processing quality of the edge is one of the key factors to improve the thermal cracking resistance of building glass. When the glass edge has defects, the tensile strength of the glass will be greatly reduced. During processing and installation, it is best to fine grind the glass edge and remove the seriously defective glass

in a word, in order to avoid the thermal cracking of glass, we also need to improve the raw materials, technology, process and many aspects. One day, mankind will eventually develop a glass that can ensure 100% safety for the benefit of mankind

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