Hollow glass has good insulation and sound insulation effects, which can reduce building energy consumption, save energy, reduce noise, and improve the environment. In addition, using insulating glass can simplify the structure, reduce weight, increase lighting, and reduce costs. Therefore, insulating glass is widely used in building curtain walls and doors and windows. Developed countries (such as Nordic countries) have laws that require the use of insulating glass in building curtain walls and doors and windows, and the use of insulating glass in China is also becoming increasingly widespread. In the production and use of hot bent (bent tempered) insulating glass, it is necessary to pay attention to several issues;
1、 Hot bending of glass
Hot bending is required to have good appearance quality. Therefore, high-quality float glass raw sheets should be selected, and suitable hot bending molds and scientific and reasonable hot bending processes should be used. Hot bending glass products should have a smooth surface, no obvious spots or pits, and composite product size tolerance requirements. In addition, considering the consistency of lamination, the two pieces of synthetic insulating glass must be hot bent in pairs to ensure good fit.
2、 The shortcomings of hot bending (bending tempered) insulating glass
High grade hot bent (tempered) insulating glass requires not only the characteristics of insulating glass, but also low optical distortion to better observe objects in the field of view through the glass. This characteristic indicator is not specified in the GB11944-89 national standard for insulating glass or the JB/ZXXXX-XX hot bent glass industry standard. This is because this new product has not been introduced for a long time and people's expectations for it are relatively low in architecture, On the other hand, it is also related to the prevalence of this problem and the difficulty in determining indicators.
Automotive laminated glass has a high requirement for optical distortion, as the visual duality can easily lead to fatigue and traffic hazards. Compared with hot bent laminated glass, hot bent insulating glass will result in greater optical distortion and distortion rate compared to a pair of glass with the same hot bent quality. Therefore, hot bent insulating glass is not used in transportation vehicles, and the optical distortion index of automotive safety glass is also suitable for hot bent insulating glass.
3、 When using hot bent (tempered) insulating glass in high-end buildings, attention should be paid to light distortion.
According to the above, it is inevitable that hot bent (bent tempered) insulating glass will have significant optical distortion. In use, it is easy to generate duplicate images, and there is no requirement for this indicator in the labeling. Therefore, it is not suitable for use in transportation vehicles and precision observation. It is also necessary to discuss the requirements for light distortion in high-end buildings, and it is better not to use this product solution in strict places.
Although using large-scale hot bending (bending tempered) hollow glass curtain walls is beautiful and generous, attention must be paid to their optical distortion performance. With the development of China's glass curtain wall industry technology, this problem will be well solved, and corresponding standards will be introduced soon.
