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Sag bending is a glass processing method that involves heating the glass to a specific temperature and then bending it to a desired shape using a mold. For laminated windshields, this process is done at a lower temperature range to prevent the plastic interlayer from melting or degrading. Typically, the sag bending process is done at around 550-630°C for a few minutes until the glass reaches the desired shape. The exact temperature range and duration of the process can vary depending on the specific type of glass and the desired shape.

What is Sag Bending

What is Sag Bending

During sag bending, an enamel paint is used to help maintain the glass’s shape. This type of paint can adhere to the glass at the temperature at which it is shaped in the mold and hardens as it cools. Enamel paint is typically applied to the glass surface using a serigraphic printing process. The thickness of the enamel layer can vary depending on the thickness and shape of the glass being processed. However, the enamel layer is generally around 27-40 microns thick.

After being sag bent, glass is chemically toughened and laminated.

Caitian and Kolhis is a leading innovator in the production of automotive glass enamels . We are dedicated to continuously developing new generations of black glass enamels designed to work with the latest developments in furnace technology. Our automotive glass enamels and black obscuration bands are specifically formulated to meet the rapidly changing glass specifications demanded by the auto industry. With our state-of-the-art technology, we are able to meet the most exacting standards of automotive glass production, ensuring our products are of the highest quality.

Tailored to meet essential requirements, our heavy metal-free enamels for automotive glass sag bending processing offer a broad firing range, superior gloss, optimal opacity, and the deepest possible shade of black.

As the name suggests, it refers to a photovoltaic cell module formed by two pieces of glass and solar cells composed of a composite layer, and the cells are connected in series and connected in parallel to the lead ends. In recent years, double sided glass solar panels are like riding on a rocket, and their popularity is soaring. Why are they so popular?

Advantages of double sided solar panels:

  • It has a higher life cycle power generation, which is 21% higher than ordinary components.
  • The abrasion resistance of the glass is very good, which also solves the problem of wind and sand resistance of the components in the field. Where there is heavy wind and sand, the wear resistance of double-glass components is obvious.
  • The warranty for ordinary solar panels is 25 years, and the warranty for a double-glass photovoltaic solar panel is 30 years.
  • The insulation of the glass is better than that of the backplane, which enables the double-glass module to meet higher system voltage, so as to save the system cost of the entire power station.
  • The attenuation of traditional solar panels is about 0.7%, and the attenuation of double-glass solar panels is 0.5%.
  • The fire rating of double-glass solar panels has been upgraded from C-level to A-level of ordinary crystalline silicon modules, making it more suitable for residential houses, chemical plants, and other areas where fire hazards need to be avoided.
  • The water permeability of the glass is almost zero, and there is no need to consider the hydrolysis of the EVA film induced by water vapor entering the module. The back sheet of a traditional crystalline silicon solar panel has a certain water permeability. The water vapor of the back sheet makes the inferior EVA resin quickly resolve acetic acid, which leads to electrochemical corrosion inside the module, which increases the occurrence of PID attenuation and snail marks. The probability. It is especially suitable for photovoltaic power plants in seaside, waterside, and high humidity areas.
  • Glass is inorganic substance silica, which is the same substance as sand everywhere, and its weather resistance and corrosion resistance are more than any known plastics. Ultraviolet rays, oxygen, and moisture cause the backplane to gradually degrade, and the surface is chalked and broken by itself. The use of glass will solve the weather resistance problem of the components once and for all, and will also end the dispute over which PVF or PVDF is more weather-resistant, not to mention the weather resistance, poor water resistance PET backsheet, coated back sheet, and other low-end back sheets. . This feature makes the double glass module suitable for photovoltaic power plants in areas with more acid rain or salt fog.
  • Double-sided solar panels do not need an aluminum frame unless there is a lot of dew on the glass surface. Without the aluminum frame, the electric field that causes PID cannot be established, which greatly reduces the possibility of PID attenuation.

Scope of application:

Double glass solar panel: suitable for photovoltaic power plants in residential houses, chemical plants, seaside, waterside, acid rain, or salt fog areas.

Single-glass solar panel: suitable for industrial applications, with relatively high environmental requirements and low water permeability.

  • Low-E stands for “low emissivity”, which means that the glass has a low rate of emitting radiant heat.
  • Low-E glass is coated with a microscopically thin, transparent layer of metal or metal oxide. This coating reflects heat back to its source, keeping heat inside during winter and outside during summer.
  • Low-E glass can have different levels of solar control, which determines how much visible light and solar heat can pass through the glass. This is measured by two metrics: visible light transmission (VLT) and solar heat gain coefficient (SHGC).
  • Low-E glass can also have different levels of U-value, which measures how well the glass insulates. The lower the U-value, the better the insulation.
  • Low-E glass can help reduce energy costs by reducing the need for heating and cooling, and can help regulate the temperature and humidity inside a building.

Online Low-E Glass:

  • Online Low-E glass is produced by applying a thin layer of metallic oxide during the glass manufacturing process.
  • The coating is fused to the glass while it is still in a molten state, resulting in a durable and scratch-resistant surface.
  • Online Low-E glass has a higher solar heat gain coefficient (SHGC) than Offline Low-E glass, meaning it allows more solar energy to pass through the glass.

Offline Low-E Glass:

  • Offline Low-E glass is produced by applying a thin layer of metallic oxide to pre-cut glass sheets.
  • The coating is then cured in a heat treatment process, resulting in a durable and scratch-resistant surface.
  • Offline Low-E glass has a lower solar heat gain coefficient (SHGC) than Online Low-E glass, meaning it allows less solar energy to pass through the glass.
  • Pre-firing is a process used in the manufacture of automotive glass. It involves applying a layer of enamel to the glass surface and then firing it at a low temperature to partially cure the enamel. The purpose of this process is to prepare the glass for subsequent processing, such as bending or laminating, without compromising the integrity of the enamel layer.

    During the pre-firing process, the glass is heated to a temperature range of 550-630°C (1022-1166°F) for a period of 1-5 minutes, depending on the type and thickness of the glass. This temperature range is lower than that used for sag bending, as pre-firing is designed to partially cure the enamel layer, not fully bend the glass.

    The enamel used in pre-firing is typically a black glass enamel, applied using the screen printing method. This enamel helps to block out unwanted light and reduce reflections, improving the overall appearance of the glass.

    It is important to note that pre-firing should be performed by skilled technicians using specialized equipment to ensure consistent and reliable results. The use of high-quality enamel and precise control of temperature and firing time are critical to the success of the pre-firing process.

    In conclusion, pre-firing is a crucial step in the production of automotive glass, providing a foundation for subsequent processing and improving the final appearance of the glass.