Friends who know tempered glass know that improper operation of the tempering furnace may cause wind spots on the glass, which will affect the beauty of the glass. What is the wind spot? How to avoid wind spots during the operation of the tempering furnace?

　　1. What is wind spot

　　Wind spots are also called stress spots. Under polarized or partially polarized light conditions, such as the bright northern sky or sunlight reflecting from the necessary polarization angle of the glass, the internal stress of the tempered glass (the original glass that has been tempered by the tempering furnace) causes the glass to double Optical effects caused by refraction.

　　(After multiple pieces of glass are stacked, the clear "dark path" is the wind spot)

　　The wind pattern has the same effect as a rainbow. It may be like a checkerboard, a chain, or perhaps more because the air nozzles of the commonly used horizontal glass tempering furnaces and car glass tempering furnaces appear as multi-circle markings. This multi-circle stress Spots are usually seen in the reflected light of cars, especially when using polarized sunglasses or polarizing clips, because polarized glass can only pass through polarized light, and tempered glass is like a partial polarizer.

　　2. The composition of wind spots;

　　Wind spots are usually formed by uneven cooling of the tempered glass during the production process of the tempering furnace. Stress spots can sometimes be seen on tempered and heat-strengthened glass. Stress spots that can be seen under certain light conditions are a feature of all tempered and heat-strengthened glass, and cannot be regarded as product defects. Stress spots that can be seen under certain light conditions cannot be eliminated. To a certain extent, it is also a characteristic point for identifying toughened glass. The presence of wind spots indicates that the glass must be thermally strengthened. However, the well-designed tempering furnace can minimize the visibility of stress spots.

　　The stress spot of tempered and semi-tempered glass seen under certain light conditions is an optical phenomenon similar to grating diffraction. When visible light contacts thermally strengthened glass (tempered and semi-tempered glass), light waves are transmitted at different speeds on the x (width) axis and y axis (length) of the glass sheet. This optical phenomenon is called grating (light polarization). The phenomenon is due to the surface compressive stress and central tensile stress of the glass, which come from the glass tempering or thermal strengthening process. In fact, light polarization is an inherent property of heat-strengthened glass, which can be used for non-destructive testing of the external surface compressive stress of tempered and semi-tempered glass by optical instruments such as DSR (Differential Surface Refractometer) and GASP (Contact Angle Polarimeter). The tempered glass has obvious wind spots

　　3. Effective control of wind spots;

　　Reason 1: After the glass is out of the oven, the swing button of the air grille is interrupted, so that the wind nozzle of the glass is constantly blowing on a part of the glass. Treatment method: the swing of the air grille must be carried out consistently, and we must promptly when the glass is broken in the wind grille Organize.

　　Reason 2: The height of the wind grid from the glass is too low. Treatment method: We appropriately increase the height of the wind grid without affecting the particle size and other quality requirements of the glass. But this is the processing method when the glass is made, and the general product is after It's hard to deal with!

　　The above is the method of dealing with wind spots during the operation of the tempering furnace compiled by the editor. If you want to know more, please continue to pay attention to us.