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The Problem Of Tempered Glass Roughness Can Be Divided Into Two Categories
Aug 15, 2017

  The problem of tempered glass roughness can be divided into two categories:

  The first type, bending tempered glass flatness is not good problem. For this kind of problem usually consider its coincidence index, when the curved tempered glass finished product is not up to the design requirements, the main will appear the following 3 kinds of phenomena:

  (1) Distortion deviation of finished glass and design requirement. This indicates the need for bending tempered glass in the position of the roller is not placed correctly, the center of the glass bending line and the roller is not parallel, if this happens, the operator needs to readjust the glass in the position on the platform, so that the center of the glass curved line and the roller parallel.

  (2) The finished glass is different from the design bending depth. This indicates that there is a problem with the setting of the tempering process parameter: During the heating stage, the heating temperature of the glass is not enough; in the cooling stage, the main wind gate is not synchronized with the downwind when the air outlet is blown, and a blow is turned on when the blow is on. If the next blow to open the air vent, then the bending depth of the glass will increase, on the contrary, the first blow on the air vent, after the formation of glass bending depth will be reduced, not in accordance with the design depth arc. The operator can readjust the process parameters and adjust the bending depth of the glass properly.

  (3) The surface quality of finished glass does not conform to the design requirements.

  The operator can adjust the bending time of the heating section and the time of the quench, or the tension of the transmission chain of the bending section, and solve the problems by adjusting the tempering process parameters or equipment.

  The second type, flat type tempered glass flatness is not good. This type of problem is mainly the following:

  (1) glass deformation caused by temperature difference in the upper and lower surface when heating

  ① tempered glass plate face upward bending. This phenomenon is due to the glass in the heating furnace, the glass surface temperature above the surface of the situation, keep this temperature state of the glass into the cooling chamber cooling, in the cooling process, when the glass upper and lower surface cooling temperature and wind pressure, and other conditions are the same, because the glass surface temperature is high, after cooling the upper surface shrinkage is greater than the lower surface, there will be a glass plate bending deformation phenomenon.

  In this case, the temperature at the bottom of the heating furnace can be raised to minimize the temperature difference on the top and bottom surface of the glass.

  ② tempered glass plate face downward bend. This phenomenon is due to the glass in the heating furnace heated, the surface of the glass under the temperature above the surface of the situation, keep this temperature state of the glass into the cooling chamber cooling, in the cooling process, when the glass upper and lower surface cooling temperature and wind pressure, and other conditions are the same, because the glass under the surface temperature is high, after cooling the lower surface shrinkage is greater than the upper surface, there will be a bending deformation of the glass In this case, the temperature at the bottom of the heating furnace can be lowered and the temperature difference between the top and bottom surfaces of the glass is minimized.

  (2) glass deformation caused by temperature difference between the center and the edge during heating

  If the temperature of the middle part of the glass is higher than the temperature at the edge of the heating furnace, the shrinkage of the middle part of the high temperature on the glass during cooling is will be greater than the temperature of the lower side of the shrinkage, when the glass is cooled to room temperature, the edge of the glass will be larger than the size of the middle part of the glass at the edge of the formation of a larger compressive stress, resulting in a glass plate facing the bending deformation of the phenomenon.

  Similarly, if the glass in the heating furnace after heating, if the edge of the temperature is higher than the temperature of the middle, then in the cooling process, the glass on the high temperature of the middle part of the contraction will be greater than the temperature of the lower side of the contraction, when the glass is cooled to room temperature, the size of the middle part of the glass will be greater than the size of the edge, forming a larger tensile stress on the edge of the glass, resulting in the phenomenon of the glass plate facing the bending deformation.





Blue Star Glass Co.,Ltd