Normally the glass thickness is thicker than 10mm is called thick glass. Before the glass is fed into the tempering furnace, the temperature should be lowered to the minimum heating temperature, because the thick glass need longer low temperature, to avoid the glass broken due to the fast temperature increasing. The speed to fed into the furnace and heating reciprocating should be slowed down, to guard the frequency changer against heavy load from excessive current. To reduce the heating reciprocating could low the probability of bursting.
When change the thin glass to the thick glass, the thick glass couldn’t fed into the furnace immediately, the heating switch should be turned off with 2～4 minutes. When the temperature is lowed, then to turn on the heating switch, to avoid the tempered glass low quality because of the sudden high temperature. When blowing, it is better to choose the axial fan. If using the fan with high power, the tempered glass quality is easily affected by different wind pressure. The glass edges, holes and gaps should be ground well by diamond wheels.(When tempering, the thicker glass should have better grinding edges than thinner glass)
When setting the temperature, for the 12mm thickness glass, temperature should be around 675℃～685℃. For the 15mm thickness glass, temperature should be around 665℃～675℃. For the 19mm thickness glass, temperature should be around 655℃～665℃.
When setting the heating time, for 12mm thickness glass, the heating capacity should be 38～43s every millimetre. For 15mm and 19mm thickness glass, the heating capacity should be 43～50s every millimetre. If the glass have holes or gaps, the heating time should be longer than normal glass by 2.5%～6%.
Post time: Sep-15-2022