2-Min Technical Tips: Reducing Bottom Surface Tempered Glass Marking
A small defect or mark is easily visible on glass products. The most common tempered glass marking is caused by the contact of the ceramic rollers and the bottom surface of the glass. HHH recommends two best practices to avoid this marking:
- cleaning regularly your furnace ceramic rollers
- using a dry lubricant for tempering ceramic rollers like SO2 to act as a buffer between glass and the rollers
Learn why using a dry lubricant such as SO2 can temporarily prevent tempered glass marking in our 2-minute technical video.
SO2 is a dry lubricant used in gaseous form and injected into the tempering furnace to use as a buffer between the ceramic rolls and the bottom surface of the glass. SO2 is intended to either eliminate, minimize or reduce to acceptable levels, the amount of bottom surface marking from contaminants and/or heating imbalances.
The SO2 is merely meant as a crutch to allow you to continue production until you get to a point where you can clean the ceramic rolls to prevent the heat stain. HHH, like the bulk of our industry, feels that the use of SO2 is merely a band-aid when the root cause for this type of marking, usually referred to as heat stain, is contaminated rollers or heating imbalances.
Properly cleaning your rollers at a frequency to maintain the desired quality levels of your glass; that’s the key to minimizing the bottom surface marking without using SO2.
Do you have any questions regarding the use of SO2? Give us a call.
If you’re noticing light marking on your glass, it may be time to check your ceramic rollers and use an appropriate lubricant. Let’s talk! Give us a call at 336-439-1574.