Stop the Chipping: Why We Preheat Glass with IR
Let’s be honest: glass is a pain to work with. It’s brittle. When you hit a cold sheet of glass with a cutting tool, it doesn’t always behave. You get those annoying little chips or “corner breakouts” that ruin a perfectly good piece. The fix? Heat it up first. We use infrared (IR) preheating to take the edge off—literally. By warming the glass before it ever touches the blade, the material relaxes. It’s less of a shock to the system, which means your edges stay clean and smooth.
Getting the Most Out of Your Lamps
Here’s the thing about IR lamps: they throw heat in every single direction. If you just hang a lamp over a conveyor, half that energy is just heating up your machine frame. That’s a waste of money and power. To fix this, we use gold or aluminum reflectors. They act like a mirror for heat, bouncing all that energy right back down onto the glass. It lets you hit your target temperature way faster without having to crank the wattage so high that you fry your wiring.
It’s All About the Balance
But you can’t just blast the glass with heat. If you end up with “hot spots,” you’re actually making things worse. Those uneven temperature jumps create their own stress, and that’s how you get cracks. The trick is getting the heat to feel the same across the entire width of the sheet. We spend a lot of time tweaking the spacing of the lamps and the angle of the reflectors. If it’s not uniform, it’s not working.
The Trade-offs (The “Real World” Stuff)
Now, you might think, “Why not just use the most powerful lamps possible and speed up the line?” Well, there’s a catch. High-intensity short-wave lamps are fast, but they’re hungry. They put a massive strain on your power supply, and if you push them too hard, the tubes burn out way faster than they should. And then there’s the heat soak. If your cooling fans aren’t up to the task, the housing around those reflectors can actually warp. Once your mounts warp, your focal point is gone, and you’re right back to square one with those jagged, chipped edges. It’s a balancing act between conveyor speed, heat output, and cooling. Get that right, and everything just flows.