Getting Glass Annealing Right with Shortwave IR
If you’re tempering glass, you know the struggle. You need those thermal gradients to be spot on. But moving from batch processing to a continuous inline flow is a different beast. You need a heat source that kicks in instantly and disappears just as fast. That’s where shortwave infrared (SWIR) lamps come in. Instead of wasting time heating up the air around the glass, these lamps shoot energy directly into the material. It’s much more efficient. The problem with lag In a production line, the glass doesn’t stop. Period. We use shortwave quartz lamps because they hit full power in milliseconds. It’s practically instant. This means you can tweak your heat zones on the fly while the glass is moving on the conveyor. If you use slower heaters, you deal with thermal lag. And lag is a nightmare—it creates uneven stress in the glass, which usually means it’ll just shatter the moment it hits the quench phase. Managing the heat High-wattage SWIR tubes are great because they punch through the glass surface quickly. But there’s a catch. When you cram that much power into a small space, the housing gets incredibly hot. If your cooling fans and vents aren’t up to the task, you’re going to fry your wiring and connectors. It’s a simple mistake, but it’ll kill your hardware fast. Keeping things running We stick with standardized connectors so that when a tube eventually gives out, you can just swap it and get back to work. No one likes downtime. We also use high-purity quartz; it ensures the lamp doesn’t soak up the IR energy itself, but pushes it all into the glass where it belongs. A couple of pro tips for the setup: Keep an eye on your voltage. Spikes are the enemy of the filament and will shorten the life of your lamps. And for heaven’s sake,keep your reflectors clean. A bit of dust on those mirrors can tank your efficiency by 10-15%. When that happens, your lamps have to run hotter to make up the difference, and that’s a one-way ticket to a burnt-out tube.