Getting Infrared Heating Right for Those Massive Glass Tunnel Kilns
If you’re running a glass finishing line with a tunnel kiln, you know the struggle. You need a very specific heat profile—if it’s off by a bit, your glass warps or it doesn’t cure evenly. And once your span hits over 2 meters? Forget about off-the-shelf lamps. They just aren’t built for that. That’s why we build custom continuous infrared units. We design them specifically for those huge footprints.
The struggle with power and length
Here’s the thing: when you build a lamp longer than 2 meters, you start fighting voltage drop and uneven heat. Nobody wants “cold spots” right in the middle of their tunnel. To stop that from happening, we make sure the wattage per centimeter stays exactly the same from one end to the other. We usually go with high-voltage setups. It keeps the current manageable, which means we don’t have to run ridiculously thick wiring to feed the whole array. It just makes the whole setup cleaner.
Quartz and the “breathing” room
We use high-purity quartz glass for the tubes. Why? Because it can take the hit of rapid heating and cooling without just snapping. To get that solid wall of heat, we line the lamps up in parallel banks. But we have to be careful with the fit. We use special end-caps and connectors that give the glass room to move. If you clamp a quartz tube too tight, it’ll crack the second it gets hot. It needs to expand. We leave a calculated gap so the tube can basically “breathe” as it heats up.
What to watch out for
These units are great for getting the high heat density you need for rapid tempering or curing. They’re built to drop right into your existing kiln dimensions without a headache. But a heads-up: pushing that much power through a long tube is risky if your power supply jumps around. You could burn them out. To keep things running, you’ll need a precise PID controller and a cooling system that actually works. If the air doesn’t move inside the housing, those connectors will overheat and fail. And that’s a phone call you don’t want to make on a Friday afternoon.