Getting Ultra-Long Infrared Heating Right for Glass Tunnel Kilns
If you’re trying to heat a glass tunnel kiln over a stretch of 2 meters or more, you quickly realize you can’t just take a standard lamp and stretch it out. It doesn’t work like that. You run into two big headaches almost immediately: voltage drop and thermal expansion.
The struggle with long tubes
Here’s the thing about power. In a setup this long, a basic 220V line usually can’t keep the heat steady. You end up with cold spots, which is a nightmare when you’re looking for consistency. We handle this by dialing in the wattage and voltage specifically for the length. The goal is a filament that stays hot from the first inch to the last. You get this intense, deep heat that hits the glass immediately. It’s powerful. And because it works so fast, you can stop worrying about those massive, space-wasting pre-heating zones.
Picking the right gear
We house the tungsten filament in high-purity quartz. Why? Because it lasts. When we lay these tubes out, we line them up tight. If there are gaps, you get “striping”—those frustrating temperature streaks on the glass that ruin a batch. We also use heavy-duty industrial connectors. When you’re pushing high current, the contact points can get brutal, and these connectors keep the system from burning out.
The trade-offs
Now, these units put out a massive amount of energy in a very small space. That’s great for speed, but it means your cooling system has to keep up. If the air around the lamp ends gets too hot, your tubes won’t last nearly as long. It’s a simple fix, though. We usually suggest a dedicated airflow setup just to keep those connectors cool and happy. Whether you’re building a brand new line or just swapping out old gear in an existing kiln, these drop right in. It’s a pretty simple switch that just makes your heating cycle move a lot faster.