How to actually get consistent heat in extra-long glass tunnels
Most infrared lamps stop at about a meter. That’s fine for small jobs, but if you’re running a massive glass tunnel, you’ve got a problem. You can’t just line up a bunch of short lamps and hope for the best. You’ll end up with cold spots at every single joint, and in the glass world, a cold spot is a disaster. That’s why we build continuous heating units that stretch past 2 meters. No gaps. No guesswork. The struggle with heat distribution The goal is simple: you want the heat to be flat. But when you’re dealing with a 2-meter run, physics tries to fight you. You run into voltage drops, and suddenly the wattage isn’t hitting the tube evenly. If you aren’t careful, the center of the lamp burns out while the ends are barely warm. We spend a lot of time obsessing over the filament winding and voltage. We do this to kill the “zebra effect”—those annoying alternating stripes of hot and cold that ruin a tempering or bending process. You just want one smooth, steady heat. The nuts and bolts At this length, things get heavy and fragile. We use heavy-wall quartz because a 2-meter tube wants to sag under its own weight. But here’s the tricky part: the tube needs to breathe. We use precision brackets that let the glass expand and contract as it heats up. If it can’t move, it snaps. Simple as that. On the power side, we usually wire these into high-voltage circuits. It keeps the current manageable, but it means you need to double-check your cabling. This is a massive amount of heat in one spot. If your cooling fans and exhaust hoods aren’t up to the task, you’re going to cook your own control electronics. Why this matters for your glass These units are built for the long haul—literally. Because the heat is continuous, your glass glides through the tunnel without hitting any temperature dips. It keeps the internal stress low and the quality high. Plus, it’s a much cleaner setup. You’re getting rid of a dozen clunky connectors and failure points, replacing a fragmented mess with one solid run. It just works better.