Stop the Bloat: Getting Your IR Heat Right
Ever pull a batch of cans and see them bloating? It’s a nightmare. Usually, it comes down to a bad seal. If those gaskets don’t soften up enough during curing, you’re going to get leaks. Most people think they just need more power—more wattage. But that’s rarely the actual problem. The real culprit is usually “cold spots” in your IR array. When parts of the lacquer don’t get enough heat, the gaskets stay hard, and the seal fails.
It’s All About the Footprint
To stop wasting product, you need the heat to hit every single inch of that can the same way. Shortwave infrared lamps are great because they punch through lacquer layers fast. But the magic is in how you arrange them. If your lamps are different lengths or spaced out weirdly, you get “striping.” You’ll have one spot that’s scorched and another that’s barely warm. It’s a tight window. If your heat fluctuates by even 10%, your seal integrity just tanks. You want that gasket to hit its sweet spot—the exact temperature where it softens and locks in a hermetic seal.
Power vs. Heat
High-wattage quartz tubes are great for keeping the line moving fast. But there’s a catch. If you cram too many kilowatts into a small space, you risk creating hot spots that burn the lacquer. It’s a balancing act between how much power you’re pushing and how fast the conveyor is moving. Plus, if you’re running a high-output array, don’t forget your cooling. If your system can’t handle the ambient heat buildup, your lamps are just going to burn out early.
Cutting Down the Scrap
There is nothing more frustrating than guessing what’s happening inside the drying tunnel. Swapping out old, tired lamps for precision-matched IR tubes takes the guesswork out of the equation. Everything becomes predictable. When the heat field is flat and consistent, the gaskets soften evenly, the seal holds, and the bloating finally stops. Your scrap rate drops, and you can actually breathe again.