Getting Your Adelco IR Tunnels to Actually Behave
If you’re running an Adelco tunnel oven on your PCB line, you already know the drill. You need that IR profile to be spot on so your solder paste stays consistent and those solvents actually evaporate. But here’s the real headache: when you’ve got a long tunnel, hitting a peak temperature is the easy part. The hard part is keeping that heat steady from the moment the board goes in until it comes out the other end. You don’t want a “rollercoaster” of temperature; you want a flat line. The struggle with long-distance stability We build our IR lamps to survive the grind of SMT production. One thing that trips people up is voltage drops across those long runs. If your power fluctuates, your drying rate jumps around. That’s how you end up with “skinning” on your paste, which is a nightmare to fix. To stop that, we use heavy-gauge filaments. They can handle the rapid cycling without just giving up and burning out. The nitty-gritty: Quartz and Halogen We stick with short-wave infrared here. The lamps use high-purity quartz envelopes, which basically means the IR light gets through easily instead of the lamp absorbing all that heat itself. And since nobody likes a project that doesn’t fit, our replacements are designed to drop right into your existing Adelco footprint. No hacking or modifying required. One quick tip: keep an eye on your connectors. They’re usually the first thing to go because the conveyor vibration just shakes them loose over time. We use reinforced terminals to stop that from happening. The balancing act High-wattage lamps are great for keeping the line moving fast, but they come with a catch. When you cram a lot of kilowatts into a tight tunnel, your exhaust system has to work overtime. If your ventilation can’t keep up, the oven chassis starts to “heat soak.” Once that happens, your temperature sensors start drifting, and suddenly your profile is a mess. You’ve got to find the sweet spot between your lamp wattage and your belt speed. If you push it too hard, you’ll scorch the PCB substrate. Plus, if you’ve just swapped out your lamps, do yourself a favor and double-check your PID settings. New lamps can change the radiant intensity, and a quick tweak now saves a lot of scrapped boards later.