halogen lamp quartz halogen heat lamp infrared heater blow molding pet blow molding machine

July 23, 2026

Getting Your PET Preform Heating Right with Quartz Halogen Lamps

If you’re working with PET preforms, you know the drill. You need that plastic softened just right before it hits the blow mold, or the whole batch is scrap. That’s where quartz halogen infrared heaters come in. The cool thing about these lamps is the halogen cycle. It keeps the tungsten filament at a steady temperature, so you don’t have to worry about the heat dropping off as the lamp gets older. It just keeps working. The physics part (simplified) We build these lamps to push out short-wave infrared radiation. In plain English? The heat punches right through the PET wall quickly. You aren’t wasting energy heating up the machine frame or the air around it. If you go with a high-wattage tube, you get a denser heat flux. That means faster cycles. Just a heads-up: make sure your wiring and power supply can actually handle the voltage and current. If you skimp there, you’re just asking for a premature burnout. Why quartz? We use high-purity quartz glass for the envelope because it’s tough. Really tough. It handles thermal shock way better than borosilicate, so it won’t crack when you’re cycling the lamps on and off all day. When it comes to swapping them out, we mostly use R7s or Sk15 connectors. They snap right in, making maintenance a breeze. You might see some versions with a special coating to reflect the heat or focus the beam. They’re great, though they might take a few extra seconds to warm up at the start. Putting it all together in the oven In a blow molding machine, these lamps sit in oven banks. The goal is a perfectly even temperature across the preform. Here’s the problem: if one lamp fails or the wattage drifts, you get “cold spots.” That leads to bottles with uneven walls, and nobody wants that. One last thing to watch out for. High-density halogen arrays gethot. Like, really hot. Make sure your cooling fans are actually moving enough air. If they aren’t, you’ll end up warping your lamp holders or frying your electrical contacts. Not a fun way to spend a Tuesday.