Fixing the Heat Headache in KHS Blow Molding
Ever notice your bottles coming out with weird wall thickness or just looking… off? It’s a nightmare. Usually, it comes down to uneven heat in your KHS machines. It happens all the time—either your lamps are getting old, or you swapped them out for replacements that just don’t hit the same thermal notes as the originals. To stop the deformation, you need a quartz IR lamp that actually keeps the heat steady from one end of the tube to the other.
The Truth About Heat
Here’s the thing: standard IR lamps usually have “cold ends” right by the electrodes. It’s a common flaw. We deal with this by tweaking how the filament is wound and getting the voltage-to-wattage ratio just right. For KHS setups, short-wave radiation is the way to go. It punches through the PET preform much faster than long-wave heat. This is great because it shaves time off your cycle and stops the outside of the plastic from scorching before the core even gets warm.
The Nitty-Gritty Stuff
We use high-purity fused quartz. Why? Because these tubes take a beating with constant heating and cooling, and we don’t want them warping. You’ll see R7s or SK15 connectors on these. They aren’t just there to make it fit. They ensure the electrical contact is tight. If that connection is loose, you get resistance, and your terminals will burn out under a heavy load. One quick tip: if you’re running high-wattage tubes, your heat density goes up. That means your oven’s airflow has to be spot on. If your cooling fans are clogged with dust, even the most expensive lamp in the world is going to overheat your preforms.
Just Swap and Go
Our high-end quartz tubes are designed to be simple drop-in replacements for KHS systems. By getting the filament centering exactly right, we kill off those annoying hot spots that cause “pearls” or burnt patches on the PET. You get a much smoother thermal curve. And the best part? You can actually push your machine speed a bit harder without worrying that your bottles are going to lose their strength. It just works.