Fixing the Heat Headache in KHS Blow Molding
Ever notice your bottles coming out a bit wonky? Maybe the walls are too thin in some spots, or the whole shape just looks off. Usually, it comes down to one thing: uneven heat. When those original SMI SR 12 lamps start to age, they don’t just dim—they shift. You get these “cold spots” in the oven that mess up the preform stretch. It’s frustrating. We build drop-in replacement lamps that fix this by matching (or even beating) that original heat pattern.
Getting the Power Right
The SMI SR 12 system is picky about wattage and voltage. If the numbers are off, the infrared heat doesn’t penetrate the plastic the way it should. We keep our voltage tolerances tight. Our shortwave lamps hit the heat ramp-up fast, which is exactly what you need when you’re running high-speed PET lines. If you’re dealing with thick-walled preforms, you’ll love the heat density. But a quick heads-up: if you push for higher wattage, your cooling fans have to work harder. Keep your ventilation clean. If the vents are clogged, you’re just asking for a burnout.
No More “Cold Ends”
Here’s a common problem with generic lamps: “end-loss.” You’ll see the heat just drop off near the connectors, leaving the ends of your preforms under-heated. We solved that by using high-purity quartz glass and a different way of centering the filament. It flattens the heat curve. The result? The preform gets heated evenly from top to bottom. And don’t worry about the installation. We use standard industrial connectors, so you can just plug them into your existing sockets and get back to work.
Real-World Results
You don’t need to spend a fortune on OEM parts to get the heat field you need. You can just swap these in during your next scheduled downtime. Because we’re obsessive about the coating and the filament geometry, you won’t see those annoying “stripes” that cheap replacements often leave behind. Your operators will notice it almost immediately—fewer rejects, more stable bottles, and a lot less stress throughout the shift.