ENERGY-SAVING POWDER COATING OVENS
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Our thermocatalytic ovens can flow and cure powder coatings in about a third of the time taken by a hot air oven,often even faster.
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In a conveyorised process oven, these time savings translate directly into savings in floor space, plant and conveyor requirements.
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Energy use per product is ofter a fraction of that required by a hot air convection oven.
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Products are brought to flow/gel temperaturecatalytic oven for powder coating-side view (typically 180 degrees C) very rapidly and without the need for forced air movement thereby minimising powder loss and improving finish quality.
Complete flow and bake ovens
Case Study: thermocatalytic oven bakes powder onto aluminium castings in 7 minutes
1. The products (aluminium air-filter cartridges) are powder coated in our test center and suspended in our test oven.
For increased flexibility our adjustable test rig is not housed in any enclosure, therefore whatever results are achieved here will be surpassed by any actual production oven (which of course will have its own stainless steel lined, double-skinned and insulated enclosure). The trials indicate that the required residence time will be between 7 and 8 minutes.
2. The resultant thermocatalytic production oven consists of 4 off 2-m sections each containing 8 of the biggest Bruest heaters, making a heat-zone 8 meters long.
3. The thermocatalytic oven is capable of curing a variety of different colour powders onto a wide range of products from large aluminium cylinders hung individually to jigs full of smaller parts.
4. Even the heaviest parts require only 7 minutes.
Ramp ovens for powder flowing/gelling only
Where a hot air oven already exists it can be more cost-effective from a capital expenditure perspective to use the thermocatalytic heaters just to “ramp” products up to the desired temperature and then use the existing oven just to hold the products at bake temperature.
Case Study: APW Electronics, Eastleigh, Hampshire
Thermocatalytic oven flows powder in 60 seconds.
- The customer powder coats metal enclosures and bakes them in a hot air convection oven.
- The powder stoving schedule calls for 10 minutes at 180 degrees C.
- However, the bigger, heavier parts take over 9 minutes just to reach flow temperature (during which powder can get blown or shaken off the product) resulting in a total oven residence time of 19 minutes.
- The customer wanted to increase line speed from 1.5 meters per minute to 2-meters per minute, but their hot air oven just could not cope by itself.
1. Prior to installation of the ramp oven, even the flat sheet metal products cannot be processed at the desired line speed.
2. Sample products are powder coated in our test center and suspended in our test-oven. Tests are done on a worst case basis, the biggest parts are 850 mm wide, 850 mm tall and 1,500 mm long, weighing 60 kg.
3. Being fully adjustable, the test rig has no enclosure, so the test results achieved here will be surpased by the production oven which will have its own stainless steel lined,double-skinned and insulated enclosure. Trials indicate that the powder will flow in just over a minute.
4. The thermocatalytic ramp oven is positioned immediately at the entrance to the existing hot air oven
5. The ramp oven consists of just one 2-m section, containing 8 Bruest heaters.
6. The long-wave infrared from the heaters is absorbed rapidly by the powder coating. The 2-m long ramp oven flows the powder in 60 seconds, allowing the line speed to be increased by one third, to 2 meters per minute.
Finish quality is greatly increased because the powder is already flowed before it enters the convection oven for baking. Additionally, the hot air oven’s burner ,which had been struggling, now uses considerably less gas.
