This article was first published in Powder Coating magazine, November 2014
Gas Catalytic IR – 3:1 Rule Provides Key to Success
The use of Gas Catalytic IR technology in the finishing, curing and drying industries has now become so well accepted that more and more companies are not asking: “Will it work for me?”, but “How soon do we make the change?”. The understanding of the advantages of the technology has improved dramatically over recent years, but it is worth reviewing the most quoted rule of thumb, relating to Gas Catalytic IR, the 3:1 rule, and looking at a couple of examples that demonstrate why it is often quoted.
What is the 3:1 Rule?
Stated simply, the 3:1 rule says that for every three minutes it takes to cure a part in a conventional convection oven, it will require only one minute in a Gas Catalytic IR oven. So, for example, parts that normally take 30 minutes to cure conventionally, only take 10 minutes in a Gas Catalytic IR oven. Obviously, it is not exact across a wide range of parts; some take less time (thin sheet metal parts for example) and some take slightly longer (heavy, geometrically complex parts). But the 3:1 rule is a good place to start when considering the most appropriate curing technology to use. Why is the 3:1 Rule so Important? The most obvious answer has to be the fundamental fact that it demonstrates that less energy is required. But sometimes overlooked is the additional fact that the reduced gas consumption has a further level of control which is achieved by the use of zones and PLC controls. But, it does not stop there. A further look into the “knock on” effects, show that for a given track speed, less time in the oven, means a shorter oven is required; smaller form factor means more efficient use of manufacturing space. So the opportunity for overall manufacturing cost reduction becomes a reality.