The term ‘coolant’ seems pretty straightforward – it’s something that cools things down. The reality is a little more complex. A coolant has two main uses: lowering temperatures and providing lubrication. These two roles create a perpetual cycle in a sense, especially in the metal industry. Here’s how it works. You might remember from your school science lessons that metal is a good conductor. That means it can get hot or cold quite quickly, usually by drawing heat from the things around it.
So, for example, when you touch a metal spoon, it feels cold on your skin. This is because it rapidly ‘pulls’ your body heat, leaving you with a cold sensation. Similarly, when you put a ladle or spoon into hot food, the metal is scorching when you place it on your tongue or hand – because it instantly absorbed the heat from the dish. Now let’s look at this characteristic in an industrial setting. The metal parts of the machine pull heat from the manufacturing process itself, so they generally remain hot. Also, many times, the metal parts of the machine grind and rub against each other. This generates heat too.
If you’ve watched those sword-making videos online, or those stereotypical cameos that ‘represent industry’, you’ll have noticed that moulding metal requires intense heat to begin with, because you have to melt the metal, cast it, or beat it into shape. So whichever portion your metal is involved in, it’s going to get really, really hot. Of course, the other side of being a good conductor is that metal releases heat as fast as it acquires it. It’s basically a champion of heat transfer. In the earlier example, the cold metal warms up in seconds as it matches your body temperature, and the hot spoon cools fairly fast as well.
When metal meets air
That said, air is a poor conductor, so while the metal is all too willing to share its heat, its elevated temperature takes a while to spread into the air. The air just isn’t as willing to share. This is where coolants come in. They can be gas or liquid, water-based or oil based. And they have higher conductivity levels than the open air. So when a coolant is run over hot machine parts, they cool down faster. Certain types of coolants – called cutting fluids – are also used for lubrication. coolants smoothen the grinding of metal parts, so less heat is generated.
But why do these machines need to stay cool? If the metal parts are too hot in – say – a engineered plastics factory, they can burn the material, marring the final product. And if the grinding metal parts aren’t lubricated, they wear out faster and scratches or blemishes appear on the ground finished product. In both cases, this can lead to your metal machinery collapsing, which causes stoppage in the production line. Repairs can be pretty expensive too. So, coolant increases the quality of your final product and extends the lifespan of your machine. It cuts down servicing costs too.
Coolant is expensive though, so you don’t just use it once. You can recycle it, but even if you’re going to throw it away, you have to clean it first. Filtration ensures metal shards and other contaminants don’t get into the ground or sewer systems. Here at Interfil, we have a trusted range of coolant filtration equipment, from centrifuges to magnets, plus the Industrial filtration media that goes with them, so talk to us about your coolant cleaning needs.
For a locally made, high-quality solution to coolant filtration, call Interfil today on 02 9533 4433.