Imagine waking up in the morning and shuffling over to the coffee maker. You pour yourself a hot cup, then reach for the sugar. As you scoop your sugar out of the bag, you notice something shiny. It’s a small shard of metal. If you had been any more tired this morning, there’s a chance you would’ve mixed it into your coffee and swallowed it. 

We’ve all come to expect perfection from our food products. Certainly no scrap metal. No nuts and bolts. No surprises. Naturally, this extends beyond the food industry. Regardless of the material running down the conveyor belt — plastics, recycled materials, etc. — purity is essential, and even the slightest contamination can have serious repercussions, whether it’s an injured consumer, a PR nightmare, or wasted product. 

Keep Your Product Pure and Keep Consumers Safe

To avoid contamination, manufacturers often rely on a series of magnetic separators that come in all shapes and sizes. However, for the removal of extremely small particles, magnetic grids are the most popular. They’re made up of a series of magnetic bars that catch ferrous material while allowing unaffected product to pass through. 

The magnetic grid is ingenious in its simplicity.  As the product passes, magnetic bars attract unwanted metal. This includes everything from a stray bit of a broken tool to barely visible iron fillings. Even better: since the bars are made from permanent magnets, they still work under wet conditions or when power is lost entirely. 

The majority of magnetic grids use powerful neodymium magnets to catch unwanted material, but thanks to their design, the magnets themselves aren’t exposed to any elements. Instead, they’re housed in protective stainless steel. This makes them easier to clean. The maintenance crew can remove the magnets from their case, at which point, the collected unwanted material falls from the grid. Then, the magnets are slipped back into place, ready to continue collection.

To further reduce the chance of impurities slipping through, some manufacturers will stack multiple grids on top of one another in alternating directions. This creates a sort of magnetic screen. In some cases, magnetic grids are placed inside hoppers — containers for bulk material that tapers down to discharge its contents. As material moves downward, the grids collect more metal dust. 

While, as described, physical maintenance is relatively easy, environmental maintenance requires more attention. Because the magnets used in the grid are often made of neodymium, they don’t do well in extreme temperatures. Their strength begins to decline at around 80°C, and it can be permanently lost if they’re exposed to high temperatures for an extensive period of time. The general rule is that neodymium magnets lose 0.11% of their strength for every degree increase in celsius. 

While certain types of magnets and even other blends of neodymium can withstand higher temperatures, they do so at the sacrifice of their strength. To select the right kind and blend of magnet, you must first know what kind of environment you intend to operate it. 

Where to Learn More About Neodymium Magnets

If you require industrial-strength magnets, look through our catalog for neodymium magnets. Not only are our products useful in a factory setting, but also in offices, construction sites, and more. If you have questions about the most suitable environment for a particular magnet, call us at 1-304-257-1193.