What substances do magnetic separators typically protect?
Magnetic separators are effective in any sector which has risk of ferrous particle ingress. Safety critical processes such as food, pharmaceuticals and chemicals use both primary and secondary separators to protect powders, granulates and liquids. Typical examples being flour, starch, sugar, chocolate, tea and cereal.
In other industries such as recycling and construction materials primary separation may be adequate, typical examples include cement, aggregates, wood chips, plastic or glass recycling.
Is the magnet type important when it comes to select the right magnetic separators?
Different magnet materials have different properties, so the choice is very important. The latest high intensity magnetic separators use Neodymium (NdFeB) (also known as Rare Earth) magnets. This is the strongest magnet material and is effective in extracting the finest ferrous and paramagnetic particles.
Depending on the intensity required for the application, Neodymium magnets are available in strengths typically between 7,000 and 12,000 Gauss, the higher the Gauss number the stronger the magnetic force. Samarium Cobalt and Ferrite (Ceramic) magnet materials are also available often for applications where the particle size is larger, or the magnetic field needs to be projected further. These materials typically have a weaker magnetic strength (circa 3000 Gauss) but can withstand higher temperatures and exposure to corrosive elements.
These are not recommended for safety critical applications such as food or pharmaceutical. In a magnetic separator the magnet is contained in tube or cover. When specifying the magnetic strength, it is important to check with the manufacturer that the Gauss reading is taken on the outside of the tube or cover as this will be a true measure of the magnets’ effectiveness.
Where can magnetic separators be installed?
Magnetic separators are ideal for many different installation points on gravity, free-fall, pneumatic, pumped or conveyor feed processing lines. Either at raw materials intake to check incoming ingredients, mid-production at HACCP points or protecting finished product at the end of the process on bulk discharge.
Typical installation points include gravity-fed chutes, pre and post sifting, bulk tanker discharge, ingredient sieving, pre and post mixers, vacuum or pneumatically lines, grain tips, sack rip and tip stations, above or below transfer conveyors or vibratory feeders.