Metal Removed by Magnetic Separators
Metal is a major cause of equipment damage, production downtime and poor end product quality, especially when recycling materials such as plastic. So what types of metal can be found? Here are 3 examples taken directly from a UK plastics recycling plant.
- Fine metal shards and even dust – The metal found on the face of this ultra strong Rare Earth Plate Magnet is quite fine and has been lifted up out of conveyed material. Fine iron is difficult to separate and can cause significant wear to plant and also contaminate the final product. In this particular installation, Plate Magnets were used both suspended above the conveyor and positioned in chutes (where material flows over the magnet face), but fine iron can also be removed using Drum Magnets;
- Nuts, Bolts and Screws – This is a more typical example of metal contamination that tends to be either present in the delivered reclaimed plastic or introduced into the process from plant wear or during maintenance. Nuts, blots and screws cause significant damage to process plant and can be costly in terms of equipment repair and production downtime. In this installation, these ferrous metal items were removed from the product stream using a Magnetic Pulley although Drum Magnets are also used;
- A Large Spanner – An extreme, but not unusual, example of metal contamination. The damage that a tool such as a spanner can cause is huge in terms of cost and downtime. Introducing a spanner into a shredder or granulator could have disastrous consequences. The spanner in this photograph was separated using a Magnetic Pulley. On other plants both Drum Magnets and Twin Pole Overband Magnets are commonly used;
We are putting together a library of metal items that have been found in process lines and would welcome your feedback and photos. Please send us your stories to firstname.lastname@example.org and we will add these to this news blog on our website.