Overband · drum · head-pull
- ✓ For bulk flow on a belt
- ✓ Overband, head-pull, drum types
- ✓ Continuous operation — high capacity
- ✓ Heavy industrial applications
Conveyor Belt Magnetic Separators
Conveyor belt separators remove ferrous particles from bulk material carried on a belt. The point where they differ from free fall and pipeline solutions is scale: here tons of material an hour move on an open belt, in an environment that is often dusty and subject to impact.
Three layout types
| Type | How it is positioned | When it is preferred |
|---|---|---|
| Overband (suspended belt magnet) | Suspended above the belt, across or along the flow; it throws the metal it captures to the side with its own belt | On lines with continuous and heavy metal ingress; discharge is automatic |
| Head-pull (head pulley) | The pulley at the discharge end of the conveyor is magnetic | No extra space is needed, since the material separates as it is already falling |
| Drum (drum magnet) | A rotating drum placed at the point where the flow discharges | On high capacity lines needing continuous separation |
Why a separate solution is needed
The material layer on a belt is thick. For the magnet to reach a particle in the bottom layer it has to produce a deeply penetrating field; that is why these separators are physically larger than the free fall types. As the layer thickness increases the capture rate falls — which is why the magnet is positioned where the material is spread thinnest, preferably at the discharge end.
Areas of application
Recycling plants, mining, cement, bulk chemicals and refuse-derived fuel production. On these lines metal threatens not only product quality but also the life of the downstream equipment; a bolt entering a crusher can cause a stoppage lasting days.
What to watch for when choosing
- Belt width and speed — the magnet must cover the belt width completely
- Layer thickness — the most decisive parameter; a thick layer needs a stronger and more closely positioned magnet
- Suspension height — being adjustable allows fine tuning on site
- Discharge method — manual cleaning, or a self-discharging belt construction
- Environment — in dusty and damp environments the protection class becomes important
In closed pipelines pipeline separators are used, and on lines flowing by gravity free fall separators.
Verification after installation
Once the magnet has been positioned, a verification should be carried out under real production conditions: whether a sample metal piece placed under the belt is captured is tested at different layer thicknesses. The suspension height is fine tuned according to that test; the value determined by calculation usually needs correction on site.