Two strengths
Permanent ceramic magnets come in standard and strong. Strong magnets are typically used only in centering and inverted applications, where the part has to be held against gravity or pulled into line.
01Engineered solution
Magnetic conveyors
Permanent magnets set into the conveyor bed hold ferrous parts against the belt. Once the part cannot fall off, the line is free to climb, descend or run upside down.
Magnets in the bed
02Principle
The magnets are in the conveyor, not the belt.
A magnetic belt conveyor is a standard conveyor with permanent ceramic magnets placed in its bed. The magnets run along the underside of a stainless-steel slide bed and attract ferrous parts through the belt, so the belt itself is ordinary and the holding force comes from underneath it.
That clamping force is what lets the conveyor do things a plain belt cannot: hold parts through elevation changes, keep them positioned for a process, and stop small parts shifting, tumbling or jamming along the run.
Other names for the same thing
Magnetic belt conveyors are also called material conveyors and belt magnetic conveyors. Material conveyors are more usually described as material handling conveyors, which covers a wider set of equipment than magnetic holding alone.
03Magnet arrangement
Strength and spacing are set by the part.
A conveyor moving nails and screws does not need the same magnetisation as one moving large, heavy components, so the field is designed per application.
Two rows, opposed
Most applications use two rows of magnets, one oriented north and the other south. Large products use more rows to add holding strength.
Spacing follows the product
Magnet rows are usually spaced at half the width of the product, so every part is held at more than one point rather than pivoting on a single row.
Field sized per application
Both the strength and the size of the magnetic field are designed for the specific part, which is why no two magnetic conveyors are configured the same way.
04Letting go
Getting the part off again.
Holding a part is straightforward. Releasing it cleanly, at the right place and without it snatching, is the part that needs designing.
The magnets stop, the part goes
Parts are released at discharge points, where the magnets leave the slider bed path. Up to that point the part is held; past it, it is free.
Easing the force off
A decreasing zone reduces magnet strength gradually so product transfers smoothly off the magnet or off the end of the conveyor instead of releasing all at once.
Slow belts and short parts
Decreasing zones are used where belt speed is below 7.62 m/min (25 ft/min), or where product length in the direction of flow is under 76 mm (3 in).
- Magnet type
- Permanent ceramic
- Strengths
- Standard and strong
- Typical rows
- Two, opposed north/south
- Row spacing
- About half the product width
- Decreasing zone below
- 7.62 m/min (25 ft/min)
- Or product under
- 76 mm (3 in) in flow direction
05Platforms
Built into standard frames.
Magnetic holding is an arrangement of a standard conveyor, so it inherits that platform's frame, tensioning and belt options.
Industrial
2200 and 3200 Series
Aluminium extruded frames with T-slot construction, sealed ball bearings, rack and pinion belt tensioning, and V-guided or non-V-guided belt options.
Sanitary
Stainless platforms
Magnetic belt arrangements can also be incorporated into the sanitary conveyor platforms where the environment requires it.
The usual platform accessories apply, since the frame is a standard one.
- Stands
- Series standard supports
- Guiding
- Range of options
- Drive
- Gearmotors and controllers
- Other
- Mounting packages, drip pans, belts
06Source case record
Buffing both faces of a hand tool.
A retained record from the archived source application set, kept because it shows an inverted magnetic run doing work that would otherwise need handling. It is not a Roarer project reference.
First pass
Hand tools are placed on a magnetic conveyor between centering guides. A magnetic bedplate holds each tool in place while a buffing wheel works one face, lightly cleaning the laser marks.
Inverted second pass
Tools transfer to a second magnetic conveyor mounted upside down, so the opposite face can be buffed without anyone turning the part over.
Release and return
At the end of the second conveyor the tools drop onto a UHMW plastic-lined chute. A third, non-magnetic conveyor returns them to the operator.
Why magnets were needed
Nothing else holds a loose tool against the belt while it is inverted and a wheel is pressing on it. The magnetic field is what makes the second pass possible at all.
07Industries
Wherever the part is ferrous.
The requirement is the material, not the sector, so magnetic holding turns up across very different lines.
Automation
Holding parts in a known position so the next machine can act on them without re-locating.
General manufacturing
Moving ferrous components between operations without the part shifting on the belt.
Integrators
Supplying the holding element of a larger line built from several machines.
Material handling
Carrying parts through elevation changes that a plain belt could not manage.
Medical
Precise placement of small ferrous components where a dropped or jammed part is costly.
Metal working
Transporting offcuts, blanks and finished parts away from presses and machines.
08Frequently asked questions
Magnetic conveyors.
What they hold, how hard, and when they release.
What can a magnetic conveyor carry?
Ferrous, iron-containing parts. The magnets attract the part through the belt, so a non-ferrous product will not be held regardless of magnet strength.
Can it run upside down?
Yes. Inverted running is one of the main reasons to use magnetic holding, and it is one of the two cases where strong rather than standard magnets are typically specified. The other is centering.
How is the magnet strength chosen?
By the part. Both strength and field size are designed for the specific product, and row spacing is usually set at about half the product width so each part is held at more than one point.
How does the part come off?
At a discharge point where the magnets leave the slider bed path. If the belt is slow or the product is short, a decreasing zone eases the magnet strength down so the transfer is smooth rather than abrupt.
Does it change the conveyor platform?
No. Magnetic holding is built into a standard frame, so the platform's frame construction, bearings, tensioning and belt options are unchanged.
09Related solutions
Often specified alongside.
Holding a part is usually in service of moving or positioning it.
Tell us the part and the run.
Give us the part material, size and weight, the elevation change and whether it has to run inverted, and Roarer can specify the magnet arrangement.
Discuss your application