Non-contact magnetic torque-transfer assemblies for pumps, mixers and sealed equipment, engineered around torque, air gap, containment material, pressure, temperature and speed.
Pole count, magnet grade, air gap and steel circuit define torque capability.
Barrier thickness, conductivity and corrosion compatibility can be as important as the magnets.
Concentricity and axial position affect torque and bearing loads.
Conductive metal cans can create eddy-current heat at speed; material/thickness should be optimized.
| Element | Design choices | Engineering effect |
|---|---|---|
| Outer driver | NdFeB / SmCo magnet ring or segmented assembly | Torque density and temperature |
| Inner driven rotor | Magnet assembly / pole pieces / hub | Torque transfer and inertia |
| Containment can | 316L / Hastelloy / PEEK / ceramic / project-specific | Pressure, chemistry and eddy-current loss |
| Air gap | Magnet-to-can / can-to-magnet spacing | Torque vs mechanical/pressure margin |
| Alignment | Radial / axial runout and concentricity | Torque ripple, heat, bearing load |
| Protection point | Rated vs decoupling torque | Overload behavior and safety margin |
| Application / Architecture | Typical Configuration | Engineering Focus |
|---|---|---|
| Chemical / process pump | NdFeB or SmCo inner/outer rotor + containment can | Torque, corrosion, pressure, eddy loss |
| Mixer / agitator | Radial coupling across sealed vessel wall | Air gap, torque margin, alignment |
| Vacuum / clean system | Hermetic magnetic drive | Barrier material and zero dynamic shaft seal |
| High-temperature drive | SmCo coupling | Thermal stability and containment material |
| Parameter | Capability / Options | Notes |
|---|---|---|
| Magnet material | NdFeB / SmCo | Temperature / torque / corrosion driven |
| Containment can | 316L, Hastelloy, PEEK, ceramic, project materials | Thickness and conductivity affect torque / eddy loss |
| Air gap | Minimized but mechanically safe | Gap directly affects torque density |
| Torque rating | Defined at operating gap / temperature | Include startup / transient margin |
| Speed | Application-specific | Balance, eddy-current heating and retention reviewed |
| Pressure / leak | Project-specific | Pressure or leak method must be agreed |
Agree normal, startup and overload torque
Select material, pole count, geometry and gap
Rotor hubs, can, bearings / interfaces as scoped
Controlled orientation and retention
Torque characterization, runout and leak/pressure test where required
Characterize breakaway / transmitted torque at defined gap and temperature.
Containment can tested to customer-defined method where part of supply scope.
Mechanical alignment measured relative to defined datums.
Customer can see the torque or dimensional test live before shipment where practical.
| RFQ / DFM input | What to provide |
|---|---|
| Torque | Nominal / startup / peak |
| Speed | Operating / maximum rpm |
| Temperature | Fluid and ambient / magnet temperature |
| Containment | Material, thickness, pressure and media |
| Envelope | OD/ID/length, shaft or hub interface |
| Validation | Torque test method, leak / pressure, runout, documentation |
A thicker or more conductive barrier can increase air gap and eddy-current losses. PEEK/ceramic minimize eddy losses; metal barriers can offer mechanical and corrosion advantages.
NdFeB maximizes torque density at moderate temperature; SmCo is attractive for higher temperature and corrosion-critical systems.
Yes, the test method should be agreed with operating air gap, speed/temperature assumptions and measurement setup.
Both routes can be discussed: magnet sets, rotor subassemblies or a complete engineered magnetic coupling depending on project scope.
We can review magnets, mechanical retention, interfaces, magnetization, inspection and supply as one program.
A smaller magnetic gap generally increases torque density but may reduce mechanical/pressure margin.
Metal containment cans can create eddy-current heating; speed, wall thickness and conductivity must be considered.
SmCo is preferred when thermal stability dominates; NdFeB can maximize torque density in lower-temperature systems.
Chemical compatibility, purity and pressure requirements determine the containment material.
| Input | What we need |
|---|---|
| Rated / peak torque | Nm and duty cycle |
| Speed | RPM and operating profile |
| Temperature | Continuous and peak |
| Fluid / environment | Chemical compatibility, cleanliness, corrosion |
| Pressure | Normal / design / proof where applicable |
| Envelope / shafts | Available OD/ID/length and interface drawings |
Static or dynamic torque verification according to the agreed method.
Mechanical alignment of driver, driven unit and containment interfaces.
Applied where the scope includes a pressure boundary and a defined test method.
Project-specific evaluation where eddy heating or high-speed behavior is critical.
Selected final tests can be shown/recorded before shipment for remote customer confirmation.
