Synchronous magnetic couplings to transmit high torques through membranes without dynamic seals

Magnetic couplings are generally used to transmit torque from one system to another where the magnetic transmission is required to maintain a hermetic seal to prevent leakage and contamination. The couplings are synchronous and the output shaft speed is exactly equal to the input speed and these types of coupling can be designed with a maximum 100% efficiency.

Magnetic couplings are widely used in pump systems to isolate the electrical motor from the liquid. This has the advantage of removing the dynamic seals which have a finite lifetime and are prone to leakage, which can cause failure of the machine and contamination of the working fluid. A membrane/seal wall is located in the magnetic gap between the rotors providing complete isolation between the wet and dry systems. Magnetic couplings can also be used to introduce compliance into the drive train and can ultimately be used as a torque fuse to protect the system drive components.

Advantages

• Low cost
• Very high efficiency
• Robust
• Overload protection
• Eliminates dynamic shaft seals
• Tolerate shaft misalignment

Magnomatics have extensive modelling capabilities for optimising couplings, in terms of obtaining precise pull-out torques, torsional compliance, electromagnetic losses in conducting membranes, in order to achieve the most compact device for given operating conditions.