The Benefits of Using a Ferrofluidic Seal
A Ferrofluidic seal provides a hermetic seal under both static and dynamic conditions against gas, vapor and other contaminants.
There is virtually no friction between the rotating and stationary components in a Ferrofluidic seal, so the seal does not wear. The seal lifetime depends on the application, but many Ferrofluidic seals have been in operation over 10 years without maintenance.
A Ferrofluidic seal contains a simple permanent magnetic circuit and low volatility ferrofluid. The only parts subject to wear are self-contained ball bearings which are engineered to provide reliable operation.
Since there is no mechanical friction within the ferrofluid or between the ferrofluid and the static seal components or shaft, no particles are produced which could contaminate the system. Low vapor pressure ferrofluids maintain seal integrity even in high vacuums better than 10-9 mbar.
Ferrofluidic seals provide hermetic sealing even at high rotational speeds. Current technology has produced configurations that perform at dN values of 500,000 (where d=shaft diameter in mm and N=rotational speed in rpm). For a 1" feedthrough this equates to a rotational speed of 20,000 rpm.
Optimum Torque Transmission
Through-shaft construction permits 100% of the engineered torque transmission and provides in-phase rotation without backlash or slip errors.
No Set-Leakage Failures
Ferrofluidic seals provide leak-free performance, even in intermittent and static conditions. Unlike elastomeric seals, they are not subject to plasticizing and relaxation effects during idle periods.
The low viscous drag of the ferrofluid is independent of the pressure applied across the seal.