Technology: Freudenberg unveils new rotary seal for process industry

Weinheim, Germany – Freudenberg Sealing Technologies has developed a new rotary seal for wet-running applications and pressures up to eight bar.

Named the Gerromatic, the seal is equipped with a wave-shaped sealing lip, not a rotation-symmetrical design. Freudenberg said this results in a sinusoidal contact pattern.

As the shaft rotates, each point of the seal lip repeatedly coats a different area of the shaft, moistening it with the medium to reduce friction and the usual temperature rise at the sealing area.

Freudenberg Sealing Technologies said experts have already demonstrated the new seal's special features at one of its testing facilities.

The Gerromatic displayed a temperature rise that was 20°C less than the increase for a standard seal.

The test was a standard wet-running trial that ran for 96 hours at five bar and a circumferential speed of five meters per second.

Under the same conditions, Freudenberg said it could only detect a "vanishingly small" leakage rate during the entire test route of more than 1,700 kilometres.

The Gerromatic rotary seal from Freudenberg Sealing Technologies is made of PTFE and produced in various versions.

It is available with food authorisations in accordance with EU 10/2011 and FDA as well as pharmaceutical approvals in accordance with the US standard USP Class VI.