25.01.18 • In conjunction with Freudenberg Sealing Technologies GmbH & Co. KG, SEW-EURODRIVE GmbH & Co. KG has developed the new Premium Sine Seal sealing system, which optimizes lubrication in the sealing gap, cuts friction and wear and increases sealing reliability.

Drives in industrial applications are increasingly operated around the clock with high dynamics in alternating directions of rotation, frequently up to 8000 operating hours a year. Under these loads, the seal can be often the limiting component in a gearmotor in terms of service life.

As with a conventional oil seal, the functional principle of the Premium Sine Seal is based on a contact elastomer sealing lip. However, unlike conventional oil seals, the contact for the Premium Sine Seal is sinusoidal rather than linear.

The heat generated in the sealing gap is thus transferred to a larger surface. As a result, the elastomer is subjected to much less thermal stress and therefore ages more slowly. The sinusoidal part of the combination seal has been enhanced for gear unit sealing on the motor side based on the extremely positive experiences with the combination sealing system from SEW-EURODRIVE for the output gear unit shaft. Unlike the output gear unit shaft, the radial misalignment of the shafts on the motor side can be disregarded. The new Premium Sine Seal on the motor side thus doesn't need an oil seal spring or additional "conventional" oil seal part, as is the case with the combination sealing system at the output.

The sinusoidal shape of the sealing lip actively supports the replacement of lubricant in the sealing contact. Any dirt particles are "pumped" away from the sealing contact point, which also reduces wear. Numerous tests at SEW‑EURODRIVE using the Premium Sine Seal sealing system with extremely high dynamics (a total of several 100 000 hours for all gear units tested) show clear advantages over standard sealing systems. The tests demonstrated that the wear of the sealing lip is reduced by 50% on average. The new sealing system completely eliminates run-in on the shaft.

The results show that the expected service life of the Premium Sine Seal sealing system is more than doubled compared to standard systems. Initially, the new Premium Sine Seal is available for synchronous servo gearmotors from the CMP.. series and for MOVIGEAR® mechatronic drive systems in combination with a selection of synthetic lubricants. In a second phase, it will also be available for asynchronous motors, as well as other compatible lubricants.