First-Hand News?

Obtain news and background information about sealing technology, get in touch with innovative products – subscribe to the free e-mail newsletter.

Friction Reduction in the Seal

Weinheim (Germany), November 19, 2019. The optimum function of rotary shaft seals depends on many factors. One of them is the wettability of the sealing lip. This parameter plays a particularly important role with synthetic lubricants such as polyglycol. If wetting is too low, not only does wear on the sealing lip increase, but the contact with the rotating shaft can also damage the shaft itself. The engineers at Freudenberg Sealing Technologies (FST) and Freudenberg Technology Innovation (FTI) have developed a new coating that forms a flexible bond with the elastomer of the seal and significantly improves wetting with synthetic lubricants.

Thanks to different materials and shapes, radial shaft seals for sealing rotating shafts can be used in a wide variety of industrial applications. What they all have in common is the demand for the lowest possible friction, low wear and reliable sealing effect. Optimum lubrication of the entire tribological system depends on permanent wetting of the sealing lip. This poses a particular challenge for poorly wetting lubricants based on polyglycol, which are used in drive technology, for example in worm gears. Too little wetting increases wear on the sealing lip and can also lead to increased shaft runout due to contact with the shaft, which ultimately necessitates replacement of the machine parts.

A flexible bond over a long service life

Freudenberg Sealing Technologies (FST) has developed the new 75 FKM 585 plus coating to achieve optimum lubrication in gears and pumps with synthetic lubricants. "We have succeeded in coating the sealing lip in such a way that polar oils distribute much better," explains Dr. Matthias Adler from FST's global materials development department in the Simmerring Industry division. "The mechanics of the layer have been modified so that it forms a flexible bond with the elastic material of the elastomer over a long service life – even under dynamic load. In addition, the coating is applied where no wear occurs.” The current development was specially designed for customers who already use the standard Simmerring 75 FKM 585 in drives for which the use of polyglycol oils is recommended by the manufacturers.

The elastomer is coated using plasma-assisted chemical vapor deposition (PE-CVD). In this process, the elements in the process gas form a chemical bond with the surface of the base body. The decisive criterion for the optimization of the wetting behavior is the targeted modification of the interaction between the coating and the synthetic lubricant. The measurements show that by using special components in the new surface coating such as carbon, oxygen and silicon in a certain molar ratio, optimal wetting can be achieved compared to the standard material 75 FKM 585.

New technology can be transferred to other materials

The layer thickness of 75 FKM 585 plus is a few hundred nanometers and its properties meet the standards of the manufacturers of industrial gear units with regard to oil/elastomer requirements. Although it is designed for particularly low wear at high revolutions, it has been shown that the coefficient of friction is significantly lower than that of the standard material, even at low speeds such as in the breakaway forces and mixed friction ranges. The newly developed technology is not limited to applications with FKM, adds Dr. Adler, "but can also be transferred to other materials. Initial tests on NBR and EPDM have also shown positive results in optimizing the interaction between coating and poorly wetting oils.”

Ulrike Reich

Ulrike Reich

Head of Media Relations & Internal Communications

Telephone: + 49 (0) 6201 80 5713

ulrike.reich@fst.com

Download Documents

Download Images

Subscription service

Press Release Subscription Service

You can subscribe to the Freudenberg Sealing Technologies news alert service, bringing you the news as soon as they are published. You can always unsubscribe from this service.

Subscribe now!

Further articles with these taggings

Clever Combination

02.06.2020

Freudenberg Sealing Technologies has launched series production of a modular sealing unit that combines a classic radial shaft seal with a plastic outer case. The design promotes better long-term seal performance and longevity, is easier to assemble and significantly lowers manufacturing costs in comparison with traditional metal-encased radial shaft seal units.

Read more

Dynamic Seals Material Expertise

The Beginning of the End for the World’s Plastic Woes?

25.02.2020

Around the world, scientists have been doing research on plastics that can be totally recycled into their original raw materials. A research team in the United States has now announced a breakthrough.

Read more

Sustainability Material Expertise

Lightweight – with EMC Protection

18.02.2020

Electronic control units in cars are almost always made of aluminum. The use of plastics could trim a great deal of weight. But this requires shielding against electric fields.

Read more

Sustainability Material Expertise

All-Around Player

11.02.2020

Components made of plastic are not just lightweight – they can also handle multiple functions simultaneously. This is possible due to materials that are adapted precisely to the requirements and the high degree of flexibility available in plastic-parts production.

Read more

Sustainability Material Expertise

Steering Made Easy

04.02.2020

Freudenberg Sealing Technologies introduces a seal that comes with an integrated bearing.

Read more

Dynamic Seals

Materials for Wind Power

28.01.2020

If you were to stand a single rotor blade on end next to the Dresden Frauenkirche, it would rise more than 10 meters higher than the church’s tower cross. Without the use of composite materials, the blades of the latest wind turbine giants would be too heavy to function.

Read more

Sustainability Material Expertise

A Material from the Bark of a Tree

17.12.2019

Natural rubber, sometimes called caoutchouc, is the raw material used in making what we simply call rubber. Thailand is the world’s biggest exporter of natural rubber. It is where the first plantations and producers are turning to sustainable cultivation methods – by abandoning pesticides and monoculture, for example.

Read more

Sustainability Material Expertise

Freudenberg Develops Next-Generation Low Friction Bearing for Improved Lubrication

03.12.2019

New “scoop” feature enables applications reliant on splash lubrication to run at higher critical speeds.

Read more

Automotive Dynamic Seals

The Wedge Makes It Possible

29.10.2019

A new design concept from Freudenberg Sealing Technologies simplifies the installation of the seal between the housing and the piston rod inside a absorber.

Read more

Automotive Dynamic Seals

First Hand News

Best of all, keep up with the latest developments
with the Freudenberg Sealing Technologies newsletter.

Subscribe now!