Another 50 to 70 per cent less friction
The patented two-component sealing lip bonds elastomer and PTFE permanently: the elastomer provides the flexibility, the applied PTFE membrane reduces friction — depending on the friction conditions by a further 50 to 70 per cent compared with an already friction-optimized VR seal.
What the PTFE membrane changes
Friction
50 to 70 % less than the standard VR sealing lip, depending on the friction conditions.
Dry running
Greatly improved dry-running behavior — safe use even under difficult lubrication conditions.
Heat
Less heat generated at the sealing point, and therefore less thermal load on the elastomer.
Leakage
Minimized leakage across the whole service life.
Speed
A higher surface speed is permissible than with comparable standard solutions.
Installation
A stiffer sealing lip — installation becomes easier and more forgiving.
What that means per sealing point
The starting figure comes from our worked example for a gearbox in a production environment. The third column is derived from it, not measured separately.
| Version | Friction power | against standard |
|---|---|---|
| Standard shaft seal to DIN 3760 | 60 W | — |
| VR rotary shaft seal | 20 W | −67 % |
| VR Low Friction | 6–10 W | −83 to −90 % |
The third row follows arithmetically from the 20 watts of the VR version less the 50 to 70 per cent that the PTFE membrane saves on top. What that means in your case depends on speed, pressure, medium and operating hours — which is what the savings calculator is for, and, in case of doubt, us.
In five designs up to a housing Ø of 110 mm
The Low Friction sealing lip is available for designs DOA, DOB, SOA, SAB and SAC. The housing diameter D2 goes up to 110 mm; above that, please talk to us.
Above 110 mm, and for applications that call for a different design, the friction-optimized standard version remains the right choice — it is still at about one third of the friction power of a standard shaft seal.
Where it pays off
- Food production
- Medical technology and pharmaceuticals
- Motorsport up to Formula 1
- Marine and subsea
- Defense
- General mechanical engineering: compressors, rotary unions
A case from motorsport
The Formula Student team at Bonn-Rhein-Sieg University fits its planetary gearbox inside a 10-inch wheel. There, every watt of power loss is a watt that never reaches the road — and every millimeter of space is already spoken for. The narrower design allowed smaller, lighter housing parts, and the lower friction reduces losses in the drivetrain.
The unit price is not the price
A VR seal costs more than a catalog part. What it actually costs, though, is decided not at the seal but at three places next to it.
No hardening, no nitriding, no hard chrome plating, no liner. For the running surface the steels usual in mechanical engineering are enough — in many cases unhardened standard stainless steel. The low contact pressure of the preloaded diaphragm is what makes this possible.
The figures for your drawing20 watts of friction power instead of 60 per sealing point. On two shifts that is 160 kWh, 82 kg of CO₂ and €32 per sealing point per year. A plant with 40 sealing points therefore saves around €1,280 — every year, without anyone doing anything for it.
Calculate with your own figuresLess friction means less heat, less wear and longer service intervals. And because no running-in mark is worn into the shaft, the shaft stays as it is when the seal is changed.
To friction powerThe friction figures come from a typical gearbox in a production environment, calculated at €0.20 per kWh and 0.512 kg of CO₂ per kWh. We are happy to work out what your own plant would save in your specific case.
Every design, material and size in one PDF
60 pages of design know-how: pressure and p-v diagrams, design guidelines, the elastomer overview and the complete size table with 541 sizes. You receive the link by e-mail straight away.
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