A Lifetime of Lubrication for Smooth Operation and Noise Mitigation in Sunroof Systems
There are multiple application areas within a sunroof system that require lubrication from either a mechanical (drive system, control brackets, slides) or a noise mitigation (moving panels, roof system frame, body structure, weather stripping) standpoint. The movement of metal on plastic, weather stripping to glass or painted surfaces, among others, can generate noises typically described as squeaks, itches, or judders. When failure of these components is not an option, whether because of durability, warranty, safety, loss of productivity, or downtime, Krytox™ products are an ideal solution for the automotive sunroof industry.
Krytox™ performance lubricants are fully synthetic perfluoropolyether (PFPE) oils and greases. They offer an exceedingly long life and outstanding properties for the prevention of noise, vibration, and harshness (NVH) and superior lubrication of mechanical systems.
- Ability to survive extreme temperatures and water washout
- Non-damaging to plastic or elastomers
- Noncorrosive to metals
- Extended lubricant life due to low volatility and outgassing
- Nonhazardous and nontoxic
- Indefinite shelf life if unopened and stored in a clean, dry location
- Both oils and greases are suitable for automated spray application
Krytox™ GPL 205 Grease
Krytox™ GPL 205 grease is a polytetrafluoroethylene (PTFE)-thickened PFPE oil that contains no additives and can be used on various components, including those that are exposed to harsh environmental factors such as rain, snow, dust, salt, cleaning and car care products, and common automotive fluids. Krytox™ GPL 205 has been widely used by OEMs in mechanical sunroof systems and seals.
Krytox™ AUT 2604 Grease
Krytox™ AUT 2604 grease contains PFPE oil and a special PTFE thickener for enhanced performance in mechanical application areas of sunroof systems. Designed to provide a thin, long-lasting, and even film on contact surfaces, it promotes smooth motion. Krytox™ AUT 2604 is specifically formulated for a broad temperature range, exhibiting very good low temperature characteristics, as well as enhanced load and wear performance at high temperatures.
Krytox™ GPL 105 Oil
Krytox™ GPL 105 oil is a clear, colorless, fluorinated synthetic PFPE oil designed to reduce friction and wear, while extending equipment life in severe duty applications. Krytox™ GPL 105 oil has been used by OEMs to prevent weather stripping issues on sunroofs, such as NVH (noise, vibration, and harshness) and BSR (buzz, squeak, and rattle) that can occur over a vehicle’s lifetime.
The application of Krytox™ GPL 105 oil to weather stripping offers enhanced protection from damaging ultraviolet (UV) rays in sunlight.
Krytox™ AUT U14 Oil
Krytox™ AUT U14 is a proprietary blend of PFPE oils containing a dye that, when exposed to a UV or “black light” gives off a yellow-green color. This allows visual confirmation of coverage for quality control purposes, as illustrated in the pictures below:
Like Krytox™ GPL 105, Krytox™ AUT U14 combats NVH and BSR problems and helps protect seals and weather stripping in automotive sunroofs from UV damage.
Microscopic images show that Krytox™ AUT U14 wets the surface of weather stripping more uniformly than other PFPE offerings, including standard GPL 105 oil. This leads to a lower static and dynamic coefficient of friction, reducing slip-stick and noise in sunroof systems.
Figure 1 shows a non-treated weather stripping surface.
Figure 2 shows how a standard PFPE oil can pool unevenly on the surface.
Figure 3 shows how the special formulation of Krytox™ AUT U14 provides uniform coverage of PFPE oil.
Zins Ziegler Analysis
When an automobile is in motion, contacting surfaces elastically deform and store energy. When this energy is released, it can produce noise in the form of audible squeaks or rattles.
Zins Ziegler is a standard automotive industry test apparatus for measuring the noise potential of different material pairings. It measures static and dynamic coefficients of friction between material pairings to calculate a risk priority number (RPN). The test method uses standard protocols to simulate driving cycles up to 100,000 kilometers. Material pairings with a high RPN are more likely to have stick-slip issues and produce noise.
The table below illustrates how the presence of environmental contamination (dust) greatly increases the RPN number between weather stripping and painted panels, thus increasing the propensity to create noise.
Coating the weather stripping with Krytox™ AUT U14 reduces the RPN number compared to untreated or a competitive PFPE coating.
Zins Ziegler Analysis with China Dust
Krytox™ lubricants are chemically inert and compatible with virtually all automotive construction materials, including paint finishes, seal materials, glass, leather, textiles, plastics, and metals.
Source: Krytox Performance Lubricants