In this article we explore the topic of NVH (noise, vibration, harshness), the significance of noise reduction in the automotive industry, and the best lubricants which can be used to reduce noise in cars.
The Significance of NVH
NVH refers to noise, vibration and harshness. Researchers in the field of NVH deal with the adjustment and modification of the noise and vibration characteristics of cars, trucks and other types of automotive vehicles. The noise, vibration (a measurable quantity) and harshness (a subjective quality) emitted by vehicles are sources of complex challenges in the automotive industry. These include the comfort level of the occupants of a car, or the extent to which the car disturbs the people around it.
Almost all NVH characteristics originate from the mechanical interactions between the plastic and metal parts, or in-between the tires. Using lubricants on these parts is the most appropriate solution for this problem.
Using Lubrication to Reduce Noise in Cars
In order to reduce wind noise and prevent the entry of water and dirt, elastomeric protection strips are used to seal automobile doors, sunroofs and rear covers. However, the protection strip itself sometimes becomes a source of unwanted noise due to the combined movement of different components.
PFPE oils, like the Krytox GPL series, are used throughout the industry to tackle these types of problems. They are an ideal solution thanks to their excellent resistance to rain, car washes and harsh chemicals on the road; low volatility and resistance to drying; and compatibility with chemically sensitive elastomers.
Advantages of Krytox Lubricants
- Work in a wide range of temperatures
- Easy to apply
- Extremely compatible with metals
- Reduce leakage
- Low viscosity
- High compatibility with different materials
- Ability to stay where it’s applied
Convertible Roof Noise
A major motor manufacturer in the United States, along with an Italian supplier of solar panels, offered a new convertible roof to give its customers a closer contact with nature. There were three parts to the new construction: two removable roof panels and a metal trim. The problem was that the joints squeaked due to vibration. Therefore a noise reduction solution that could operate at any temperature between 40 and 100°C was required.
A Krytox Automotive Series Oil was chosen for its EPDM compatibility and ease of application using a simple brush at the assembly stage. The product was rigorously tested and the result was the disappearance of noise, thanks to NVH lubricants.
Reducing Car Interior Noise
A squeaky and vibrating car interior can be perceived by customers and critics as a sign of poor quality in a market as competitive as the automotive sector. This is why manufacturers take measures designing increasingly silent interior systems. These are tested in difficult road conditions and in closed circuit laboratory conditions. However, when it comes to automotive interiors, while the plastics used may be inexpensive, provide dimensional stability, and aesthetic, they often tend to squeak when coming into contact with other materials.
High performance NVH lubricants like Krytox GPL205 can solve this problem. Its polymer compatibility, low volatility and resistance to evaporation over the life of the vehicle ensures the elimination of squeaks from the start.
Reducing Noise in Seats
A Brazilian manufacturer of luxury car seats was receiving complaints to the point of having to recall products due to annoying squeaks originating from the metal headrest slides. The rods had not been lubricated, but the manufacturer realised the need to exceed customer expectations.
NVH lubricants were the answer. The Krytox team recommended a light oil for its compatibility with metal guides and its ease of application. Low viscosity Krytox oil is able to stay where it’s placed. This is due to its high surface applicability, creating a very thin film of lubricant.