Noise, vibration, and harshness (NVH) describes how a product behaves in terms of sound. It’s an important design consideration for the automotive industry, but NVH also applies to manufacturers of industrial machinery, heavy equipment, and specialty vehicles.
This article from Elasto Proxy describes noise, vibration, and harshness and how the door and window seals, acoustic insulation, and vibration mounts that we provide help manufacturers to reduce NVH. Keep reading to learn more and contact us to discuss your application.
What is Noise?
Noise, or unwanted sound, is measured in decibels (dB). Loud, intense sound at 140 dB or higher can cause pain or hearing loss in humans. That’s why occupational health and safety regulations limit the number of decibels in workplaces such as factories.
Even at lower decibel levels, noise is still a problem. With cars, a squeak is more than just an annoyance. Consumers are less likely to buy or recommend a vehicle with poor acoustical performance. They’re also more likely to return the car to the dealership for warranty repairs.
To an extent, noise is also subjective. The rumble of a diesel engine may appeal to a driver but irritate pedestrians. The electrification of vehicles and equipment poses its own challenges. Without the roar of an engine, drivers tend to hear more road noise and vibration-induced sounds.
What is Vibration?
Vibration is the rapid, back-and-forth motion of an object. The number of times that these oscillations occur in one second is called the frequency and the unit of measure is Hertz (Hz). The human ear can’t hear frequencies below 20 Hz, but vibrations above this produce audible sounds.
In manufactured products, vibrations aren’t just a problem where they occur. That’s because they can travel from their source. In heavy equipment, the path that vibrations take might be metal part that extends from the engine bay to the operator cab. Window glass also transmits vibrations.
Vibrations aren’t just an irritant. They can harm people and equipment. Excessive vibrations from manually operated machinery can injure a worker’s hands or arms. With machines, vibrations can accelerate wear. They can also cause equipment to use more power or need unplanned repairs.
What is Harshness?
Harshness isn’t measurable, but that doesn’t mean it’s meaningless. In the automotive industry, it affects ride quality. Harshness also influences perceptions of quality overall. If a truck door makes an unpleasant sound as it’s closed, the decibels or frequency aren’t what people notice.
For manufacturers, it’s better to address NVH during the initial design stages than to find out that there are problems with prototypes or, even worse, finished products. By partnering with Elasto Proxy, you can address NVH with door and window seals, acoustical foams, and vibration mounts.
Door and Window Seals
The door and window seals on vehicles and equipment are easy to overlook but impossible to ignore if there’s a problem. Poorly made seals can allow more than just water and weather to enter. They can admit outside air that causes a whistling sound. Road noise also becomes more noticeable.
With car doors, consumers want to hear a deep, solid sound that suggests a well-made product. The right rubber seals can help. Well-made gaskets can also keep doors and windows from rattling. Like car buyers, heavy equipment operators notice noises that suggest poor workmanship.
When you buy door and window seals from Elasto Proxy, you’ll get products that are cut with precision on our water jet equipment. We also offer a choice of bonding methods for gasket joints that last. In addition, we can help you to compare weather-resistant seal materials.
Acoustic Insulation
The acoustical foams you can buy on-line or from Big Box stores are fine for residential or commercial applications, but manufacturers need industrial-grade solutions. Inside heavy equipment cabins, headliners absorb sounds. Side panels, floors, and floor mats also support quieter cabins.
Elasto Proxy specializes in custom acoustic insulation. Our water jet equipment cuts foam materials to size to fit cabin contours. We can also laminate different materials together into a sandwich-style structure that combines sound absorption with sound blocking and vibration damping.
For example, Elasto Proxy can laminate a washdown-capable vinyl facing to a sound-absorbing polyurethane foam. Then, on the other side, we can apply a pressure-sensitive adhesive (PSA) with a removable liner for ease-of-installation. We can also laminate acoustical foams to rubber flooring.
Vibration Mounts
Vibration mounts are rubber-to-metal bonded assemblies that attach to vehicles, machinery, and equipment. The rubber reduces vibrations and the metal defines the component’s shape, style, and strength. Vibration mounts typically have tapped holes and use threaded fasteners.
Elasto Proxy supplies vibration mounts that provide isolation or damping. Vibration isolators are installed at or near the source of vibrations, such as an engine. Vibrations dampers are installed where vibrations need to be reduced, such as where they pass through a vehicle’s chassis.
Heavier products usually need larger or more numerous vibration mounts. That’s also the case if the weight of a system isn’t distributed evenly, or if there is more weight in some locations than others. For example, a dump truck that’s loaded with rocks is heavier in the dump bed than in the cabin.
Reduce NVH with Rubber Products from Elasto Proxy
Does your company make vehicles, equipment, or machinery? Do you make assemblies or subassemblies like operator cabs, doors, or windows instead? By reducing noise, vibration, and harshness, you can improve product quality and perceptions of quality. Take the first step by contacting Elasto Proxy.
