How to Quiet an Oil-Less Air Compressor?

Since the onset of the industrial era, noise pollution has become synonymous with mechanical industries. Whether it’s a large-scale production plant or a home-based workshop dedicated to DIY projects, some machines are at the root of all the commotion, and air compressors are one of them.

As one of the most fundamental and powerful machines in a mechanical workshop, air compressors exhibit extreme noise levels, at times close to 80 dB to 90 dB. Despite the fast booming technology in the mechanical sector to curb excessive noise, the recent entrant to the air compressor lineup – the oil-less air compressor – is just as loud as its former counterparts. We have shared some practical ways to quiet an oil-less air compressor. 

Oil-less air compressors are undeniably noisy, mainly because of the compressor size, loud exhaust, and breached air intake tube. Wrap the compressor motor with sound-deadening material and mount a rubber grommet to soak up vibrational noise. Attach an air intake silencer and place your oil-less air compressor in a noise reduction box to suppress the ear-deafening noise.

Why Do Oil-Less Air Compressors Get So Noisy?

Be it the traditional oil-lubricated compressors or modern oil-less versions; air compressors emit alarming noise levels. Portable oil-less compressors, like the pancake, may sound subtle, but they are only suitable for small-scale DIY projects. Standard industry-level air compressors are noisy, and there could be multiple reasons for that:

Compressor Size

Not all air compressors are built for the same purpose, nor do they have an equal capacity for thrusting air. Industrial air compressors rely on powerful motors with massive intake and pumping volumes. While they cater to large-scale assembly line requirements, you cannot overlook the intensity of noise they produce as a consequence. That’s why factories often take dedicated measures to reduce compressor noise and attain a safe working environment.

Breach in Air Intake Tube

The air intake tube is often the loudest part in an oil-less air compressor. As the compressor rotates, it sucks air from the surroundings into the intake tube. The incoming air thrashes against the flapper valve, especially in case of leaks, causing it to vibrate with each impulse.

Though the vibration is quite a distraction in itself, it also spreads to the neighboring components, such as the pulley and filters, causing them to rattle forcefully. It is a standard practice to set the air intake tube away from the actual compressor unit to dissipate the noise effectively. 

Vibrating Components

Although the rattling from the air intake tube spreads to surrounding parts quite easily, there are multiple sources of vibrations in an oil-free air compressor. Most vibrational noise is linked to loose components like air filters, pistons, and valves.

If the vibration is coupled with a loud clanking noise, chances are, the motor has become loose and is hitting against the casing. It is important to ensure that all internal air compressor mounts are tightly secured against the casing during the assembly.

Blowing Exhaust

The sudden thrust of compressed air as it expands out from the compressor exhaust is associated with a loud blowing noise. While it’s less intensive than the noise from the air intake valve, compressor exhaust emissions are still largely distractive. The expelled by-products from the combustion process may also lead to turbulence, indicating an even louder noise.

Ways to Quiet an Oil-Less Air Compressor

For an oil-less air compressor that gets the job done efficiently, the staggering noise levels between 40 dB to 90 dB are considered quite normal. But to give you a perspective, listening to sounds above 70 dB over a prolonged period can damage your hearing. So, if your air compressor generates noise above the safe limit, you must figure out solutions to quieten it.

Install a Muffler on Oil-Less Air Compressor Intake

While one can’t disregard the impact-driven vibrational noise, nothing compares to the intensity of airborne noise an air compressor emits. Like combustion engines used in automotive vehicles, oil-less air compressors also need specialized silencers that dampen the excessive noise without undermining its motor’s performance.

Air Compressor Silencers are instated with air filters that muffle the incoming air in a compressor unit, reducing the noise by 2 dB. It may not seem much compared to the true intensity of noise being emitted, but the 2 decibels certainly matter when working the 10-hour shifts. Intake silencers are the most viable solution for treating low-frequency air compressors operating at 370 revs per minute.

Build an Air Compressor Noise Reduction Box

Maintaining a productive workspace seems impossible as long as a thundering air compressor unit keeps barging in at your ears. If you have some room to spare aside from your workshop, move the air compressor unit to a separate, more isolated spot for better noise reduction.

Although it helps settle the noise, it may not be a feasible solution for home-based workshops, which brings us to the second solution – the air compressor noise reduction box. Setting up a noise-insulation box around the unit will buffer most airborne noise.

An enclosed container without proper ventilation may overheat the machine. Make sure your noise reduction box has individual openings for the air intake, exhaust unit, and power outlets. Setting up air compressors in a separate room or dedicated soundproof enclosures can cut down noise emissions by 25%, saving you from the constant bombardment.

Conduct Regular Maintenance For Oil-Less Air Compressor 

Regular maintenance and upkeep are essential regardless of the air compressor being set up outside or packed in the corner of your workshop. Like any other machine, oil-less air compressors also deteriorate and malfunction over time, often denoted by unconventional noises.

Despite being called oil-less compressors, they require oiling as part of lubrication to ensure all moving parts are working smoothly. As part of the regular maintenance, you need to ensure all components are tightly fastened, air filters are clean and unclogged, valves are open, and belts and gaskets are grease-free. If you don’t consider yourself eligible for the job, have an expert examine your unit.

Clad the Air Compressor Motor With Sound-Deadening Material

Even if the air compressor motor is tightly secured, the sheer thrust of the pistons causes it to vibrate. If not restrained in time, the slight vibrational hum would turn into a loud rattling and spread to other components. However, cladding the motor casing with sound-deadening material can dampen the vibrational noise by up to 20%.

You can find scores of noise-dampening materials online, but the best ones are Siless Liner and MLV Sheets. When soundproofing the oil-less air compressor, be moderate. Don’t overdo the cladding to the degree that it subdues the ventilation needs of the compressor.

Modify the Oil-Less Air Compressor for Noise Reduction

If you know your way around machines – or compressors, to be specific – and consider yourself to be quite an expert, modifying certain parts can help reduce noise without losing performance. You should consider instating steel springs and Rubber Grommets around the motor unit to soak up the vibrations before reaching the rest of the components.

Grease up the machine parts that slide against each other such as the motor pistons and air valves, to eliminate chances of clanking. Some home-based mechanics cover the compressor units with Sound Blankets to amplify muffling. But to achieve better results, prefer aligning it with other oil-less air compressor soundproofing methods.

Oil-Lubricated vs. Oil-Less Air Compressors – Are They Worth It?

Oil-less air compressors have impacted the mechanical infrastructure, thanks to their high efficiency and eco-friendliness. But are these reasons enough to compel you into buying an oil-free compressor? Or, more importantly, are oil-less compressors worth it when it comes to noise?

Despite slightly older technology, oil-based air compressors are more durable and robust than their modern counterparts. The lubrication oil also keeps the compressor’s internal infrastructure cooler, which improves its efficiency despite staying functional for hours.

Since lubricated compressors are less likely to break down midway, they’re set up in large-scale assembly lines. However, the bulky setups and regular maintenance requirements make them unfeasible for small workshops.

Oil-less air compressors, on the other hand, demand less maintenance and are portable enough to set up in home-based workstations. Even though they lack the durability lubricated versions bring, oil-free air compressors are eco-friendly with no burden on the earth’s natural resources. So, if that’s what you stand for, oil-less compressors should be your go-to choice.

People Also Asked

This FAQ section addressed a few questions for quick reference:

Are oil-less air compressors quieter than traditional compressors?

While it’s widely held view among mechanics that oil-less air compressors are quieter than oil-based versions, it’s not actually the case. In fact, they are comparatively louder than traditional compressors. Since there’s no lubricating oil to smoothen the moving components, except grease, they become noisier due to excessive vibrations.

How long does an oil-less air compressor last?

There’s no definite lifespan for an oil-less air compressor; however, it can last for about 10 years with proper maintenance and upkeep.

What is the best way to quiet an oil-less air compressor?

There are multiple ways to quiet an oil-less air compressor, but some work better than others. Installing an air intake muffler or compressor silencer will effectively reduce air compressor noise. But before you apply any of the methods, set up your compressor far from your actual workspace.