How does an air compressor work

An air compressor is a machine that converts electrical power into compressed air. An electric motor drives reciprocating pistons, blowers, counter rotating screws, or other displacement equipment—which mechanically compresses the air. Most compressors are equipped with an air storage tank (also called a “receiver” or “accumulator”) to store the compressed air. Storing the compressed air reduces the number of start/stop cycles that a compressor will experience.

 

An electric pressure regulator (usually mounted on the air storage tank) senses the pressure of the stored air, and switches the electric motor on and off. For safety reasons, storage tanks are also equipped with “relief valves”. A relief valve is a small valve that is held shut with a spring. Air pressure from the air storage tank tries to open the valve (against the spring). Relief valves are designed to open (vent air from the tank) before the pressure inside the tank reaches a dangerous pressure (a pressure higher than the set point of the pressure regulator, but lower than the burst-pressure of the tank). Relief valves are specifically designed to open loudly; to alert the operator that the system is not working properly.

 

There are many different types and styles of air compressors. Compressors that are designed for temporary installation at a work site might be powered by a gasoline or diesel engine. Compressors can be bolted to the floor, free standing, mounted on a trailer, attached to its own wheeled cart, etc. Small units designed for inflating bicycle tires or beach toys are small enough to be carried by hand and stored in the trunk of a car.

 

This is a general overview of air compressors. Next, we will describe the oil free air compressor.

 

How does an oil free air compressor work

Traditional air compressors use piston rings to form a seal in the cylinders. Oil is used to lubricate these rings. This leaves a film of oil on the cylinder walls. Air that is being compressed is in contact with this oil.

 

An oil free air compressor has no oil on the cylinder walls. The pistons and/or cylinders of the compressor body are made of self-lubricating materials. A high pressure seal is created without using piston rings. No oil is used for piston lubrication, so the cylinder walls are free of oil. This provides for much cleaner compressed air.

 

Higher purity standards can be maintained with oil free compressors. In-line air cleaning devices are still needed, but the air entering the cleaning process is much cleaner to start. All air that enters a compressor will contain airborne contaminates (dust, water vapor, etc.). These contaminates need to be removed by cleaning the process air; using filters and/or dryers.

 

Reciprocal compressors that are oil free do not use rings and oil to contain cylinder pressure—pistons, cylinders, and other parts are manufactured to much finer tolerances. Precisely fitting parts contain the pressure, and provide smooth operation. Specialty material is used throughout the machine. Teflon: registered: is used extensively for piston heads and cylinder coatings. Carbon is also used for ring seals and other parts.

 

Scroll compressors that are oil free are designed so the scrolls (rotors) don’t actually touch. The scrolls pass very close to each other. With no direct contact, there is a minor loss of efficiency—but there are several huge advantages. There is no contact friction; which means less heat being generated, less wear on the scrolls, and there is no oil contamination.

 

Turbo compressors that are oil free are designed to operate without lubricants. Mechanical bearings (if used) are sealed, outside the air chambers, and don’t come in contact with the compressed air. Turbo compressors are designed so that any air escaping from the compression process passes past the bearings, and way from the compressor. Some turbos are mounted on air-supported shafts—to further reduce contamination, wear, and vibration.

 

Oil free compressors are specially designed to prevent heat buildup of the Teflon: registered parts. In many places, aluminum is used in place of cast iron—to further decrease heat buildup.

 

Oil free compressors have a much lower risk of oil vapor (and suspended oil droplets) finding its way to point of use. Every pneumatic system that is in close proximity to end-product or packaging is a potential point of contamination. Even the best maintained system runs the risk of leakage. Keeping the air supply clean is vital. This is especially true for process that uses compressed air in direct contact with end-product or packaging (inflating product, moving product with bursts of air, etc.).

 

Oil free compressors are well suited for any application where a clean, dry air supply is needed: (For example: pharmaceutical, medical labs, chemical industry, electronics, food and beverage, paint and substrate).

 

Oil free compressors have fewer moving parts and fewer parts overall. There are fewer seals and bearings. This simplicity of design increases system robustness and decreases maintenance costs. Oil free compressors are smaller than traditional compressors; they weigh less and occupy less floor space.

 

Oil free compressors require less maintenance than traditional compressors. Traditional compressors need periodic oil changes and other maintenance.

 

All compressors use bearings and shafts. Oil free compressors typically use sealed bearings; that do not need lubrication or servicing. Some oil free compressors use oil for lubricating bearings and shafts—but this oil is not in contact with the air being compressed.

 

BOGE Australia Oil free Air Compressor

BOGE is celebrating 111 years of excellence.

 

BOGE Compressed Air Systems was founded in 1907, by Otto Boge in the city of Bielefeld Germany. The company is still family owned, and is in its fourth generation. High quality BOGE products are built in Bielefeld, and used in over 120 countries.

 

BOGE’s production of precision equipment and strong commitment of serving our international customers—has long been a success factor for the company, with numerous sales offices worldwide and a total of 13 subsidiary companies in locations including Australia, the USA, and India.

 

In 2014, BOGE opened another production facility—this time in Großenhain Germany—in order to service an increasing world-wide demand for BOGE products.

 

 

BOGE Australia has its headquarters in Pakenham Victoria (near Melbourne) with local sales and service partners all over Australia.

 

BOGE Compressors (Australia) Pty Ltd
49 National Avenue
PAKENHAM 3810 Victoria
Australia
Telephone: +61 03 5940 3266
Facsimile: +61 03 5940 9279
Email j.rohner@boge.com

 

BOGE Australia is a valuable resource to anyone building an air system. Whether you are installing a single compressor or designing an integrated, multi-building complex—let BOGE help.