In today’s world of pneumatics, air compressors remain vital to the operations of factories as well as workshops all across the globe. However, that has not always been the case because, in the context of the machine-age history, they are a recent invention.
Before the air compressors, a lot of the tools got the power from a variety of complicated systems with wheels, belts, as well as other large components. Such machinery was heavy, massive, as well as costly, and usually out of reach for a lot of small operations.
Nowadays, air compressors come in a variety of sizes and shapes, and it is easy to find them in auto workshops, shop floors, as well as in the garage of your neighbor. But do you know how air compressors work? That’s exactly what we will be explaining in this article, so keep on reading to find out.
You can also read how to operate an air compressor.
How Does Air Compressor Work – The Mechanics Of The Air Compressor
How they work may vary depending on a specific design. Piston-based air compressors usually have one of two kinds of compression cycles:
- Single-stage – Piston can compress the air in just one stroke. The stroke is a single full rotation of a crankshaft driving piston. A very simple, single-stage design can make a lot of these compressors perfect for private projects.
- Two-stage – The first piston starts compressing the air before directing it to the smaller cylinder, where the other piston keeps compressing it further. This design helps the compressor in generating higher pressures. Since the kinetic energy, which compresses air, can generate heat, a lot of two-stage systems can cool air as the air travels between every cylinder. Cooling the air helps the compressor in moving more air without any overheating.
Pumps vs. Compressors: The Instruments To Harness Air
A certain degree of confusion often exists between the two words “compressor” and “pump,” with a lot of people believing that they are one and the same. But in reality, a distinction between these two is the crucial part when it comes to discussing air compressors:
- The pump takes the gases or liquids and then moves them between the places.
- The compressor takes the gas, then squeezes it down to a much smaller volume as well as higher pressure, sending it elsewhere.
The most important distinction is that the pump may work with the liquids while the compressor cannot. The liquids are relatively harder to compress. The part which performs compression is the pump and one can find the pump within the compressor (in the reciprocating air compressor). Functions of compressors and pumps may overlap on the machines where pressure rises with every revolution.
For example, the tire pump can perform both tasks – it moves air and reduces its volume. Its purpose is to keep moving the outside air someplace else, into the air-tight space of a tire. Since the goal of it is not reducing the volume, technically it can not be considered the compressor.
The alternative example can be using pneumatic tools as well, which need compressed air. A device that reduces the volume of air is the compressor.
The air pumps typically fall into one of the two categories:
- The reciprocating pumps move back and forth. The bicycle pump is the reciprocating pump where a cylinder pulls the outside air in with the back-and-forth motion, moving it into the tire.
- The rotary pumps or otherwise known as the centrifugal pumps that spin. The rotary pump uses the impeller that is the enclosed propeller. It comes with the blades which move incoming fluid, later sending it through the outlet at high speed. Such a pump uses the motorized energy for pulling fluids from one specific place to the other, and it should not be confused with the turbine that captures fluids that are already moving.
How The Lubrication In Air Compressors Work: Oil-Free vs. Oil-Flooded
One of the most crucially important things you need to know is how the lubrication works. While looking at the oil pumps, you are dealing with the two categories:
- Oil-free pumps: The oil-free pumps typically receive special lasting lubrication which eliminates a need for oil. In a lot of industries where contamination can’t be the option, such as breweries, pharmaceutical manufacturing as well as food production, oil-free pumps remain a perfect option. They can ensure that oil does not contaminate the air they use in the product or process.
- Oil-lubricated pumps: In such design, the oil splashes onto the walls and bearings within a cylinder. This method is otherwise known as the oil-flooded lubrication and it tends to be much more durable. The piston ring is the piece of metal on a piston that helps in creating a seal inside a combustion chamber. This ring may help to keep the oil out of compressed air, but at times, it may still seep into a tank.
Oil-flooded pumps remain somewhat of the mixed bag. For the power tools which need lubrication, a presence of the oil in an airstream may be beneficial. Another important thing for the tools which require oil, the inline sources can distribute it in even amounts.
For woodworking and painting, oil may interrupt the whole process. It can keep the coatings from drying as well as finishing evenly. The airborne oil may even corrupt the surface of the wood projects. But fortunately, there are some tools that prevent oil from entering a tank, such as air-line filters as well as oil separators.
However, when the oil-free air remains critical to operation, then the oil-free compressors, as well as their permanent lubrication, remains the most optimal option.
Compressed Air In Our Everyday Life
From the pneumatic drills as well as braking systems to the HVAC units, the vast range of air-powered machines and tools ensure that our everyday life remains comfortable, efficient, and safe. In almost every building you pass by or walkthrough on the given day, the air tools helped someone to paint walls as well as plasterboards and hammer beams into place, and sand the wood.
On the shop floors all across the world, people actively use the compressed air for adding coats of paint as well as blast debris and dust away. It is indeed a remarkable thing that mankind discovered the ideal way to take the ambient air, the abundant resource on our planet, in order to transform it to power motorized equipment for a vast variety of purposes.