“Scuba Diving Made Safer With Oil Free Air Compressor Technology”
For recreation, and sometimes research, scuba diving is surely a fun activity to practice. Although it is not a professional sport, there are several professions that depend on it. For instance, companies that supply compressed air for underwater breathing depend on the number and frequency of divers descending below the water surface.
Since we’ve come up to the topic, it’s reasonable to know that breathing underwater is something that humans are incapable of by nature. However, with the advancement in technology and a lot of practice we’ve developed ourselves a few methods that help us stay below the surface of the water for several hours. And this article will shed light on one such technology- air compressors.
What is an Air Compressor?
As the name suggests, an air compressor is a machine that packs a lot of air inside a smaller container. Well, there are several types of compressors including reciprocating, rotary, and tornado type compressors, about which more info is available online. Besides, there are two other categories that further separates these compressors from each other- oiled and oil-free.
The air compressors that are used in diving need to be free from any type of toxic contaminants. Apart from this, maintaining a constant air pressure is another prerequisite for these compressors. Using an oil-free rotary air compressor solves both of these problems. Absence of oil helps keep the air clean, and rotary compression, or as it is commonly known as a screw compression, is helpful in maintaining the pressure constant.
But still, this does not explain why to use an air compressor at all!
Why Use Air Compressors with Diving?
As a diver descends below the surface of the water, the pressure starts increasing. The rising pressure tries to push the air out of the lungs and veins of the divers. This is the first reason why an air compressor is used. The compressor helps keep a balance between the external and internal pressure in the divers’ body.
Secondly, reducing air density with the increasing depth in the ocean waters makes it difficult to supply air through direct lines. Using a compressor increases the pressure on the air and helps push it downwards as the diver descends. This brings us to possible ways of using an air compressor for supplying air to the divers.
Two methods are primarily used to deliver the air from the compressor to the divers. One, by storing the air inside a cylinder, which can then be carried by the diver when descending. And, second, by hooking a direct supply of air to the diver from the surface. When the compressed air is filled in the cylinders it is usually stored at very high pressure (somewhere between 200 to 300 bar). On the other hand, when the compressed air is delivered to the diver directly from the surface, it is usually kept at a lower pressure (below 150 bar). It helps maintain the critical balance between internal and external body pressures and also avoid decompression sickness.
Other Necessary Precautions Needed
When compressing the air for scuba divers, there are some precautionary measures that need to be taken. In this section, some of these precautions are discussed in detail.
Maintaining The Air Quality
Most importantly, the air used by scuba divers needs to be fit for breathing. In other words, the air should be free from toxic gases like carbon monoxide, carbon dioxide, and other contaminants. Carbon monoxide can be lethal in small traces, as it binds with the hemoglobin and reduces the blood’s capacity to carry oxygen. For this purpose, an air filter is used to remove all these harmful components whether filling the oxygen cylinders or supplying the air directly. Consequently, the filtration process also depends on the pressure of the air.
Pressure Of The Air Supplied
When the air is supplied directly from the surface using a continuous compressor, the pressure is usually kept below 150 bars, as already mentioned. This impacts the filtration process as well. Usually, composite air filters that can work efficiently at lower pressures are attached to the supply line between the compressor unit and the diver. On the other hand, when filtering air at high pressure for filling the oxygen cylinders, the filters are subjected to high forces. High pressure can damage the lining of the air filter. Therefore, air filters that allow easy flow through tiny pores are used when filling the cylinders. Besides, air filters for filling oxygen cylinders also need to be replaced frequently as compared to direct supply.
Thermal Balance Of The Compressor
Keeping equipment safe to carry at all times is also important. Filling the cylinders, particularly, causes the compressed air to heat up because of the adiabatic heating. However, the air slowly cools down as the heat is dissipated after the filling process is complete. A careful balance between the volume and the pressure needs to be maintained when filling the cylinders to avoid any accidents underwater. Usually, the cylinders are filled at a pressure that is suitable for operation at temperatures between 150 to 200 celsius, under normal conditions.
Blending The Oxygen With Other Gases
Using pure oxygen can be far more lethal than using air. The reason for this is that pure oxygen increases the body pressure underwater. So, when the diver ascends to the surface they may experience severe cramping in muscles as a result of declining external pressure. Therefore, the air is usually blended with other gases, mostly with nitrogen. This allows the divers to breathe underwater and experience mild pain in the muscles as they ascend. Another gas which is usually mixed with the air is water vapor. Moist air helps prevent dehydration when the divers are underwater.
Note: For filling the cylinders moisture content in the air is kept to a minimum because it can lead to rusting of the cylinders from inside. It could result in contamination of the air, and even failure of the equipment during its use.
Compression machinery is proving to be the one-stop solution for breathing problems that scuba divers face. In addition to this, using auxiliary equipment such as an air filter and a pressure monitor is also making scuba diving a safer sport.