A Look At Different Oxygen Cylinder Sizes
Oxygen is a gas which can be stored in alternate ways: either frozen in a form of cryogenics or compressed and stored in differing oxygen cylinder sizes under several thousands of pounds of pressure. Because the oxygen is stored under such huge amounts of pressure, the oxygen cylinder sizes are not proportional to the volume of oxygen stored inside of them.
Oxygen Cylinder Sizes
Oxygen cylinder sizes or oxygen tank sizes, vary from a large steel oxygen cylinder through to a tiny cylinder that can be held in the palm of your hand. In order to allow for a visual example of how much gas can be stored in a cylinder, we will take for an example a generic M-6 cylinder that has tank sizes that can be compared to a litre cool drink bottle.
1. The '1 litre bottle' oxygen cylinders capacity is up to 164 litres of oxygen. That is 164 litres of oxygen that can be shoved and compressed into a bottle that is no larger than an average bottle of milk. The answer to how this is even possible is the application of increased pressure to the oxygen.
2. The first litre of oxygen that is decanted into the cylinder needs only 15 psi of pressure, an amount just slightly more than the atmospheric pressure around the cylinder.
3. Each litre to follow needs a little more pressure until finally, the last litre enters the cylinder under pressure of about 2,000 psi.
4. Oxygen is rarely held at pressures higher than 200 bar / 3000 psi due to the risks of fire triggered by high temperatures caused by adiabatic heating when the gas changes pressure when moving from one vessel to another.
Gas cylinder storage plays an important part in avoiding unnecessary compressed gas accidents.
Oxygen Tanks
Tanks as discussed above can be used for a variety of tasks. Oxygen tanks are storage vessels for oxygen that is either held under pressure in compressed gas cylinders or as liquid oxygen in a cryogenic storage tank. All equipment coming into contact with high pressure oxygen must be "oxygen clean" and "oxygen compatible" to reduce the risk of fire."Oxygen clean" means the removal of any substance that could act as a source of ignition. "Oxygen compatible" means that internal components must not burn readily or degrade easily in a high pressure oxygen environment.
The Tank Size
The oxygen gas comes in a variety of oxygen cylinder sizes or oxygen tank sizes. These cylinders are used to store gas for:
- Industrial processes including the manufacture of steel and monel
- Compressed gas welding equipment
- Propellant for rocket engines
- Breathing at altitude
- Oxygen first aid kits
- Gas blending for creating diving breathing mixes such as nitrox, trimix and heliox
- Open-circuit scuba sets - mainly used for accelerated decompression in technical diving and some types of diving re-breather: oxygen rebreathers and fully closed circuit rebreathers.
Oxygen cylinder sizes vary depending on their function and interestingly enough, while the popular visual of the scuba divers breathing cylinder is how many people visualize what an oxygen tank would look like, divers carry oxygen cylinders to breathe, because it would kill them and the vast majority of divers are actually breathing air or nitrox stored in a diving cylinder.
