Scuba tanks are an essential part of every scuba diver’s kit. Although they don't contain air, they have a lot of gas. This is usually more than what they can hold. There are many sizes that can be used for different types of diving. It is important to pick the right tank according to what kind of water you will be using. Below are the main types and sizes of scuba tanks.
scuba tanks contain no air
Standard aluminum 80 cylinders can hold 77 cubic feet of air. Trimix, a dive gas, is 10-20% smaller than air. Also, higher maximum service pressures don't necessarily equal more air. Although manufacturers overestimate the tank's capacity, they often do so. It is therefore important to check the capacity of each individual cylinder against the actual volume.
They are able to store more free gas than they can hold in water.
Technical divers use a different mix of gases than recreational divers. As such, their true air or Trimix capacities are lower than their actual waters capacities. Helium, which is more compressible and less elastic than air, means that their true air or Trimix capacities will be smaller than their water capabilities. The true air volume of Double HP117 cylinders is 235 ft3, while Heliair 10/50 cylinders have a true capacity of 216 Ft3. You can use the Z Factors of SCUBA tables to determine the correct mixed gases capacity.
They are made of steel or aluminum
When choosing between a steel and an aluminum scuba tank, consider which is more suitable for a divers' needs. Steel tanks are more durable and can withstand deeper dives. This durability comes at a price. Aluminum tanks are more susceptible to structural fractures and can prove dangerous. A steel tank costs more that an aluminum one. However, aluminum tanks have become the industry standard.
They are available at different sizes
Scuba tanks can be made from two materials: aluminum or steel. Steel tanks tend to be lighter and more durable than aluminum, but they are heavier. An aluminum tank may be better if you plan to dive frequently and need to carry a weight belt. Aluminum tanks are lighter than steel tanks. You will need to consider your weight requirements when purchasing an aluminum tank. Steel tanks can be used for local and drysuit diving.
They must be inspected often
There are many ways you can check your scuba tank. Hydrostatic testing usually is done below the tank's neck. A visual inspection can also help you find corrosion or contamination. Tumbling is another way to check the condition of your tank. Tumbling involves filling your tank with media, and then spinning it for a period of time to remove any dirt or other contaminants. If the tank sounds rattly, it may mean it needs to be cleaned.