Scuba tanks make up a fundamental part of any 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. The tank size will vary depending on what type of diving you do. You'll need to select the right tank based upon the water type you intend to use. Here are the main types of Scuba Tanks and their sizes.
scuba tanks contain no air
The standard aluminum 80 cylinder has a capacity of 77 ft3 of air. Trimix, a type of dive gas, has a ten to twenty-percent lower capacity than air. A higher maximum service pressure does not necessarily mean more air. However, manufacturers tend to exaggerate the tanks' capacities. You should therefore compare the capacity of each cylindrical against the actual volume.
They have a greater volume of free gas than their water capacity
Technical divers divers use different mix gases to divers than recreational divers. Therefore, their true air- and Trimix capacity is less than their water capacities. For example, Helium is more compressible than air so their true air and trimix capacities are lower than their water capacities. The true air volume of Double HP117 cylinders is 235 ft3, while Heliair 10/50 cylinders have a true capacity of 216 Ft3. Use the Z Factors to determine the correct mixed gas capability.
They can be made from 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 diving. But, durability comes at a cost. Aluminum tanks can develop structural fractures more quickly and can be dangerous. A steel tank is more expensive than an aluminum tank. But aluminum tanks are now the industry standard.
They come in a variety of 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 is better if you are planning to do a lot more diving and bring a weight belt. However, aluminum tanks are not as lightweight as steel tanks, so you should be aware of your weight requirements before purchasing one. Steel tanks work well for drysuit and local diving.
They need to be inspected on a regular basis
There are many ways to inspect your scuba tank. Hydrostatic testing is typically done by stamping into the tank's neck. An inspection visually can help you detect corrosion or contamination. Tumbling is another way of checking the tank's condition. Tumbling involves filling the tank in with media and spinning the tank for a specified period to remove dirt and contaminants. It may be necessary to clean the tank if it sounds rough.