1. Storage: The primary function of an air storage tank is to store compressed air. This storage capability allows the system to meet short-term peak air demands that the compressor alone cannot handle.
2. Pressure Stabilisation: A compressed air vessel helps stabilise the pressure in the system. It acts as a buffer, reducing the impact of pressure fluctuations caused by varying demand.
3. Moisture Removal: Moisture can collect inside a compressed air container, especially in systems without an air dryer. The tank helps in removing this moisture, preventing corrosion and damage to pneumatic equipment.
4. Energy Efficiency: By allowing the compressor to operate on a longer cycle and lower pressure bands, an air tank contributes to reducing energy consumption and extending the compressor's life.

Air storage containers come in various types and configurations, each suited for different applications and requirements. The most common types include:

1. Vertical Storage Tanks: These are the most common type and are often used in applications where space is limited. They are designed to stand upright and are available in various sizes.
2. Horizontal Storage Tanks: These are designed to lie horizontally and are typically used in applications where height is a constraint. They are also available in various sizes.
3. Tank-Mounted Compressors: Some air compressors come as a package and are mounted on top of the storage tank. These are known as tank-mounted compressors and are commonly used in smaller applications.

A compressed air vessel is an essential component of a compressed air system for several reasons:

1. Minimising Pressure Fluctuations: An air storage tank helps in minimising unstable peaks in compressed air pressure, ensuring a stable supply of compressed air even when demand changes throughout the day.
2. Reducing Compressor Load: By providing a reserve of compressed air, an air tank reduces the loading and unloading cycles on the compressor, making it work more efficiently and extending its lifespan.
3. Improving Efficiency: A compressed air vessel can help improve the efficiency of an air dryer if placed before the dryer. It removes excess moisture from compressed air before it enters the air dryer, enhancing its performance.
4. Safety: In an emergency, a compressed air storage container can help improve process safety by providing a supply of air that allows production processes and systems to be safely shut down.