How to Select an Air Receiver Tank According to the Compressed Air System

The air receiver tank is an important component within a compressed air system. Different operating conditions require different types of air receiver tanks.
First, let us clarify one question: What functions does an air compressor air receiver tank perform in a compressed air system?
Store compressed air to satisfy sudden instantaneous peak air demand of consuming equipment;
Store compressed air and eliminate airflow pulsation inside pipelines;
Pre-cool compressed air and condense part of liquid water. Therefore, the air receiver tank needs regular draining;

Enable automatic start-stop control of the air compressor. Once the tank pressure reaches the set value, the compressor will shut down automatically, 

avoiding continuous operation and wasted electric energy.

Theoretically speaking, the larger the air receiver tank, the better, as it reduces frequent compressor startups. Star-delta starting is direct on-line startup; 

the instantaneous motor starting current reaches approximately 7 times the rated current. Frequent startup causes severe damage to the compressor electrical components, 

shortens their service life, and creates heavy impact on the power grid, interfering with the normal operation of other electrical equipment.

Variable frequency air compressors adopt soft start, with starting current roughly twice the rated current, so the impact is relatively minor.
This raises a question: Can a screw air compressor run without an air receiver tank?

The air receiver tank installed at the compressor outlet not only stabilizes discharge pressure and acts as a buffer, but also has another important function often overlooked by users: 

preventing liquid backflow from compressed air pipelines into the air compressor during shutdown, which would lead to unit damage. If the receiver tank is omitted, 

an inverted U-bend piping design must be adopted to achieve the same protection effect during pipeline layout.

Furthermore, the air receiver tank maintains pipeline pressure in the compressed air system and restrains drastic pressure fluctuations. 

Since air consumption at the end of the compressed air system generally cannot remain stable all the time, the receiver tank balances system pressure and reduces frequent loading and unloading cycles of the air compressor. 

Another function is to re-cool dried compressed air so as to lower the moisture content inside the air.

For certain special compressed air systems, such as large-displacement centrifugal air compressors with large-volume pipe networks (large-diameter, 

lengthy pipelines) and stable air consumption, operation without an air receiver tank is feasible. Nevertheless, most compressed air systems require an air receiver tank.

Air compressors have no internal space to store compressed air. Generated compressed air must be consumed immediately, which represents an unfavorable operating mode. 

With an air receiver tank, compressed air is first charged into the tank until the preset pressure is reached. The compressor restarts only when pressure drops to a defined level. 

This configuration is more ideal both from the perspective of energy utilization and compressed air quality. Hence, an air receiver tank is generally indispensable.

However, equipment with low and intermittent compressed air demand can operate without an air receiver tank. Still, for stable compressor performance, 

constant compressed air pressure and guaranteed air quality, installation of an air receiver tank is recommended.

Systematically speaking, equipping an air compressor with a properly sized air receiver tank brings the following benefits:
Stabilize Compressor Operation
Frequent startup and shutdown of pressure vessels intensifies valve wear and destabilizes both oil and air circuits, resulting in unstable machine operation. Installation of an air receiver tank effectively alleviates this situation.
Energy Saving Effect

Frequent startup and shutdown of the air compressor leads to high motor power consumption. If the compressor stays in the no-load state for a long period, 

substantial energy will be wasted. In an air system equipped with an air receiver tank, the compressor can maintain stable operation, reducing unnecessary energy loss caused by idling.

Supply Stable Air Source

Why should an air compressor be matched with an air receiver tank? When an air receiver tank is incorporated into the compressor system, it serves as a buffer for discharged air, 

maintaining air pressure around the set value and delivering constant pressure to air-consuming systems — an essential requirement for modern factory operation.

Improved Compressed Air Quality

Compressed air exiting the air compressor first enters the air receiver tank and remains resident for a certain time. Impurities, moisture and other contaminants inside the air can settle, 

and the temperature of compressed air decreases. Even without a refrigerated air dryer, relatively high-quality compressed air can be supplied.

Simply put, the air receiver tank works in the same way as a reservoir. The air compressor acts as the air source, and the air receiver tank acts as the storage pond. 

The receiver tank stabilizes pressure within a specified range as configured, buffers pressure fluctuations, reduces compressor startup frequency, and functions to settle impurities and moisture carried in compressed air.