Understanding the Role of Air Receivers: 

Air Receivers act as buffer tanks that store compressed air, allowing for smooth and consistent delivery to downstream equipment. They help minimise pressure variations within the system, which can result from fluctuations in demand or the cyclic operation of compressors. By providing a reserve of compressed air, receivers enable compressors to operate more efficiently by reducing the frequency of starts and stops, known as cycling. 

Factors Influencing Air Receiver Sizing: 

1. Compressor Capacity: The size and output capacity of compressors supplying the system determine the rate at which compressed air is generated. A larger compressor or a bank of compressors will require a larger air receiver to accommodate the compressed air. 

2. Air Demand Profile: It is crucial to analyse the demand profile of your compressed air system. Factors such as peak usage periods, average demand, and intermittent or cyclical demands should be considered. This analysis helps determine the necessary storage capacity of the air receiver to meet fluctuating demand while maintaining pressure levels. 

3. Pressure Drop Tolerance: Pressure drop across the system, including piping and downstream equipment, must be considered. The air receiver should be sized to compensate for pressure losses and ensure an adequate compressed air supply is available at the required pressure. 

4. Compressor Cycling Rate: Minimising the frequency of compressor starts and stops improves energy efficiency and prolongs equipment life. A properly sized air receiver can help reduce compressor cycling by providing a buffer of stored air to meet short-term demand spikes. 

Calculating Air Receiver Capacity: 

Here is a primary method for determining the appropriate size of an air receiver: 

1. Determine Required Air Volume: Calculate the total air volume required to meet peak demand during the specified period (e.g. one minute). This can be estimated based on your equipment's maximum flow rate and peak demand duration. 

2. Account for Pressure Fluctuation: Consider the desired pressure range within which the compressed air system should operate—factor in pressure drop allowances to ensure that the Receiver maintains adequate pressure levels during peak demand. 

3. Calculate Receiver Size: Use the formula below to calculate the minimum required volume for the air receiver: 

V=P1​−P2​Q×(T2​−T1​)​

Where:

V = Receiver volume (cubic feet or cubic meters)

Q = Total air flow rate (cubic feet per minute or cubic meters per minute)

T1​ = Initial pressure (psig or bar)

T2​ = Final pressure (psig or bar)

P1​ = Initial pressure (psig or bar)

P2​ = Final pressure (psig or bar)

1. Select Receiver Size: Choose an air receiver with a volume equal to or slightly larger than the calculated value to ensure sufficient capacity.

Conclusion: 

To get the most out of compressed air systems, it's crucial to size the air receivers correctly. By considering factors such as compressor capacity, demand profile, pressure fluctuations, and cycling rates, engineers can select the right air receiver size to meet their specific application's needs. Spending effort to properly size air receivers can result in substantial savings on energy, decreased maintenance expenses, and enhanced system dependability, ultimately contributing to industrial operations' overall productivity and profitability.