How to choose the air volume of air compressor

Choosing the right air compressor volume requires comprehensive consideration gas demand, equipment characteristics and environmental factors and other factors. The following is a detailed selection guide:

1. Key Considerations

1. gas Demand Analysis
   • statistics of total gas consumption: List the rated gas consumption of all gas-consuming equipment (e. g., pneumatic tools, production line equipment) and consider peak gas consumption (e. g., during peak production hours).
   • Reserved allowance: It is recommended that the gas balance should be at least 10%-20%. If the gas end is far away from the air compressor or there is a production expansion plan, the balance can be increased to 20%-30%.
   • Formula Reference:
     required gas volume = total gas volume × 1.1~1.2 (coefficient)
     (For example, if the total gas consumption is 20m & sup3;/min, the recommended gas selection is 22-24m & sup3;/min)
2. device characteristic matching
   • pressure demand: Select the pressure level according to the equipment requirements (such as 7bar, 8bar), and consider the pipeline pressure loss (recommended pressure margin 1-2bar).
   • Air compressor type:
     • piston type: Suitable for small displacement and low pressure scenarios (such as maintenance workshops).
     • screw type: Cost-effective, suitable for most industrial scenarios (such as manufacturing).
     • Centrifugal: Suitable for continuous operation with large displacement (such as chemical plants).
   • Energy efficiency grade first-class energy efficiency (specific power ≤ 7.2kW/(m & sup3;/min)) is preferred, and the energy saving effect is remarkable.
3. Environmental Impact Assessment
   • temperature: High temperature resistant models shall be selected or cooling measures shall be added in high temperature environment.
   • Humidity: High humidity areas need to strengthen the drying of air compressor.
   • Elevation: The air in high altitude areas is thin, and the air volume parameters need to be corrected.

2. selection steps

1. calculate total gas consumption
   • instrumental statistical method: Summarize the air consumption of all gas-consuming equipment (refer to equipment nameplate or supplier data).
   • measurement method: When the production line is running, use a flowmeter to measure the actual gas consumption of key nodes.
2. Select air compressor type and specification
   • small displacement (<10m & sup3;/min): Piston or small screw machines are preferred.
   • Medium displacement (10-50m & sup3;/min): Select screw type air compressor, and select frequency conversion or power frequency according to the fluctuation of gas consumption.
   • Large displacement (>50m & sup3;/min): Select centrifugal or multiple screw machines in parallel.
3. Determine pressure and power
   • pressure: Terminal pressure + pipeline loss (usually plus 1-2bar margin).
   • Power: Choose the matching motor power according to the air volume and pressure, and avoid "big horse-drawn cart" or "small horse-drawn cart".

3. selection recommendations

1. avoid Common Mistakes
   • blind selection of large models: Excessive air compressor will frequently load and unload, resulting in increased energy consumption and oil emulsification.
   • Neglect the alternative: It is recommended to configure spare air compressors for key production lines to prevent shutdown due to single failure.
2. Optimize gas allocation
   • multiple joint control: For scenes with large air consumption fluctuations, power frequency + frequency conversion air compressor can be combined to give consideration to efficiency and adjustment flexibility.
   • intelligent control: Adjust the gas volume in real time through the Internet of Things monitoring system to avoid energy waste.
3. Consulting Professionals
   • provide detailed gas consumption data (such as equipment list and gas consumption curve) to air compressor manufacturers to obtain customized solutions.
   • Consider full life cycle costs (including energy consumption, maintenance, accessories, etc.).

4. example calculations

scene: The filling line of a food factory needs to drive 10 pneumatic filling machines, each with a rated gas consumption of 2m & sup3;/min, the peak gas consumption is 1.5 times of the total gas consumption, and the pressure requirement is 7bar.
Calculation:

1. total gas consumption= 10 units × 2m & sup3;/min = 20m & sup3;/min
2. peak gas consumption= 20m&sup3;/min × 1.5 = 30m&sup3;/min
3. type selection gas volume= 30m & sup3;/min × 1.2 (margin) = 36m & sup3;/min
4. pressure selection= 7bar + 1bar (margin) = 8bar
   recommended Scheme: Select 2 sets of 20m & sup3;/min screw air compressor (one for use and one for standby), or one 37m & sup3;/min frequency conversion screw machine.

Summary: Air compressor capacity selection needs to be "tailored" to balance current needs and future expansion, combined with professional advice to ensure the accuracy and economy of selection.