The CFM (cubic feet per minute) is a metric used to measure the air compressor’s capabilities to move air. It shows the operator the volume of air an air compressor can move in cubic feet in a minute. The CFM is an essential consideration for many industries, as the required CFM for different tools can vary across industries.
Understanding the CFM requirements of your industrial application is crucial while purchasing an industrial air compressor. Purchasing the air compressor that can provide and maintain desired CFM ensures that the industrial processes are running smoothly.
An experienced air compressor distributor would consider your CFM requirements and offer you a reliable air compressor that meets your needs. Let us have a detailed look at what is CFM in air compressors, what factors affect your CFM requirements and learn how to calculate air compressor CFM.
A] What is CFM in Air Compressors?
Air compressor CFM is the volume of compressed air an air compressor can provide to the system in a minute at a given pressure. Pneumatic tools require a set amount of airflow to operate as intended, if the CFM is lower than desired, the tool will stop working until the compressed air is provided.
The air compressor’s CFM also depends on the PSI (pound per square inch). The main difference between the CFM and PSI of an air compressor is that CFM measures the volume of airflow of the compressor while PSI measures the force at which air comes out of the compressor. The CFM is generally measured at a specific PSI and if the PSI changes the CFM will change as well.
While purchasing industrial air compressors, you must understand your machine’s CFM requirements and make a purchase accordingly. Uninitiated buyers may not know the airflow capabilities of different air compressors; hence it is important to ask the distributor about the capabilities of different air compressor options. One of the common misconceptions is that a higher CFM means a better quality air compressor, in reality, CFM is just one of the many performance indicators of how air compressors operate.
You must choose the air compressor CFM based on your industrial requirements to ensure efficiency. For example, A rotary screw air compressor with a CFM rating of 125 CFM at 116 PSI, such a model, would be suitable for industrial applications where a continuous and high-volume air supply is required.
B] Factors Affecting CFM Requirements
1. Tool Requirements
- Type of Tool: Your CFM requirements are based on how much airflow your business tools need. If your pneumatic machinery needs constant airflow for an extended time, you might want to get a compressor with a higher CFM.
- Operating Pressure: If the equipment requires a higher pressure to function properly, the CFM should also be high.
2. Pressure Requirements
In an industrial setting, different equipment can need different pressure to operate as intended. If certain equipment needs higher pressure, the CFM can be increased to maintain a constant flow. On the other hand, if the equipment requires low pressure, a compressor with high CFM could unnecessarily drive up the cost.
3. Application Specifics
- Size and Complexity: Equipment used for larger and more complex applications like the automotive industry or construction needs a higher CFM to maintain the constant airflow demands.
- Air Volume Needs Certain industrial applications like bulk conveying, and materials handling may need a higher volume of compressed air to maintain the
4. Simultaneous Tool Usage
When purchasing an air compressor, you must be aware of how much equipment is to be powered by it and what are their CFM requirements. If the number of tools powered with a single air compressor is high, the CFM of that air compressor should also be higher.
5. Environmental Factors
Environmental factors like temperature, altitude and moisture can affect the efficiency of the air compressors. Extreme environmental conditions can impact the CFM needs and have to be maintained accordingly.
6. Safety Factors
Unexpected problems can arise in any industrial process, to maintain safety, it is advisable to keep the CFM above the minimum. Conversely, very high CFM can be difficult to manage and be a safety concern.
7. Future Expansion
An air compressor with low CFM can be inexpensive upfront; however, if you are planning to expand your business in a few years, you might want to consider purchasing a compressor that can accommodate your future CFM requirements.
C] How To Calculate CFM Of Compressor?
- Find Your Equipment’s CFM Requirements: Each machinery needs a specific amount of airflow to maintain its desired output. You need to find each tool’s individual CFM consumption for a specific time and pressure.
- Calculate The Total CFM Consumption: Find the sum of all your tools and equipment’s CFM.
- Consider The Duty Cycle: The duty cycle of an air compressor is the ratio/percentage of time the machine needs to be on and off. The optimum ratio for a compressor to work efficiently is to have an 80% load and 20% unload duty cycle.
- Additional Factors To Consider: The CFM requirement of your equipment can vary depending on the pressure requirements, ambient conditions, and system losses. You must add or reduce the amount from the sum CFM to get accurate results.
- Selecting The Compressor: Discuss your CFM requirements and calculations with your air compressor supplier. The supplier can help you determine the right compressor for your CFM needs.
- Future Prospects: It is advisable to opt for a bigger air compressor than you require to provide the required amount of airflow during times of emergency or when you expand your business.
D] Tips for Maximising CFM Efficiency
- Regular Maintenance: Regular maintenance can help the air compressor to maintain its efficiency and provide the same CFM at a given PSI.
- Proper Sizing: The CFM of an air compressor is directly proportional to its size. Consider your average as well as the highest CFM requirements to buy the appropriate compressor.
- Optimal Operating Pressure: High operating pressure can break down the equipment over time. Lowering the pressure below required can hinder efficiency. It is advisable to keep the compressor’s pressure right above the minimum requirement of the equipment.
- Efficient Piping: Use high-quality pipes to prevent loss of efficiency from pressure drops and energy losses.
- Proper Tool Usage: The tools powered by the compressor should be compatible with the compressor’s CFM rating.
- Load Management: If the compressor is powering multiple tools, it is essential to manage the load and avoid excess demand from the compressor. Sequencing and scheduling tool usage can help you achieve optimal CFM distribution.
- Consider Variable Speed Drives: Air compressors with variable speed drive technology (VSD) adjust the motor speed to meet the airflow demands. Reducing compressor usage at times of low demand can help save energy.
- Insulation and Ventilation: Proper insulation and ventilation in the pipes can reduce pressure loss, maintaining a high CFM efficiency.
- Training and Awareness: Having trained workers can reduce mistakes that lead to stoppage and frequent breakdowns. Training employees can help boost your compressor’s efficiency as well as longevity.
- Monitor and Analyze: It is essential to monitor and analyse the performance of air compressors to detect problems early and conduct required repairs to maintain efficiency.
Purchasing your air compressor from a reputed dealer ensures access to high-quality maintenance at regular intervals, as reputed dealers value customer satisfaction. Regular maintenance from the dealer can help to keep the compressor running in the best condition.