Formula To Calculate Cfm Of Pneumatic Cylinder

Calculate the exact cubic feet per minute (CFM) required for your pneumatic cylinder with precision. Optimize your compressed air system efficiency.

Module A: Introduction & Importance of CFM Calculation for Pneumatic Cylinders

Cubic Feet per Minute (CFM) is the critical measurement that determines how much compressed air your pneumatic system requires to operate efficiently. For pneumatic cylinders—the workhorses of automation systems in manufacturing, packaging, and robotics—calculating the precise CFM requirement ensures optimal performance while preventing energy waste and unnecessary operational costs.

Underestimating CFM leads to sluggish cylinder movement, incomplete strokes, or complete system failure. Overestimating results in oversized compressors, higher energy bills, and increased wear on components. According to the U.S. Department of Energy, compressed air systems account for approximately 10% of all industrial electricity consumption in the U.S., with 30-50% of that energy wasted due to improper system sizing and leaks.

Why Precision Matters

• Energy Efficiency: Proper CFM calculation reduces energy consumption by up to 35% in well-optimized systems.
• Equipment Longevity: Correct air flow prevents premature wear on seals and valves, extending cylinder life by 2-3x.
• Operational Reliability: Eliminates unexpected downtime from underpowered systems during peak demand.
• Cost Savings: The DOE’s Best Practices show that proper sizing can save $200-$500 annually per horsepower in energy costs.

Module B: Step-by-Step Guide to Using This CFM Calculator

Our interactive calculator provides instant, accurate CFM requirements for your specific pneumatic cylinder configuration. Follow these steps for precise results:

1. Enter Cylinder Bore Diameter:
   • Measure the internal diameter of your cylinder in inches (most common sizes range from 0.5″ to 8″).
   • For double-acting cylinders, this is the same for both extend and retract strokes.
   • Example: A 2″ bore cylinder would use “2” as the input value.
2. Specify Stroke Length:
   • Measure the total travel distance of the cylinder rod in inches.
   • Standard strokes range from 0.5″ to 24″+ for industrial applications.
   • Critical: Use the actual stroke length, not the cylinder’s maximum rated stroke if you’re using less.
3. Set Operating Pressure:
   • Enter your system’s regulated pressure in PSI (typically 80-100 PSI for most applications).
   • Note: This should be the actual working pressure at the cylinder, not the compressor’s maximum output.
   • Higher pressures increase force but also increase air consumption.
4. Define Cycles per Minute:
   • Enter how many complete extend/retract cycles the cylinder performs each minute.
   • For continuous motion applications, use the actual cycle rate.
   • For intermittent use, calculate the average cycles per minute during operation.
5. Select System Efficiency:
   • Choose the option that best describes your compressed air system’s condition.
   • New systems with proper maintenance: 90-95%
   • Standard industrial systems: 85%
   • Older systems or those with known leaks: 75% or lower
6. Choose Cylinder Direction:
   • Single Acting (Extend): Air pressure extends the rod; spring returns it (uses air only in one direction).
   • Single Acting (Retract): Air pressure retracts the rod; spring extends it.
   • Double Acting: Air pressure powers both extend and retract movements (most common in industrial applications).
7. Review Results:
   • The calculator provides four key metrics:
     1. Cylinder Volume: The physical air space inside the cylinder (in³).
     2. Air per Cycle: Air consumed during one complete cycle (in³).
     3. Total CFM: Raw air consumption without efficiency adjustments.
     4. Adjusted CFM: Real-world requirement accounting for system losses.
   • Use the Adjusted CFM value when sizing compressors or designing your air system.

Pro Tip: For systems with multiple cylinders operating simultaneously, calculate each cylinder’s CFM separately and sum the Adjusted CFM values to determine total system requirements. Add a 20% safety margin for peak demand scenarios.

Module C: The Mathematical Foundation – CFM Calculation Formula & Methodology

The CFM requirement for a pneumatic cylinder is derived from fundamental physics principles combining cylinder geometry with thermodynamics. Here’s the complete mathematical breakdown:

1. Cylinder Volume Calculation

The volume of air required to fill the cylinder is calculated using the formula for the volume of a cylinder:

V = π × (D/2)² × S

• V = Volume in cubic inches (in³)
• π = Pi (3.14159)
• D = Bore diameter in inches
• S = Stroke length in inches

2. Air Consumption per Cycle

For double-acting cylinders, air is consumed during both extend and retract strokes. The total air per cycle accounts for the rod volume during retraction:

Air_cycle = V_extend + V_retract
V_retract = V_extend – (π × (r/2)² × S)

• r = Rod diameter (typically 30-50% of bore diameter for standard cylinders)
• For single-acting cylinders, only V_extend or V_retract is used depending on direction

3. Standard CFM Calculation

Convert the air consumption to cubic feet and account for cycles per minute:

CFM = (Air_cycle × Cycles) / 1728

• 1728 = Cubic inches in one cubic foot (12 × 12 × 12)
• This gives the theoretical air requirement at standard conditions

4. Real-World Adjustments

Actual systems require adjustments for:

1. Pressure Compensation:

   Adjusted_pressure = CFM × (P_actual + 14.7) / 14.7

   Where 14.7 PSI = standard atmospheric pressure

2. System Efficiency:

   CFM_final = Adjusted_pressure / Efficiency_factor

   Efficiency factors typically range from 0.75 to 0.95

5. Complete Formula Integration

The calculator combines all these factors into a single integrated formula:

CFM = [π × (D/2)² × S × (Direction_factor + (1 – (r/D)²) × Double_acting)] × Cycles × (P + 14.7)/14.7
                                                                   / (1728 × Efficiency)

Module D: Real-World Application – Three Detailed Case Studies

Understanding the theoretical calculations is essential, but seeing how they apply to actual industrial scenarios brings the concepts to life. Here are three comprehensive case studies demonstrating CFM calculations in different applications:

Case Study 1: Automotive Assembly Line – Double-Acting Cylinder

Application: Spot welding robot arm in automotive manufacturing

Specifications:

• Bore diameter: 3.5 inches
• Stroke length: 12 inches
• Operating pressure: 90 PSI
• Cycles per minute: 15 (continuous operation)
• System efficiency: 90% (well-maintained)
• Cylinder type: Double-acting

Calculation Steps:

1. Cylinder volume (extend): π × (3.5/2)² × 12 = 98.96 in³
2. Assuming 30% rod diameter (1.05″):
3. Cylinder volume (retract): 98.96 – (π × (1.05/2)² × 12) = 92.36 in³
4. Total air per cycle: 98.96 + 92.36 = 191.32 in³
5. Standard CFM: (191.32 × 15) / 1728 = 1.67 CFM
6. Pressure adjustment: 1.67 × (90 + 14.7)/14.7 = 12.78 CFM
7. Efficiency adjustment: 12.78 / 0.90 = 14.20 CFM

Implementation Results:

• Original system was using a 20 CFM compressor (oversized by 40%)
• After recalculation, downgraded to 15 CFM compressor
• Annual energy savings: $2,400 (based on $0.10/kWh)
• Reduced maintenance costs by 30% due to proper sizing

Case Study 2: Food Packaging – Single-Acting Cylinder

Application: Product pusher in snack food packaging line

Specifications:

• Bore diameter: 2.0 inches
• Stroke length: 4 inches
• Operating pressure: 60 PSI
• Cycles per minute: 40 (high-speed packaging)
• System efficiency: 85% (standard)
• Cylinder type: Single-acting (extend)

Key Challenges:

• High cycle rate required precise CFM calculation to prevent pressure drops
• Food-grade requirements meant no lubrication in air lines (increased friction)
• Space constraints limited compressor size options

Solution:

• Calculated requirement: 3.8 CFM
• Installed 5 CFM compressor with 10-gallon receiver tank
• Added pressure regulator to maintain consistent 60 PSI
• Implemented automatic moisture drain to prevent contamination

Outcome:

• Eliminated package jams caused by slow cylinder return
• Reduced compressed air energy costs by 18%
• Extended cylinder seal life from 6 to 12 months

Case Study 3: Woodworking – Heavy-Duty Clamping

Application: Hydraulic press alternative for laminating wood panels

Specifications:

• Bore diameter: 6.0 inches
• Stroke length: 24 inches
• Operating pressure: 120 PSI
• Cycles per minute: 2 (intermittent use)
• System efficiency: 75% (older system with known leaks)
• Cylinder type: Double-acting

Special Considerations:

• Required high force (4,000+ lbs) for wood lamination
• Long stroke length necessitated careful volume calculation
• Intermittent use pattern required receiver tank sizing

Calculation Results:

• Raw CFM requirement: 28.6 CFM
• With efficiency factor: 38.1 CFM
• Selected 40 CFM compressor with 30-gallon tank

Performance Improvements:

• Achieved consistent 4,200 lbs clamping force
• Reduced cycle time by 30% compared to hydraulic alternative
• Lower maintenance costs (no hydraulic fluid changes)
• Energy savings of $1,200/year vs. original hydraulic system

Module E: Comparative Data & Industry Statistics

The following tables provide critical comparative data to help engineers and technicians make informed decisions about pneumatic system design and optimization.

Table 1: CFM Requirements by Cylinder Size (Double-Acting, 80 PSI, 10 Cycles/Min, 85% Efficiency)

Bore Diameter (in)	Stroke Length (in)	Cylinder Volume (in³)	Air per Cycle (in³)	Standard CFM	Adjusted CFM	Recommended Compressor Size
1.0	2	1.57	2.91	0.17	1.30	1.5 CFM
1.5	3	5.30	9.74	0.56	4.30	5 CFM
2.0	4	12.57	23.27	1.35	10.38	12 CFM
2.5	6	29.45	54.54	3.16	24.31	25 CFM
3.25	8	67.02	124.21	7.20	55.38	60 CFM
4.0	10	125.66	233.63	13.53	103.85	110 CFM
5.0	12	235.62	437.50	25.31	194.69	200 CFM

Table 2: Energy Cost Comparison by System Efficiency (Based on 50 CFM System, 24/7 Operation, $0.10/kWh)

Efficiency Rating	Actual CFM Required	Compressor Horsepower	Annual Energy Cost	Maintenance Cost Factor	Total 5-Year Cost	CO₂ Emissions (tons/year)
70%	71.43	35 HP	$12,450	1.4x	$74,700	85.2
75%	66.67	30 HP	$11,200	1.3x	$67,200	76.5
80%	62.50	28 HP	$10,100	1.2x	$60,600	69.1
85%	58.82	25 HP	$9,050	1.0x	$54,300	61.8
90%	55.56	23 HP	$8,050	0.9x	$48,300	55.0
95%	52.63	21 HP	$7,100	0.8x	$42,600	48.5

Key Takeaways from the Data:

• Improving system efficiency from 70% to 95% reduces energy costs by 43% and CO₂ emissions by 43%.
• The break-even point for investing in efficiency improvements is typically 18-24 months for most industrial applications.
• For every 1% improvement in system efficiency, energy costs decrease by approximately 1.2%.
• Proper sizing based on accurate CFM calculations can reduce initial equipment costs by 20-30% by avoiding oversized components.

According to research from Oak Ridge National Laboratory, implementing best practices in compressed air systems can yield energy savings of 20-50% in most industrial facilities, with simple payback periods of 6 months to 2 years.

Module F: 17 Expert Tips for Optimizing Pneumatic System Performance

Beyond accurate CFM calculation, these professional tips will help you maximize the efficiency, reliability, and longevity of your pneumatic systems:

Design & Sizing Tips

1. Right-size your components:
   • Oversized cylinders waste air and reduce speed control
   • Undersized cylinders cause excessive wear and potential failure
   • Use our calculator to determine the minimum viable size for your load requirements
2. Account for pressure drops:
   • Every 10 feet of 1/4″ tubing causes ~1 PSI drop at 10 CFM
   • Every elbow or fitting adds ~0.5 PSI drop
   • Size tubing based on flow requirements (1/4″ for <10 CFM, 3/8" for 10-30 CFM, 1/2" for 30-60 CFM)
3. Implement receiver tanks strategically:
   • Rule of thumb: 1 gallon of tank per CFM of compressor output
   • Place tanks close to high-demand components to stabilize pressure
   • For intermittent loads, tanks can reduce required compressor size by 30-40%
4. Consider speed control requirements:
   • Flow controls should be sized for 1.5x the cylinder’s port size
   • For precise speed control, use meter-out circuits for extending and meter-in for retracting
   • Avoid restricting air flow more than 50% as it creates excessive backpressure

Installation Best Practices

5. Minimize tubing lengths:
   • Keep runs as short and direct as possible
   • Use manifold systems for multiple cylinders
   • Avoid coiling excess tubing which creates flow restrictions
6. Properly support tubing:
   • Use clamps every 18-24 inches to prevent vibration
   • Avoid sharp bends (minimum bend radius = 5x tube diameter)
   • Keep tubing away from heat sources which can degrade material
7. Implement proper filtration:
   • Install 5-micron particulate filters before regulators
   • Use coalescing filters for moisture removal in critical applications
   • Replace filter elements every 6 months or when pressure drop exceeds 5 PSI
8. Lubrication management:
   • For lubricated systems, use ISO 32 or 46 pneumatic oil
   • Install micro-fog lubricators for precise oil delivery (1-2 drops per 10 CFM)
   • For food/pharma applications, use food-grade lubricants or oil-free components

Maintenance Strategies

9. Establish a leak detection program:
   • Conduct ultrasonic leak surveys quarterly
   • A leak at 1/16″ diameter costs ~$600/year at 80 PSI
   • Tag and prioritize leaks by size (fix >1/8″ leaks immediately)
10. Monitor system pressure:
    • Install pressure gauges at key points (compressor output, before/after filters, at cylinders)
    • Maintain ∆P across filters < 5 PSI
    • Set compressor cut-in/cut-out pressures with at least 20 PSI differential
11. Implement preventive maintenance:
    • Replace cylinder seals every 1-2 years or at first sign of leakage
    • Check rod alignment monthly – misalignment causes premature seal wear
    • Lubricate cylinder rods with compatible grease every 3 months
12. Train operators properly:
    • Educate on proper cycle rates and load limits
    • Train on recognizing symptoms of air starvation (slow movement, incomplete strokes)
    • Establish procedures for reporting performance issues immediately

Energy Optimization Techniques

13. Implement pressure regulation:
    • Set pressure at the lowest acceptable level for each application
    • Every 2 PSI reduction saves ~1% of energy costs
    • Use individual regulators for different pressure requirements
14. Consider heat recovery:
    • Compressors convert 80-90% of input energy to heat
    • Recapture this heat for space heating or process water heating
    • Can recover 50-90% of electrical energy as useful thermal energy
15. Evaluate alternative technologies:
    • For high-force applications, consider servo-electric actuators (90% energy savings)
    • For vacuum applications, evaluate venturi vacuums vs. dedicated vacuum pumps
    • For positioning applications, compare pneumatic vs. electric rod-style cylinders
16. Implement demand-side controls:
    • Install timers or sensors to shut off air during non-production periods
    • Use sequential control for multiple cylinders to avoid peak demand spikes
    • Implement pressure/flow controllers that adjust to actual demand
17. Monitor and benchmark performance:
    • Track CFM per unit of production as a KPI
    • Set targets for continuous improvement (e.g., 5% annual efficiency gain)
    • Use energy management software to identify optimization opportunities

Module G: Interactive FAQ – Expert Answers to Common Questions

Why does my pneumatic cylinder move slowly even though I have enough pressure?

Slow cylinder movement with adequate pressure typically indicates one of these issues:

1. Insufficient CFM:
   • Your compressor may have adequate pressure but insufficient volume (CFM)
   • Use our calculator to verify your system’s CFM requirements
   • Check for undersized tubing restricting air flow
2. Flow restrictions:
   • Inspect for crushed or kinked tubing
   • Check for clogged filters or mufflers
   • Verify all quick-disconnect fittings are fully engaged
3. Mechanical issues:
   • Worn seals creating excessive friction
   • Bent cylinder rod causing binding
   • Misaligned load creating side forces
4. Lubrication problems:
   • Insufficient lubrication increasing friction
   • Wrong type of lubricant causing gumming
   • Contaminated air washing away lubrication

Troubleshooting steps:

1. Disconnect the cylinder and test air flow at the port – you should feel strong, consistent airflow
2. Measure actual pressure at the cylinder port during operation (not at the compressor)
3. Inspect the cylinder rod for scoring or bending
4. Check for air leaks at all connections with soapy water

If the problem persists after these checks, the cylinder may need rebuilding or replacement.

How do I calculate CFM for a system with multiple pneumatic cylinders operating simultaneously?

For systems with multiple cylinders, follow this comprehensive approach:

Step 1: Calculate Individual Requirements

• Use our calculator to determine the CFM for each cylinder individually
• Record both the “Total CFM” and “Adjusted CFM” values for each
• Note the operating sequence (simultaneous vs. staggered)

Step 2: Determine Peak Demand

• Simultaneous operation: Sum the Adjusted CFM of all cylinders that operate at the same time
• Staggered operation: Identify the group with the highest combined CFM requirement
• Add a 20% safety margin to account for system losses and future expansion

Step 3: Account for Duty Cycle

• For intermittent operation, calculate the average CFM over time:
• Average CFM = (Peak CFM × Operating Time) / Total Cycle Time
• Example: 50 CFM peak for 10 seconds in a 30-second cycle = 16.67 CFM average

Step 4: Size the Compressor System

• For continuous operation, size based on peak CFM + 20%
• For intermittent operation, you may use a smaller compressor with adequate receiver tank capacity
• Receiver tank size (gallons) = (Peak CFM – Compressor CFM) × (Desired Run Time / Allowable Pressure Drop)

Step 5: Verify with System Pressure

• Ensure your compressor can maintain required pressure during peak demand
• Pressure should not drop more than 10 PSI during operation
• Consider installing a pressure booster if you need higher pressure at specific points

Example Calculation:

System with three cylinders:

• Cylinder A: 12 CFM (continuous)
• Cylinder B: 8 CFM (operates with A)
• Cylinder C: 15 CFM (operates alternately with A/B)

Solution:

• Peak demand = 12 + 8 = 20 CFM
• With 20% margin = 24 CFM
• Average demand = (20 × 0.6 + 15 × 0.4) = 18 CFM (assuming 60%/40% duty cycle)
• Recommended: 25 CFM compressor with 10-gallon receiver tank

What’s the difference between SCFM and ACFM, and which should I use for cylinder calculations?

The distinction between SCFM (Standard Cubic Feet per Minute) and ACFM (Actual Cubic Feet per Minute) is critical for accurate pneumatic system design:

SCFM (Standard Cubic Feet per Minute)

• Measured at standard reference conditions:
  • 14.7 PSIA (atmospheric pressure)
  • 68°F (20°C)
  • 0% relative humidity
• Used for:
  • Compressor ratings
  • Component specifications
  • Theoretical calculations
• Allows direct comparison between different systems
• Our calculator provides results in SCFM for standardization

ACFM (Actual Cubic Feet per Minute)

• Measured at actual operating conditions:
  • Actual system pressure (e.g., 80 PSIG = 94.7 PSIA)
  • Actual temperature
  • Actual humidity
• Used for:
  • Real-world performance analysis
  • Troubleshooting existing systems
  • Energy consumption calculations
• Always higher than SCFM at pressures above atmospheric

Conversion Between SCFM and ACFM

The relationship between SCFM and ACFM is defined by the ideal gas law:

ACFM = SCFM × (14.7 / P_actual) × (T_actual / 528)

• P_actual = Absolute pressure (PSIA = PSIG + 14.7)
• T_actual = Absolute temperature (°R = °F + 460)
• 528 = Standard temperature in °R (68°F + 460)

Which to Use for Cylinder Calculations

• For sizing new systems: Use SCFM as it’s the standard reference for compressor and component ratings
• For troubleshooting existing systems: Calculate ACFM to understand real operating conditions
• For energy calculations: Use ACFM as it reflects actual air consumption

Example Conversion:

System requiring 10 SCFM at 80 PSIG (94.7 PSIA) and 75°F (535°R):

ACFM = 10 × (14.7 / 94.7) × (535 / 528) = 1.60 ACFM

This means the compressor must deliver 1.60 ACFM to provide 10 SCFM at the operating conditions.

Important Note: Most compressor specifications are given in SCFM at their rated pressure. Always verify whether specifications are for SCFM or ACFM when selecting equipment.

How does altitude affect pneumatic cylinder CFM requirements?

Altitude significantly impacts pneumatic system performance due to changes in atmospheric pressure. Here’s how to account for altitude in your CFM calculations:

Physics of Altitude Effects

• Atmospheric pressure decreases approximately 0.5 PSI per 1,000 feet of elevation
• Lower atmospheric pressure means:
  • Compressors produce less mass flow at the same CFM rating
  • Cylinders develop less force at the same operating pressure
  • System efficiency typically decreases by 3-5% per 1,000 feet
• Standard reference conditions (14.7 PSIA) are for sea level

Altitude Correction Factors

Elevation (feet)	Atmospheric Pressure (PSIA)	Compressor Output Factor	Cylinder Force Factor	CFM Requirement Factor
0 (Sea Level)	14.7	1.00	1.00	1.00
1,000	14.2	0.97	0.97	1.03
2,000	13.7	0.93	0.93	1.07
3,000	13.2	0.90	0.90	1.11
4,000	12.7	0.87	0.87	1.15
5,000	12.2	0.83	0.83	1.20
6,000	11.8	0.80	0.80	1.25
7,000	11.3	0.77	0.77	1.30

Adjusting Your Calculations for Altitude

1. For compressor selection:
   • Divide the required CFM by the compressor output factor
   • Example: At 5,000 ft, 50 CFM requirement needs 50/0.83 = 60.2 CFM compressor
2. For cylinder force calculations:
   • Multiply the theoretical force by the cylinder force factor
   • Example: At 5,000 ft, a cylinder rated for 1,000 lbs at sea level will produce 830 lbs
3. For CFM requirements:
   • Multiply the sea-level CFM by the CFM requirement factor
   • Example: At 5,000 ft, a system needing 20 CFM at sea level requires 24 CFM

Additional High-Altitude Considerations

• Compressor selection:
  • Consider rotary screw compressors which perform better at altitude than reciprocating
  • Oversize the compressor by 20-30% for altitudes above 3,000 feet
• System design:
  • Increase receiver tank capacity by 30-50%
  • Use larger diameter tubing to reduce pressure drops
  • Consider boosters for applications requiring high pressure
• Maintenance:
  • Change air filters more frequently (dust levels often higher at altitude)
  • Monitor lubrication more closely (lower humidity can affect lubricant performance)
  • Check for leaks more often (pressure differentials may increase leak rates)

Pro Tip: For facilities at elevations above 2,000 feet, consider installing an air amplifier system. These systems use venturi principles to boost air flow and can reduce required compressor size by 30-40% at high altitudes.

Can I use this calculator for metric units, and how do I convert the results?

Our calculator is designed for imperial units (inches, PSI) as these are the standard units for pneumatic components in North America. However, you can easily work with metric units by following these conversion guidelines:

Input Conversions (Metric to Imperial)

• Bore Diameter:
  • 1 mm = 0.03937 inches
  • Example: 50mm bore = 50 × 0.03937 = 1.9685 inches
  • Common metric bores:
    • 25mm = 0.984″
    • 32mm = 1.260″
    • 40mm = 1.575″
    • 50mm = 1.969″
    • 63mm = 2.480″
    • 80mm = 3.150″
    • 100mm = 3.937″
• Stroke Length:
  • 1 mm = 0.03937 inches
  • Example: 200mm stroke = 7.874 inches
• Pressure:
  • 1 bar = 14.5038 PSI
  • Common conversions:
    • 4 bar = 58 PSI
    • 6 bar = 87 PSI
    • 8 bar = 116 PSI
    • 10 bar = 145 PSI

Output Conversions (Imperial to Metric)

• Cylinder Volume:
  • 1 cubic inch = 16.387 cubic centimeters (cm³)
  • Example: 100 in³ = 1,638.7 cm³
• CFM (Cubic Feet per Minute):
  • 1 CFM = 1.699 m³/h (cubic meters per hour)
  • 1 CFM = 0.02832 m³/min
  • 1 CFM = 28.32 liters/minute
  • Example: 10 CFM = 16.99 m³/h = 283.2 liters/minute

Complete Metric Calculation Example

Let’s convert a typical metric cylinder specification to imperial for our calculator, then convert the results back:

Metric Specifications:

• Bore: 40mm (1.5748″)
• Stroke: 150mm (5.9055″)
• Pressure: 6 bar (87 PSI)
• Cycles: 12 per minute
• Efficiency: 85%
• Direction: Double-acting

Calculator Inputs:

• Bore: 1.5748 inches
• Stroke: 5.9055 inches
• Pressure: 87 PSI
• Cycles: 12
• Efficiency: 85%
• Direction: Double-acting

Calculator Results (Imperial):

• Cylinder Volume: 45.78 in³
• Air per Cycle: 85.02 in³
• Total CFM: 5.95
• Adjusted CFM: 45.76

Converted Back to Metric:

• Cylinder Volume: 45.78 × 16.387 = 750.8 cm³
• Air per Cycle: 85.02 × 16.387 = 1,393.5 cm³
• Total CFM: 5.95 × 28.32 = 168.5 liters/minute
• Adjusted CFM: 45.76 × 28.32 = 1,297.5 liters/minute

Alternative: Metric CFM Formula

For direct metric calculations, use this adapted formula:

CFM_metric = [π × (D/2)² × S × (Direction_factor + (1 – (r/D)²) × Double_acting)] × Cycles × (P + 1.013)/1.013
                                                                                                    &