Why Correctly Sizing Pneumatic Components is Important
The most important function in the design of a pneumatic system is to correctly size the pneumatic components. Too often, components are chosen primarily because of what is readily available at the time or because the component is already currently being used throughout a facility. Improperly sourced components can result in an inefficient system leading to decreased productivity and increased cycle times, along with increased component and energy costs associated with compressed air.
One of the key factors in determining how to properly size for performance and efficiency includes Actuator selection.
Actuator selection is the most critical aspect in designing a system. If the actuator is too large, all other components will need to be oversized to meet required cycled times and energy cost will increase. If the actuator is too small, the load will either move erratically or not at all. Sizing an actuator includes these key factors:
1) Determine the force in pounds required to move the load. Add 25% to provide enough power to overcome friction and move the load at less than 4 inches/second, add 50% to move the load at 4 to 16 inches/second, and/or add 100% to move the load at speeds above 16 inches/second.
2) Find out the minimum air pressure in pounds/square inch (PSI) that will be present to operate the actuator.
3) Divide the force by the pressure to determine the power factor required.
4) Choose the next largest power factor in the chart below to determine the bore size.
Example: Estimated force needed is 220 pounds and air pressure available is 80 PSI. Therefore, 220 ÷ 80 = 2.75 power factor. For this application and using the chart above, it’s then necessary to round up the power factor to 3.1 and have the bore size be 2”.
Optimizing performance, reducing component costs and reduced energy costs associated with compressed air are all easily achieved if time is taken to properly size out air components within the early planning stages of your design.
Click the link below for additional details and sizing charts to help guide you in taking the necessary steps to ensure a properly designed system.