Hydraulic Cylinder Speed Calculator
Calculate the extension and retraction speeds of your hydraulic cylinder based on flow rate and piston dimensions
Calculation Results
Calculation Formula
The hydraulic cylinder speed is calculated using the following formulas:
Extension Speed (in/min) = (Flow Rate (GPM) × 231) / Piston Area (in²)
Retraction Speed (in/min) = (Flow Rate (GPM) × 231) / Annular Area (in²)
Piston Area = π × (Bore Diameter/2)²
Rod Area = π × (Rod Diameter/2)²
Annular Area = Piston Area – Rod Area
For metric units, the formulas are adjusted accordingly with LPM and mm measurements.
Frequently Asked Questions
Hydraulic cylinder speed refers to the rate at which the piston rod extends or retracts, typically measured in inches per minute (in/min) or millimeters per second (mm/s). It depends on the flow rate of hydraulic fluid into the cylinder and the piston area.
Retraction is typically faster because the annular area (piston area minus rod area) is smaller than the full piston area. With the same flow rate, the fluid has less space to fill during retraction, resulting in higher speed.
System efficiency accounts for factors like internal leakage, friction, and other losses. A lower efficiency percentage means the actual speed will be less than the theoretical calculation. Most systems operate between 85-95% efficiency.
For double-rod cylinders where the rod extends through both ends of the cylinder, the extension and retraction speeds will be equal because the annular area is the same in both directions. Simply enter the same rod diameter for both sides.