Permissible oil speeds
Calculation of hydraulic cylinders
When the piston rod is moved, the fluid required for this, e.g. hydraulic oil, flows into the hydraulic cylinder or out again on the other side.
The flow speed of the fluid depends on the travel speed and the cross-sectional area of the supply lines, especially in the ports and screw connections. A high flow speed generates a higher pressure loss at the drive and thus a reduction in hydraulic efficiency. The flow speed should therefore be kept as low as possible.
The permissible oil speeds depend on the properties of the fluid. Recommendations for mineral oils can be found in the following table.
Pressure lines
| Nominal pressure | > 3 bar | < 25 bar | > 63 bar | > 160 bar | > 250 bar |
| Permissible oil speed | < 3 m/s | < 5 m/s | < 6 m/s | < 8 m/s | < 10 m/s |
Return lines
| Permissible oil speed | < 3 m/s |
Further calculation formulas for the design of hydraulic cylinders:
Calculation formulas for the design of hydraulic cylinders
Calculation of the buckling resistance of hydraulic cylinders
Buckling cases calculation - Mountings of piston rod and cylinder
Calculation of the sine movement of hydraulic cylinders and oscillation cylinders