Incorrect selection of hose diameter is one of the most common mistakes made when building and modernizing hydraulic systems. A hose that is too narrow causes a sharp increase in flow velocity, leading to turbulence, drastic oil heating, and significant pressure losses.
With our calculator, you can select the optimal internal hose diameter in seconds.Hydraulic Hose Diameter Calculator
Calculate the optimal internal hose diameter based on flow rate and line type.
Why is the internal hose diameter crucial?
In power hydraulics, it is not the external hose diameter that matters, but its internal cross-section (DN). It determines whether the oil will flow freely (laminar flow) or start to generate resistance (turbulent flow).
Using too small a diameter results in:
-
System overheating: Friction of oil against the walls of an overly narrow hose converts pressure energy into heat.
-
Cavitation: Especially dangerous in suction lines – an overly narrow hose can destroy a hydraulic pump in minutes.
-
Power loss: Instead of powering the cylinder, energy is "wasted" overcoming hose resistance.
Recommended Flow Velocities
For the system to operate efficiently and reliably, the oil velocity should fall within specific ranges, depending on the hose function:
-
Suction lines (pump supply): 0.5 – 1.2 m/s (the most critical section!)
-
Return lines (to tank): 2.0 – 4.5 m/s
-
Pressure lines (working): 3.0 – 7.5 m/s
Our calculator automatically adopts safe, averaged values for each of these types to facilitate quick selection.
How to calculate it yourself? (Formula)
If you want to perform calculations manually, use the following formula for internal diameter:
d = √ [ (4000 * Q) / (60 * π * v) ]
Where:
-
d– internal hose diameter (mm)
-
Q– flow rate (L/min)
-
v– fluid velocity (m/s)
Complete your system with BRhydraulic
Once you know the required diameter, it's time to select the appropriate components. In BRhydraulic's offer, you will find everything necessary for a professional hydraulic system:
-
Solenoid valves: Ensure precise control of oil direction and flow in your system.
-
Cylinders: A wide selection of ready-to-use cylinders with various strokes and diameters, ready for operation in the toughest conditions.
- CETOP blocks: Modular connection plates and blocks facilitating the construction of compact and efficient hydraulic systems.
Need help with a custom project? Our specialists will help you choose not only hoses but also the entire hydraulic control system!
