For every dripper to deliver the same amount of water, enough water pressure must reach every point of the system. On its way through pipes, filters and fittings, however, pressure is lost – the pressure loss. Anyone who knows it and plans for it avoids weak end drippers and failures.
Where pressure loss comes from
- Friction in the pipe: increases with length and decreases with a larger diameter.
- Flow rate: the more water, the higher the friction loss.
- Height difference: 10 metres of height correspond to about 1 bar.
- Components: filters, valves and fittings cost additional pressure.
Rules of thumb for practice
| Parameter | Guide value |
|---|---|
| Operating pressure of drippers | 1–2 bar |
| Height difference | 10 m ≈ 1 bar |
| Flow velocity | preferably ≤ 1.5 m/s in the pipe |
| Pressure loss per zone | plan approx. 0.5 bar as a reserve |
How to avoid excessive pressure loss
The greatest leverage lies in the pipe diameter: a larger pipe lowers the velocity and thus the loss significantly. Further measures: split long runs into zones, clean the filter regularly and, if the inlet pressure is too high, set a pressure reducer to 1–2 bar.
Calculate it directly
Determine the right diameter for your flow rate here:
Measure the basis – the available flow rate – using the bucket method. The complete plan including a parts list is created by the irrigation planner.
Expert advice from KLN: Together we design the pressure, diameter and zones for your system. Send your enquiry now.