PIPE SIZE CALCULATOR
What size pipe do I need?
Enter how much water you need to move and how far. We'll show the pipe size that keeps the water at a sensible speed, the pressure you'll lose on the way, and the class to order.
1 · FLOW
m³/h2 · LENGTH OF THE LINE
m3 · HEIGHT TO LIFT THE WATER
mFrom the pump (or water level) up to the highest outlet. Use 0 for a level line.
4 · PIPE
RECOMMENDED SIZE
110 mm
- WATER SPEED
- –
- PRESSURE LOST IN THE PIPE
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- TOTAL HEAD AT THE PUMP
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- CLASS CHECK
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EVERY SIZE AT THIS FLOW
Tap a size to see it in the pipe above.
| SIZE | BORE ≈ | WATER SPEED | LOSS PER 100 m | LOSS OVER THE LINE |
|---|
HOW IT WORKS
Speed first, then pressure
Keep the water between 0.5 and 1.5 m/s
Slower than that and you're paying for more pipe than you need. Faster and you lose more pressure, wear the pump harder and get bigger pressure surges. We recommend the smallest size that stays at or under 1.5 m/s and loses no more than 3 m of pressure per 100 m.
Friction eats pressure
Water rubbing on the pipe wall loses pressure along the line. We use the Hazen-Williams formula with C = 150 for smooth new PVC and PE pipe, and the bore from the minimum wall.
Lift plus friction is your pump head
Height to lift plus the friction loss gives the head at the pump, and that sets the pressure class. Add 10 to 20% for bends, valves and fittings, and a margin for surge.
A planning guide for clean water at about 20 °C, not a design. Your engineer's figures come first, and we're happy to check a line for you: send the flow, length, height and the pump you plan to use.
Want us to check the size?
Send the flow, the length, the height and the pump. Send your request early in the day and we'll quote the same working day.