25 mm HDPE Pipe
Catalogue specifications for 25 mm polyethylene pipe.
Published
25 mm HDPE pipe means pipe with a 25 mm outside diameter. That figure alone does not define an order — at this diameter the factory produces 7 different pressure classes, which differ in wall thickness and therefore in bore, weight and price. What completes an order is the diameter plus the SDR and the material grade.
At 25 mm, wall thickness ranges from 1.5 to 4.2 mm and nominal pressure from 6 to 25 bar, depending on the SDR and on whether the material is PE80 or PE100.
Pressure classes available at this diameter
25 mm outside diameter — wall thickness by SDR
| SDR 21 | Wall thickness 1.5 mm — nominal pressure 6 bar in PE80, 8 bar in PE100 |
|---|---|
| SDR 17 | Wall thickness 1.8 mm — nominal pressure 8 bar in PE80, 10 bar in PE100 |
| SDR 13.6 | Wall thickness 2 mm — nominal pressure 10 bar in PE80, 12.5 bar in PE100 |
| SDR 11 | Wall thickness 2.3 mm — nominal pressure 12.5 bar in PE80, 16 bar in PE100 |
| SDR 9 | Wall thickness 3 mm — nominal pressure 16 bar in PE80, 20 bar in PE100 |
| SDR 7.4 | Wall thickness 3.5 mm — nominal pressure 20 bar in PE80, 25 bar in PE100 |
| SDR 6 | Wall thickness 4.2 mm — nominal pressure 25 bar in PE80 (the catalogue states no PE100 figure) |
Figures from the factory catalogue (DIN 8074 / ISO 4427-2). A lower SDR means a thicker wall, a higher pressure rating and a smaller bore.
The nominal pressure figure applies at 20 °C. If the line runs warmer, the real allowable pressure is lower and has to be calculated with the temperature derating factor.
Supply form
- SDR 13.6 (10 bar): coils of 200 m
- SDR 9, 7.4, 6 (16, 20, 25 bar): coils of 200 m
This diameter in gas networks
25 mm also appears in the catalogue's gas table: SDR 11 at a minimum wall of 3 mm, supplied in 100 m. Note that gas pipe is a separate product — produced to INSO 11223, with its own marking and approval and electrofusion jointing. Water supply pipe of the same diameter cannot be used in a gas network.
This diameter in irrigation
25 mm also appears in the catalogue's drip irrigation table (ISO 8779), in PE32 and PE40 grades at lower pressure classes. That is not the same product as pressure water pipe.
What to state when ordering
- Outside diameter: 25 mm
- SDR or nominal pressure — without it the enquiry cannot be priced
- Material grade: PE80 or PE100
- Application: water supply, gas, irrigation, sewerage or industrial
- Length, supply form and delivery destination
FAQ
- What wall thickness does 25 mm HDPE pipe have?
- It depends on the pressure class. At 25 mm the catalogue offers 7 classes, from SDR 21 at 1.5 mm to SDR 6 at 4.2 mm. Without an SDR, the wall thickness is undefined.
- What is the pressure rating of 25 mm pipe?
- From 6 to 25 bar, depending on the SDR and material grade. Those figures apply at 20 °C; above that they must be corrected with the temperature derating factor.
- Is 25 mm supplied in coils or straight lengths?
- In coils, which reduces the number of joints along the route.
- How is 25 mm HDPE pipe priced?
- By weight, not by the metre. Weight per metre follows from diameter, wall thickness and material density — which is why 25 mm costs differently in each SDR. Quote the diameter, SDR and quantity to get a current price.