PN6 is an internationally accepted pipeline pressure grade mark, representing a nominal pressure of 6 bar (0.6 MPa), which is the maximum working pressure that the pipeline can withstand for a long time at a water temperature of 20°C.
Material standard: in accordance with ISO 4427 or GB/T 13663 (PE80/PE100 raw materials)
Temperature correction: when the water temperature rises to 40°C, the maximum pressure resistance drops to about 0.4 MPa
Note: PN6 is associated with SDR (standard dimension ratio), and the common corresponding relationship is SDR17 (PE80) or SDR21 (PE100).
|
Parameter |
Typical Value (Example: DN110 Pipe) |
|
Outer Diameter |
110 mm (tolerance ±0.8 mm) |
|
Wall Thickness |
6.6 mm (SDR17, PE100) |
|
Burst Pressure |
≥1.8 MPa (3 times the PN rating) |
|
Applicable Temperature |
-20℃ to 40℃ (up to 60℃ for short-term use) |
Color identification:
Black (general purpose, contains 2.5% carbon black for UV resistance)
Blue stripes (for drinking water only, in accordance with GB/T 17219)
1. Low-pressure water supply system
Rural centralized water supply: DN90~DN160 PN6 pipes as main pipeline network
Community secondary water supply: branch pipes (DN50 or less) connected to booster equipment
2. Agricultural irrigation
Sprinkler main pipe: resistant to pesticide/fertilizer corrosion, life span over 20 years
Drip irrigation system: used with 16mm branch pipes, working pressure 0.3~0.5MPa
3. Drainage and sewage treatment
Rainwater discharge: SDR17 series meets the needs of non-pressure gravity flow
Septic tank outlet pipe: resistant to H₂S gas corrosion
4. Industrial circulating water
Cooling water circuit: PN6 pipes are used for low-pressure circulation systems (need to be installed in a dark place)
5. Temporary engineering pipelines
Construction site water supply and drainage: quick plug-in connection, removable
|
Pressure Rating |
Corresponding SDR (PE100) |
Application Scenario |
|
PN6 |
SDR17 |
Low-pressure water supply, drainage |
|
PN8 |
SDR13.6 |
Medium-pressure municipal pipeline network |
|
PN10 |
SDR11 |
High-pressure water transmission, industrial pipelines |
Selection suggestions:
PN6 is preferred for underground burial (low cost, good flexibility)
When there is a water hammer effect, it needs to be upgraded to PN8
Hot-melt connection:
Applicable to DN≥90mm pipes, requiring a dedicated Hdpe Pipe Welding Machine
(heating plate temperature 210±10℃)
Welding pressure 0.15~0.3MPa, cooling time ≥ pipe wall thickness×1.5 (minutes)
Electric fusion connection:
DN20~DN315 is universal, and PN6-level electric fusion pipe fittings need to be matched
Power-on time refers to the pipe fitting QR code parameters (usually 120-300 seconds)
Flange connection:
Equipped with PN6 flange (bolt torque needs to be tightened according to the standard)
Q: Can PN6 pipes be used for gas transportation?
A: No! Special gas pipes must comply with GB 15558.1, and the pressure level is usually above PN10.
Q: Can PN6 and PN8 pipes be mixed?
A: Mixing is strictly prohibited! The welding parameters and pressure bearing capacity of different pressure levels do not match.
Media compatibility: When transporting acidic and alkaline liquids, the chemical resistance level of HDPE must be confirmed
Deep burial requirements:
The buried depth under the roadway is ≥1.0 meters, and a sand cushion layer is required for protection
Seasonal frozen soil: In cold areas, an insulation layer must be added or pipes with lower SDR (larger wall thickness) must be selected
PN6 HDPE pipes have become the mainstream choice for low-pressure fluid transportation due to their economy and reliability. It is recommended to select a comprehensive model based on the actual working pressure, medium temperature and installation environment, and strictly follow the welding process specifications to ensure system safety.
