HDPE (high-density polyethylene) pipes are widely used in water supply and drainage, gas transportation, industrial fluid transportation and other fields due to their excellent corrosion resistance, flexibility, long life and environmental protection characteristics. However, in actual projects, the selection of HDPE pipe diameters directly affects the flow, pressure, energy consumption and overall cost of the system. This article will introduce in detail the influencing factors, standard specifications and selection recommendations of HDPE pipe diameters to help you optimize the design of the pipeline system.
Why is HDPE pipe diameters so important?
1. Flow and efficiency optimization
A pipe diameter that is too small will lead to excessive flow velocity, increase friction loss and reduce transportation efficiency;
A pipe diameter that is too large will increase costs and cause waste of resources.
Puhui Industry provides HDPE pipes of various diameters, from DN20 to DN2000, to meet different flow requirements and ensure efficient operation of the system.
2. Pressure and durability
Reasonable selection of diameter can effectively reduce the internal pressure of the pipeline, reduce the risk of pipe bursting and extend the service life.
3. Ease of installation
Large-diameter HDPE pipes are light in weight, flexible, easy to transport and lay, and are especially suitable for long-distance projects.
Puhui Industry provides a variety of connection solutions (such as hot melt and electric melt) to meet different diameter requirements and greatly reduce the difficulty of construction.
HDPE pipe diameters standard specifications
The diameter of HDPE pipes is usually marked according to the nominal diameter (DN) or the outer diameter (OD). Common specifications include:
1. Small diameter pipes (DN20-DN110): suitable for household water supply, indoor drainage, agricultural drip irrigation and other scenarios.
2. Medium diameter pipes (DN125-DN400): commonly used in municipal water supply, industrial pipelines, sewage treatment, etc.
3. Large diameter pipes (DN450-DN1200 and above): suitable for long-distance water delivery, large drainage systems, mine transportation, etc.
Standards in different countries and regions may vary. Common standards include:
1. ISO 4427 (international standard)
2. GB/T 13663 (Chinese national standard)
3. ASTM D3035 (American standard)
How to choose the right pipe diameter?
1. Flow demand
The primary factor in pipe diameter selection is flow (Q), which is usually calculated according to the following formula:
Q=A×vQ=A×v
Where:
QQ = Flow (m³/s)
AA = Pipe cross-sectional area (m²)
vv = Flow rate (m/s, recommended 0.5-2.5 m/s)
Pipe diameter is too small → Flow rate is too high → Increase friction loss and reduce transportation efficiency.
Pipe diameter is too large → Cost increases → May cause waste of resources.
2. Pressure rating (PN value)
The pressure rating (PN) of HDPE pipe indicates its maximum pressure bearing capacity. Common ones are:
1. PN6 (0.6MPa)
2. PN8 (0.8MPa)
3. PN10 (1.0MPa)
4. PN16 (1.6MPa)
Large-diameter pipes usually require higher pressure ratings to ensure long-term stable operation.
3. Installation environment
1. Underground burial: soil pressure and external loads need to be considered, and pipes with higher ring stiffness (such as SN8, SN16) are usually selected.
2. Open-air laying: UV protection needs to be considered, and HDPE pipes with UV-resistant formula can be selected.
3. Long-distance transportation: Large-diameter pipes can reduce the number of pumping stations and reduce energy consumption.
Application Cases
| Application Areas | Recommended diameter (DN) | Features |
| Domestic water supply | DN20-DN63 | Small diameter, good pressure resistance |
| Municipal water supply | DN110-DN400 | Medium to large diameter, high pressure bearing capacity |
| Agricultural irrigation | DN50-DN250 | Anti-clogging, corrosion-resistant |
| Industrial sewage | DN200-DN800 | Chemical and impact resistant |
| Gas transportation | DN63-DN315 | High air tightness, anti-cracking |
Selecting the right HDPE pipe diameters is the key to ensuring efficient, economical, and long-term stable operation of the project. When selecting, factors such as flow, pressure, and installation environment should be considered comprehensively, and relevant international or national standards should be referred to. Puhui Industry provides a full range of HDPE pipes, covering more than DN20 to DN1200 specifications, and can customize pressure levels and ring stiffness according to customer needs to ensure that your project gets the best solution.
