High-density polyethylene (HDPE) pipes have become an important choice for water supply, gas transportation and industrial fluid transportation due to their excellent corrosion resistance, flexibility, and long life. As an international authoritative specification for HDPE pipe systems, ISO 4427 standard puts forward comprehensive requirements for material properties, dimensional tolerances, mechanical indicators, and test methods. This article will systematically analyze the key technical parameters and application value of HDPE pipes that meet ISO 4427 standards.
Overview of ISO 4427 Standard
The latest version of ISO 4427 “Polyethylene (PE) Pipe System – Water Supply” is ISO 4427:2019 released in 2019, which is suitable for drinking water delivery systems with working temperatures of 0°C~45°C and maximum working pressure (MOP) ≤25bar. The standard covers the following core contents:
Raw material grade requirements (PE80/PE100)
Pipe size series (SDR series)
Physical and chemical performance indicators
Long-term hydrostatic strength verification
Technical requirements for connectors
Marking and traceability system
Material technical requirements
1. Base resin grade
PE80: minimum required strength (MRS) 8.0MPa, suitable for medium and low pressure pipe networks
PE100: MRS 10.0MPa, with higher pressure bearing capacity, can reduce wall thickness and save costs
2. Additive specifications
Antioxidant: Need to pass the oxidation induction time (OIT) test of ISO 4427-2 (≥20 minutes)
Carbon black content: 2.0%~2.5% (mass fraction), to ensure UV protection
Heavy metal stabilizers are prohibited, in line with drinking water hygiene standards
HDPE pipe specifications iso 4427 and tolerances
1. Outer diameter series
The standard specifies two outer diameter systems:
Standard outer diameter (OD) series: based on the priority number system of ISO 4065 (such as dn90, dn110)
Average outer diameter series: ±0.3% roundness deviation is allowed
2. Wall thickness and SDR
Standard dimension ratio (SDR) = outer diameter/wall thickness, common series:
| SDR Value | Nominal pressure (PN) |
| SDR11 | PN16 |
| SDR17 | PN10 |
| SDR21 | PN8 |
Wall thickness tolerance requirement: +0.2emax (maximum deviation does not exceed 20% of the nominal value)
Mechanical performance indicators
1. Short-term performance test
Longitudinal shrinkage (110°C): ≤3% (ISO 2505)
Elongation at break: ≥350% (ISO 6259-1)
Resistance to rapid crack propagation (RCP): Pass S4 test (PE100 requirement)
2. Long-term hydrostatic strength
Pass ISO 9080 test, requirements:
20°C/50 years, 97.5% confidence lower limit (LCL) strength:
PE80: ≥8.0MPa
PE100: ≥10.0MPa
Hygiene and chemical properties
Drinking water certification: Migration test in accordance with ISO 4427-3 (such as EN 12873)
Odor and taste: ΔTOC≤4mg/L (ISO 17494)
Heavy metal precipitation: lead ≤ 5μg/L, cadmium ≤ 0.5μg/L
Connection system requirements
Electrofusion connection:
Melting zone temperature ≥ 200°C
Welding strength ≥ 90% parent material strength
Mechanical connection:
Must pass ISO 4427-4 pressure cycle test (≥ 10,000 times)
Marking and traceability
Each meter of pipe must be permanently marked with:
Production date and time code
Raw material brand (such as PE100 RC)
SDR value and standard number (ISO 4427:2019)
Manufacturer registered trademark
Application advantage analysis
Life cycle cost: 50 years of service life, maintenance cost is 60% lower than metal pipes
Fluid efficiency: Hazen-Williams coefficient C=150, reducing pumping energy consumption
Environmental adaptability: -40°C~60°C working range, excellent earthquake resistance
HDPE pipes that meet ISO 4427 standards ensure the safety and economy of water supply systems through systematic performance specifications. With the application of new materials such as PE100-RC, HDPE pipes will play a greater role in higher pressures (PN25) and harsh environments (such as mineralized water transportation) in the future.
