Which is better, HDPE or PE? What are their respective characteristics?

2025-08-26

HDPE (high-density polyethylene) and PE (polyethylene) are different types of the same material family, and the choice between the two depends on the specific application scenario. The following is a comparison and analysis of their core features:

1. Material Nature

PE (Polyethylene): A broad term encompassing various density types (LDPE, LLDPE, HDPE, etc.).

HDPE (High-Density Polyethylene): A type of PE with a density ≥ 0.941 g/cm³, minimal molecular chain branching, and high crystallinity.

2. Key Performance Comparison

Characteristics	HDPE	Ordinary PE (LDPE as an example)
Density	0.941-0.965 g/cm³	0.910-0.925 g/cm³ (LDPE)
Tensile Strength	20-32 MPa	8-20 MPa
Temperature Range	-50°C to 80°C (short-term up to 100°C)	-50°C to 60°C (short-term 70°C)
Chemical Resistance	Resistant to acids, alkalis, and solvents (except oxidizing acids)	Easily swells in hydrocarbon solvents
Moisture Permeability	Extremely low (<0.1 g·mm/m²·day)	High (approximately 0.5-1 g·mm/m²·day)
Price	Higher (approximately 20%-30% more expensive than LDPE)	Lower

3. Application scenarios and advantages of PE pipe fittings

Building Water Supply and Drainage System

Indoor hot and cold water pipes

Use PE-RT (heat-resistant polyethylene) fittings, temperature resistance ≤ 80°C, working pressure ≤ 1.6 MPa

Advantages: Leak-free hot-melt connections, resistant to water hammer (instantaneous pressure ≥ 2.5 times rated pressure)

Example: Connecting branch pipes to a residential floor heating manifold

Outdoor drainage network

Use HDPE double-wall corrugated pipe, with a ring stiffness ≥ 8 kN/m² (SN8 grade)

Features: Flexible joints adapt to foundation settlement, acid and alkali corrosion resistance (pH 2-12)

Applications: Residential rainwater collection systems, septic tank outlet pipes

Municipal Engineering

Scenario	Fitting Type	Key Technical Parameters
Gas Transmission	PE100 Ball Valve/Tee	Pressure Resistance ≥ PN16, ISO 4437 Certified
Water Main Pipe	Electrofusion Flange Sleeve	Socket Depth ≥ 1.5 Pipe Diameters, Burst Pressure ≥ 4 MPa
Cable Sleeve	PE Solid Wall Pipe + Right-Angle Elbow	Inner Wall Friction Coefficient ≤ 0.08 (Reduces Threading Resistance)