Why Do PE Pipes Have a “Shelf Life”? — Understanding Storage Standards
Although PE (polyethylene) pipes and fittings contain stabilizers such as carbon black and antioxidants, they are still thermoplastics. Over time, exposure to heat, light, or oxygen gradually breaks down their molecular structure, even during storage. This slow aging process typically appears in three forms:
Sunlight Exposure:
UV radiation damages the molecular chains of PE, causing surface chalking, brittleness, or cracking.
High Temperatures:
Long-term heat accelerates the depletion of antioxidants, reducing material toughness.
Prolonged Storage:
Even in shaded and ventilated warehouses, PE materials slowly oxidize, weakening mechanical strength.
To ensure construction safety and long-term pipeline performance, industry standards define specific storage limits for PE pipes and fittings.
Storage Duration Standards
PE Water Supply Pipes:
Generally, pipes should be used within 18 months, and fittings within 24 months after production. Beyond this, performance tests must confirm compliance before use.
PE Gas Pipes:
Requirements are stricter — outdoor-exposed or overaged materials must undergo sampling tests. Typically, pipes can be stored for up to 4 years, and sealed fittings for 6 years, with inspections covering hydrostatic strength, fusion strength, and elongation at break.
