Why Do PE Pipes Have a “Shelf Life”?

PE is a thermoplastic material. Although carbon black and antioxidants are added during production, its molecular structure still gradually degrades under heat, light, or oxidative conditions. Even when stored in a warehouse without use, slow aging can still occur. This is mainly reflected in the following aspects:

Ultraviolet rays can break the molecular chains of PE, causing the pipe surface to chalk, become brittle, or even crack.

Prolonged exposure to high temperatures accelerates the consumption of antioxidants, leading to a loss of material toughness.

Even in a cool, ventilated warehouse, polyethylene materials undergo slow oxidation, which may reduce their mechanical strength.

Therefore, to ensure construction safety and long-term pipe performance, industry standards specify clear requirements for the storage period of PE pipes and fittings.