Causes of PE Sheath Cracking
Polyethylene (PE) is widely used for insulation and sheathing of power cables because of its good mechanical strength, toughness, heat resistance, insulation and chemical stability. However, due to the structure of PE itself, it has poor environmental stress cracking resistance, especially when PE is used as the outer sheath of armored cables with large cross-section, the cracking problem is especially prominent. Mechanism of PE sheath cracking PE sheath cracking mainly has the following two cases: one is the environmental stress cracking, refers to the cable after installation and operation, the sheath in the combination of the role of stress or environmental media contact, from the surface of the brittle cracking phenomenon. This cracking is generally caused by two factors: one is the presence of internal stress in the sheath, and the other is the cable sheath has been in contact with polar liquids for a long time. This cracking mainly depends on the material itself to r...