PE Sheathing

PE sheathing compound is a polyethylene-based jacket formulation used on the outermost layer of a cable. The carrier resin is MDPE, HDPE or LLDPE depending on the application, with carbon black added for UV resistance plus antioxidants and processing aids for long service life. This is what separates a sheathing compound from raw polyolefin resin: it is a ready, balanced formulation that needs no further additives on the line.

Three things are expected from a sheath. First, water and moisture insulation; polyethylene has low water permeability, which is why it is preferred for buried and duct cables. Second, resistance to environmental stress cracking (ESCR); a cable stays under continuous strain on the drum, in the duct and during installation, and a sheath with poor ESCR cracks over time. Third, mechanical strength: abrasion during pulling, impact from stones and ground, and expansion with temperature swings.

Carbon black content governs UV resistance; for overhead and open-field lines it is expected to be around 2–3% by weight and well dispersed. Where a coloured sheath is required, UV protection is provided by the pigment and stabiliser system. The portfolio spans soft, flexible MDPE-based versions through to hard, abrasion-resistant HDPE-based ones with different hardness and flow values, with grades matching the PE sheathing types defined in IEC 60502 and DIN VDE 0207.