HFFR (Halogen-Free Flame Retardant) PP (Polypropylene) filler rope is a type of cable filler material that is used to fill empty spaces in communication cables, power cables, and fiber optic cables. It is made of HFFR PP material, which means that it is halogen-free and flame retardant. This type of filler rope is used in applications where fire safety is a concern, as it has low smoke and toxicity when exposed to fire.
Semi-conductive filler rope, on the other hand, is used in high-voltage power cables to prevent the formation of air pockets and reduce the electrical stress in the cable. It is made of a semi-conductive material that has a resistivity value between that of the conductor and the insulation material. This type of filler rope helps to maintain the electrical continuity in the cable and prevents partial discharge.