Environment-friendly polypropylene fire-resistant torsion-resistant middle and low voltage cable and production process thereof

The environment-friendly polypropylene fire-resistant torsion-resistant middle and low voltage cable comprises at least one strand of metal wire core, each strand of metal wire core is wrapped with an insulating layer, and a plurality of strands of metal wire cores form a bundle in a round mode; the inner insulating layer is made of a polypropylene material, wraps the outer surfaces of the multiple strands of metal wire cores, and fills gaps among the multiple strands of wire cores; the high-temperature expansion layer is wrapped on the outer surface of the inner insulating layer; the armor layer is formed by spirally winding a plurality of strands of metal wires on the outer surface of the high-temperature expansion layer and shielding the outer surface of the high-temperature expansion layer; the outer surface of the armor layer is wrapped with the heat insulation layer, and the outer surface of the heat insulation layer is coated with resistance reducing powder; and the outer insulating layer is made of a