Plastic-coated steel pipes, based on galvanized seamless steel pipes or welded steel pipes, with the inner wall weld ribs removed, lined with food-grade polyethylene (PE) pipes of the same diameter as the galvanized pipe. The thickness of the polyethylene lining must comply with the HG/T 20538-2016 standard. After a certain amount of pressure and heating for a period of time, it takes shape, serving as an upgraded version of traditional galvanized pipes.