Plastic-lined steel pipes, based on galvanized seamless steel pipes and welded steel pipes, after the inner wall weld ribs are removed, food-grade polyethylene (PE) pipes of the same diameter as the galvanized pipe are inserted. The thickness of the polyethylene lining must meet the HG/T 20538-2016 standard. After a certain period of pressure and heat treatment, it takes shape, serving as an upgraded version of traditional galvanized pipes.