Corrosion-resistant spiral steel pipes with a 3PE protective coating combine the benefits of high-density polyethylene coating and fused epoxy powder. This system ensures a strong bond between the epoxy powder and the steel pipe surface, utilizes the high-density polyethylene's resistance to mechanical damage, and the special adhesive layer between the two layers forms a composite structure with molecular bond integration, thereby achieving a favorable combination of corrosion resistance and mechanical properties.