Water supply coated steel pipes generally use straight seam high-frequency welded steel pipes and spiral seam submerged arc welded steel pipes as the base pipes, and the material is mostly Q235B. The epoxy resin powder coating inside the coated steel pipe can exceed 400 μ m, and the outer polyethylene powder coating can exceed 1300 μ m, effectively improving the corrosion resistance of the steel pipe, which is 2-3 times that of general anti-corrosion steel pipes.