TPEP anti-corrosion steel pipe (i.e. outer 3PE inner EP anti-corrosion steel pipe) is an upgraded product based on outer polyethylene inner fusion bonded epoxy composite steel pipe, and is currently a more suitable anti-corrosion form for buried long-distance pipelines. The outer wall of TPEP anti-corrosion steel pipe adopts a hot melt wrapping process, with a bottom layer of epoxy resin, an intermediate layer of adhesive, and an outer layer of polyethylene forming a three-layer structure of anti-corrosion layer. The inner wall adopts a hot spray epoxy powder anti-corrosion method