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Choosing a corrosion-resistant substrate is essential for improving the anti-corrosion performance of pipelines, so the selection of the substrate is particularly important. Corrosion-resistant substrates are divided into two categories: corrosion-resistant metal substrates and corrosion-resistant non-metallic substrates. Commonly used corrosion-resistant metal substrates today include stainless steel, corrosion-resistant alloys, non-ferrous metals, and their alloys. Stainless steel pipes exhibit good corrosion resistance in oxidizing acids as well as in environments such as the atmosphere and water. Therefore, the stainless steels used for oil transport pipelines in China are: 9Cr1Mo martensitic stainless steel, 13Cr martensitic stainless steel, and 22-25Cr α-γ dual-phase stainless steel. Iron-nickel-based corrosion-resistant alloys possess excellent corrosion resistance, being able to withstand various forms of corrosive degradation such as stress corrosion, pitting, and crevice corrosion, in addition to having good mechanical and processability properties. Commonly used corrosion-resistant non-metallic substrates include: fiberglass, plastics, rubber, and ceramics, etc. Fiberglass oil pipes are twice as expensive as J-55 pipes, but they significantly reduce costs related to equipment installation and maintenance, as well as expenses for chemical consumables. Plastic pipes are not only corrosion-resistant but also have a simple manufacturing process, which is beneficial to the environment. Plastic pipes commonly used today are divided into two categories: the first category is steel pipes with an inner lining ； The second category is high-strength polyethylene pipes.