The epoxy resin composite steel pipe is a steel pipe based pipe, which is coated with plastic powder, and is coated with a plastic layer on its inner surface and a plastic layer or other material anti-corrosion layer on its outer surface. Steel-plastic composite products. Plastic coated steel pipes are classified into polyethylene coated steel pipes and epoxy resin coated steel pipes according to different inner coating materials. The product mark consists of a plastic coated composite steel pipe code, an inner coating material code and a nominal size. The water-lined plastic composite steel pipe is on the inner wall of the steel pipe, and is lined with plastic ethylene (PE), heat-resistant polyethylene (PE-RT), cross-linked polyethylene (PE-X), polypropylene (PP-R) according to the requirements of the conveying medium. Made of thermoplastic pipes such as hard polyvinyl chloride (PVC-U) and chlorinated polyvinyl chloride (PVC-C). Due to process improvements, some products have increased the outer plastic layer. The product is divided into cold-water lining plastic steel pipe and hot water lining plastic steel pipe according to the temperature of the conveying water. The product mark consists of a lined plastic pipe code, a lined plastic material code, and a nominal diameter. When consumers purchase such products, they should try to choose reputable products in large shopping malls and stores as needed.