Polyethylene is odorless, non-toxic, waxy, and has excellent low temperature resistance (the minimum working temperature can reach -70 ~ -100 degree C), good chemical stability, and can withstand most of the acid and alkali corrosion (anaerobic acid). It is insoluble in the average solvent at room temperature, and the water absorption rate is low, but because it is a linear molecule, it is dissolved slowly, and it does not swell in certain organic solvents, so it has excellent electrical insulation performance.

Inner wall anti -antichematic layer: In order to prevent corrosion in the pipeline, reduce friction, and improve production capacity, apply a layer of film on the inner wall of the pipeline. Common coatings include amine solid epoxy resin and polyamide epoxy resin. The thickness of the coating is 0.038-0.2mm. In order to ensure that the coating and the tube wall are firm, the inner wall of the tube must be processed. Since the 1970s, the anticorrosive coatings on the outer wall of the steel pipe have chosen the same paint, whether it is domestic or abroad, which has made this coating a trend of anti -corrosion treatment of steel pipes.

Anti-corrosion steel pipe insulation layer: In order to reduce the heat dissipation of medium and small-caliber heat conductive oils or oil pipeline soil, the corruption composite layer is set up outside the pipeline. The commonly used insulation material is a hard polyurethane foam with a temperature of -185 ~ 95 degrees. The texture of this material is soft. In order to improve its strength, a layer of high -density polyethylene is coated on the thermal insulation layer to form a composite structure to prevent groundwater from penetrating into the insulation layer.