Coating anti-corrosion is a uniform and dense coating formed on the surface of rust-removed metal pipes. The coating can isolate it from various corrosive media. Steel pipe anti-corrosion coatings increasingly use composite materials or composite structures. These materials and structures must have good dielectric properties, physical properties, stable chemical properties, and a wide temperature range.

Exterior wall anti-corrosion coatings: Types and application conditions of steel pipe exterior wall coatings. Inner wall anti-corrosion coating This film is applied to the inner wall of the steel pipe to avoid corrosion of the steel pipe, reduce friction resistance, and increase the dosage. Commonly used coatings are amine-cured epoxy resin and polyamide epoxy resin, with a coating thickness of 0.038 to 0.2 mm. To ensure that the coating is firmly bonded to the pipe wall.

The inner wall of the tube must be surface-treated. Since the 1970s, the same materials have been used to coat the inner and outer walls of steel pipes, making it possible to coat both the inner and outer walls of steel pipes simultaneously. Anti-corrosion and thermal insulation coatings are applied to small and medium-diameter heat transfer crude oil or fuel oil steel pipes to reduce heat dissipation from the steel pipes to the soil.

A composite layer of insulation and anti-corrosion is added to the outside of the steel pipe. The commonly used thermal insulation material is rigid polyurethane foam. The suitable temperature is that this material has a soft texture. To increase its strength, a layer of high-density polyethylene is applied to the outside of the insulation to form a composite structure to prevent underground water from penetrating the insulation.