With the continuous development of my country's economy, the country vigorously develops the energy industry. Long-distance oil and gas pipelines are an important way of energy protection. In the process of anti-corrosion construction of oil and gas pipelines, the surface treatment of steel pipes is one of the key factors that determine the service life of pipeline anti-corrosion First, it is the premise of whether the anti-corrosion layer can be firmly combined with the steel pipe. It has been verified by research institutions that the life of the anti-corrosion layer depends on factors such as the type of coating, coating quality and construction environment, and the surface treatment of steel pipes has an impact on the life of the anti-corrosion layer. The surface requirements of steel pipes are constantly explored and summarized, and the surface treatment methods of steel pipes are continuously improved.
1. Cleaning of steel pipes
Use solvents and emulsions to clean the steel surface to remove oil, grease, dust, lubricants and similar organic matter, but it cannot remove rust, scale, welding flux, etc. on the steel surface, so it is only used as an auxiliary means in anti-corrosion production.
2. Derusting tools for steel pipes
Mainly use tools such as wire brushes to polish the steel surface, which can remove loose or raised scale, rust, welding slag, etc. The rust removal by hand tools can reach Sa2 level, and the power tool rust removal can reach Sa3 level. If the iron oxide scale is firmly attached to the surface of the steel, the rust removal effect of the tool is not ideal, and the anchor pattern depth required for anti-corrosion construction cannot be reached.
3. Pickling of steel pipes
Generally, chemical and electrolytic methods are used for pickling treatment. Only chemical pickling is used for pipeline anticorrosion, which can remove scale, rust, and old coatings. Sometimes it can be used as retreatment after sandblasting and rust removal. Although chemical cleaning can achieve a certain degree of cleanliness and roughness on the surface, its anchor pattern is shallow and it is easy to pollute the environment.
