How to maintain steel pipes

　　With the sustainable development of China's economy, the country is vigorously developing the energy industry. Long oil and gas pipelines are an important way to ensure energy. During the 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, and it is the prerequisite for the solid combination of anti-corrosion coating and steel pipes. It is verified by the research institute that the service life of the anti-corrosion coating depends on factors such as coating type, coating quality and construction environment, and the influence of steel pipe surface treatment on the service life of the anti-corrosion coating accounts for about 50%. Therefore, it is necessary to strictly follow the requirements of the anti-corrosion coating specification on the steel pipe surface, constantly explore and summarize, and constantly improve the steel pipe surface treatment method.

　　1. Cleaning of steel pipe

　　Solvents and emulsions are used to clean the steel surface to remove oil, grease, dust, lubricant and similar organic matters. However, they cannot remove rust, oxide skin, welding flux, etc. on the steel surface, so they are only used as auxiliary means in anti-corrosion production.

　　2. Tool derusting of steel pipe

　　Steel wire brush and other tools are mainly used to polish the steel surface to remove loose or cocked oxide skin, rust, welding slag, etc. Rust removal by manual tools can reach Sa2, and that by power tools can reach Sa3. If the steel surface is firmly attached with oxide scale, the rust removal effect of tools 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. Only chemical pickling is used for pipeline corrosion prevention, which can remove oxide scale, rust and old coating. Sometimes, it can be used as the re treatment after sand blasting. Although chemical cleaning can make the surface reach a certain degree of cleanliness and roughness, its anchor lines are shallow and easy to pollute the environment.