Long-distance oil and gas pipelines are an important way to ensure energy. In the process of anti-corrosion construction of oil and gas pipelines, the surface treatment of straight seam steel pipes
is one of the key factors that determine the service life of pipeline anti-corrosion. It is whether the anti-corrosion layer and the steel pipe can be firmly combined the premise.
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. Standardize the requirements for the surface of steel pipes, constantly explore and summarize, and continuously improve the surface treatment methods of steel pipes.
The cleaning of straight seam steel pipes uses solvents and emulsions to clean the steel surface to remove oil, grease, dust, lubricants and similar organic substances, but it cannot remove rust, oxide skin, welding flux, etc. on the steel surface, so it is used in anti-corrosion production. only as an aid.
The tool to remove the rust of the straight seam steel pipe mainly uses tools such as wire brushes to polish the surface of the steel, which can remove the loose or warped oxide scale, rust, welding slag, etc. The rust removal of manual tools can reach Sa2 level, and the rust removal of power tools can reach Sa3 level. If the steel surface is adhered to a firm scale of iron oxide, the rust removal effect of the tools is not ideal, and the anchor pattern depth required for anti-corrosion construction cannot be achieved.
The pickling of straight seam steel pipes is generally carried out by chemical and electrolytic methods, and only chemical pickling is used for pipeline anti-corrosion, which can remove oxide scale, rust, and old coatings, and can sometimes be used as reprocessing after sandblasting and rust removal. . Although chemical cleaning can make the surface achieve a certain degree of cleanliness and roughness, its anchor pattern is shallow and it is easy to cause pollution to the environment.
Tips: Welded steel pipes are divided into two basic forms according to the distribution of welds: straight seam steel pipes and spiral seam pipes. The most widely used welding method for straight seam steel pipe (ERW/LSAW) and spiral seam pipe (SSAW)
is submerged arc welding (SAW), which has good quality, high productivity, mature and stable technology.