ERW steel pipes have been widely used as the main steel pipes in urban pipeline networks. Currently, ERW high-frequency straight seam steel pipes account for 60% of the world's steel pipe use ratio.
Straight seam steel pipe is a general term for high-frequency straight seam, submerged arc straight seam, electric welded straight seam, pipeline straight seam, etc. High-frequency straight seam steel pipe (ERW steel pipe) uses the skin effect of high-frequency current to generate high temperature and external force at both ends of the steel plate in a short time Squeeze, this is a true base metal butt without electrodes. Using hot-rolled coils as raw materials, the wall thickness of ERW high-frequency straight seam steel pipes can be controlled to about ±0.2mm. The end of the steel pipe adopts the American APL standard or GB/T9711.1 standard. The pipe end is cut and the conveying length is fixed. In recent years, in natural gas pipeline network projects and natural gas enterprises,
Longitudinal seam steel pipe often refers to the double-sided submerged arc straight seam steel pipe produced by JCOE. It adopts JCOE cold forming process. The welding seam uses welding wire and flux. It is called submerged arc welding straight seam steel pipe. The main production process is flexible submerged arc welding straight seam steel pipe Seam steel pipes can produce arbitrary specifications and wall thicknesses between 325 mm and 1420 mm, which greatly meets the world's steel pipe size standards, while high-frequency straight seam steel pipes are usually used for internal specification production.
Long-distance oil and gas pipelines are an important way to ensure energy. In the anti-corrosion construction process of oil and gas pipelines, the surface treatment of straight seam steel pipes is one of the key factors that determine the anti-corrosion service life of the pipeline. It is the premise of whether the anti-corrosion coating can be firmly combined with the steel pipe. Research has shown that the service life of the anti-corrosion coating depends on the coating. Layer type, coating quality and construction environment, the effect of surface treatment of straight seam steel pipe on the life of anti-corrosion coating is about 50%. Therefore, the surface treatment methods of steel pipes should be continuously explored and summarized in strict accordance with the requirements of the anti-corrosion coating specifications on the surface of steel pipes.
1. 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 matter, but it cannot remove oxide scale, rust on the steel surface, flux, etc., and can only be used as anti-corrosion production Auxiliary means.
2. If the steel surface is firmly attached to the iron oxide scale, its rust removal effect is not ideal, and it cannot meet the requirements of anti-corrosion construction for anchoring particle depth. Straight seam steel pipe rust removal tools mainly use wire brushes and other tools to polish the steel surface. Manual rust removal can reach SA2 level, and power tool rust removal can reach SA3 level, which can remove loose or raised oxide scale, rust, and welding slag. Wait.
3. The pickling of straight seam steel pipes is generally treated by chemical and electrolytic methods, which can be used as reprocessing after sandblasting and rust removal. Although chemical cleaning can make the surface clean and rough to a certain degree, its anchoring particles are relatively shallow. It is easy to cause pollution to the environment. Pipeline anticorrosion can only be treated with chemical pickling, which can remove oxide scale, rust and old coatings.
