The straight seam steel pipe is a general name of high -frequency straight seams, buried arc straight seams, straight welding stitches, and pipeline straight seams. The high -frequency straight seam steel pipe uses the epidermis effect of high -frequency current, so that the ends of the steel plate can generate high temperature and external forces in a short time in a short period of time. Squeezing, this is a real non -electrode and cheap metal docking.
With hot -rolled coils as raw materials, the wall thickness of ERW high -frequency straight seam steel pipes can be controlled at about ± 0.2mm. The end of the steel pipe adopts the US APL standard or GB/T9711.1 standard, and the pipe end cutting is fixed. In recent years, among the natural gas pipe network engineering and natural gas companies, ERW steel pipes have been widely used as the main steel pipes of the urban pipe network. At present, ERW high -frequency direct seam steel pipes account for 60 % of the world's steel pipes.
The surface treatment of straight seam steel pipes is one of the key factors that determine the life of the pipeline's anti -corrosion use. It is the prerequisite for whether anticorrosive coatings and steel pipes can be firmly combined. Studies have shown that the service life of anticorrosive coatings depends on the type of coating, coating quality, and construction In the environment, the surface treatment of straight steel pipes on the life of anticorrosive coating is about 50 %. Therefore, it is necessary to continuously explore and summarize the surface treatment method of steel pipes in strict accordance with the requirements of the steel pipe surface anticorrosive coating specifications.
1. The cleaning of straight steel pipes is cleaned with solvent and emulsion to the surface of the steel to remove oil, oil, dust, lubricant, and similar organic matter, but it cannot remove oxide skin, rust on the surface of steel, welding, etc., can only be used as anti -corrosion production Auxiliary means.
2. If the steel surface is firmly attached to the iron oxide dirt, its rust removal effect is not satisfactory, and it cannot meet the requirements of the anchor particles of anticorrosive construction. The straight seam steel pipe rust removal tool mainly uses steel wire brushes and other tools to polish the steel surface. Manual rust removal can reach SA2 level. Power tool removal can reach SA3 level. wait.
3. The pickles of straight steel pipes are generally treated with chemical and electrolytic methods. It can be treated as re -treatment after sandblasting. Although chemical cleaning can make the surface clean and rough, the anchoring particles are shallow. It is easy to cause pollution to the environment. Pipe anticorrosion can only be treated with chemical pickling, which can remove oxidation, rust and old coatings.
