In the construction process of oil and gas pipelines, the surface treatment of straight seam steel pipe is one of the key factors to determine the service life of pipelines. According to the research of professional institutions, the anti-corrosion coating life depends on coating type, coating quality, construction environment and other factors, the impact of surface treatment on the anti-corrosion coating life of straight seam steel tube accounts for about 50%. Therefore, the surface treatment method of straight seam steel tube should be continuously improved in strict accordance with the requirements of the anti-corrosion coating specification on the surface of straight seam steel tube.
Straight Seam Steel Pipe
In addition to the straight seam steel tube embroidery methods mainly have the following:
The use of solvent, emulsion cleaning of steel surface, in order to achieve the removal of oil, grease, dust, lubricants and similar organic matter, but it can not remove the rust on the surface of steel, oxide, welding, and so on, so only as an auxiliary means in the prevention work.
Generally with chemical and electrolysis two methods to do pickling treatment, pipeline corrosion only chemical pickling, can remove the oxide, rust, old coating, and sometimes can be used as a sandblasting after the rust treatment.Although chemical cleaning can make the surface reach a certain degree of cleanliness and roughness, but the anchor grain is shallow, and easy to cause pollution to the surrounding environment.
3. Tool derusting
Mainly use steel wire brush and other tools to polish the steel surface, can remove loose oxide, rust, welding slag and so on.Manual tool derusting can reach Sa2 level, power tool derusting can reach Sa3 level, if the steel surface attached to a firm iron oxide, tool derusting effect is not ideal, can not reach the anti-corrosion construction requirements of anchor depth.
After spraying, not only the physical adsorption on the surface of the pipe can be expanded, but also the mechanical adhesion between the coating and the surface of the pipe can be enhanced.Therefore, spray rust removal is the ideal way of pipeline corrosion removal.Generally speaking, shot peening and derusting are mainly used for internal surface treatment of pipes, while shot blasting and derusting are mainly used for external surface treatment of straight seam steel pipes.In the production process, relevant technical indicators of derusting should be strictly required to prevent secondary damage to the straight seam steel pipe caused by operational mistakes. The straight seam steel pipe will be smoother in appearance compared with the straight seam steel pipe before the elimination of embroidery. The elimination of embroidery of straight seam steel pipe is a frequently used technology in the steel pipe industry.