Welded black annealed steel pipes are divided into furnace welded pipes, electric resistance welding (resistance welding) pipes and active arc welded pipes due to different welding processes. Due to different welding forms, they are divided into curved welded pipes and spiral welded pipes, round welded pipes and special-shaped (square, flat, etc.) welded pipes. ) welded pipes because of their end shape.
Black steel pipe welded steel pipe is made of steel plate through butt joint or spiral seam welding and rolling into tubular shape. It is divided into welded steel pipes for low-pressure fluid transportation, spiral seam welded steel pipes, indirect coil welded steel pipes, and welded steel pipes.
The service life of steel pipe anti-corrosion coating depends on factors such as coating type, coating quality and construction environment. The impact of steel pipe surface treatment on the service life of anti-corrosion coating accounts for about 50%. Therefore, the application of the scientific steel pipe rust removal method and the application of the surface treatment technology of the cloth pipe have greatly improved the service life of the steel pipe.
Cleaning the steel surface with solvents and emulsions can remove oil, grease, dust, lubricants and similar organic matter, but cannot remove rust, scale and flux on the steel surface, so it is only used as an auxiliary means in anti-corrosion production.
Mainly use tools such as wire brushes to polish the steel surface, which can remove loose or warped scale, rust, welding slag, etc. The rust removal effect of hand tools can reach Sa2 level, and the rust removal effect of electric tools can reach Sa3 level. If there is a firm scale attached to the surface of the steel, the derusting effect of the tool is not satisfactory, and the anchor line depth required for anti-corrosion construction cannot be reached.
Seamless steel pipes are used in liquid and gas piping in various industries. Welded pipes can be used in water pipelines, gas pipelines, heating pipelines, electrical pipelines, etc.
A hollow section of steel whose length is much longer than a curve or circumference. According to the cross-sectional shape, it is divided into round, square, rectangular and special-shaped steel pipes; according to the number of materials, it is divided into carbon structural steel pipes, low alloy structural steel pipes, alloy steel pipes, and composite steel pipes; , Steel pipes for thermal machinery tools, steel pipes for petrochemical industry, steel pipes for mechanical equipment manufacturing, steel pipes for geological drilling, steel pipes for high-pressure mechanical tools. According to the consumption process, it is divided into seamless steel pipe and weld pipe.
Post time: Dec-26-2022