Straight seam steel pipes can be divided into many different specifications and names, including straight seam welded pipes, double-sided submerged arc welded pipes, thick-walled straight seam steel pipes, straight seam steel pipes, large diameter straight seam steel line pipes, API5L straight seam steel pipes, JCOE large diameter straight seam welded pipe, large diameter straight seam welded pipe, welded straight seam steel pipe, double-sided submerged arc spiral welded steel pipe, straight seam structural pipe, PSL2 steel pipe, X steel grade steel pipe, L steel grade steel pipe, large diameter thick wall submerged arc welded steel pipe, Large diameter straight seam steel pipe, carbon steel straight seam steel pipe, ordinary carbon steel pipe, API5L, X80 steel pipe. Straight seam steel pipes are mainly used in water supply projects, the petrochemical industry, the chemical industry, the electric power industry, agricultural irrigation, and urban construction. For liquid transportation: water supply and drainage. For gas transportation: gas, steam, liquefied petroleum gas; for structural use: piling pipes, docks, roads, building structure pipes, etc.
1. The site or warehouse where straight seam steel pipe products are kept should be located in a clean place with smooth drainage and away from factories and mines that produce harmful gases or dust. Remove weeds and debris on the site and keep the steel clean;
2. It must not be stacked together with acid, alkali, salt, cement, and other materials that are corrosive to steel in the warehouse. Different types of steel should be stacked separately to prevent confusion and contact corrosion;
3. Large steel sections, rails, steel plates, large-diameter steel pipes, forgings, etc. can be stacked in the open air;
4. Small and medium-sized steel, wire rods, steel bars, medium-diameter steel pipes, steel wires, and steel wire ropes, etc., can be stored in a ventilated material shed, but the top is covered with a thatch;
5. Some small steel products, thin steel plates, steel strips, silicon steel sheets, small diameter or thin-walled steel pipes, various cold-rolled and cold-drawn steel products, and high-priced and corrosive metal products can be stored in the warehouse;
6. The warehouse should be selected based on geographical conditions. Generally, ordinarily, closed warehouses are used, that is, warehouses with walls on the roof, tight doors and windows, and ventilation devices.
Regarding the effect of deoxidizer on straight seam steel pipes, we summarized the following content:
For ω(Als≤0.01% straight seam welded pipe, the use of two deoxidants has little effect on the total oxygen content in the steel after VD treatment, and both can control ω(T.O below 20×10-6; Si-Al-Ba deoxidation Finally, lower total oxygen content can be obtained in each process, and the deoxidation effect of each process is stronger than that of Si-Ca.
When two different deoxidizers, Si-Ca and Si-Al-Ba, are used for straight seam welded pipes, the number and size of inclusions during the smelting process are greatly different. After Si-Al-Ba deoxidation, the number of inclusions in each process is less than After Si-Ca is deoxidized, its size is smaller. When two different deoxidizers, Si-Ca and Si-Al-Ba, are used for straight seam welded pipes, obvious secondary oxidation of the molten steel occurs during the casting process, but the secondary oxidation of the Si-Al-Ba deoxidized molten steel is severe. The inclusion composition and aluminum inclusion content in forged materials are quite different. When Si-Al-Ba is used for deoxidation, the inclusions in the forged materials are mainly block and chain alumina. When the straight seam welded pipe is forged using Si-Ca for deoxidation, The inclusions in the material are mainly strip-shaped silicomanganese aluminate composite inclusions; the content of aluminum inclusions in Si-Ca alloy deoxidized forged materials is less than that of Si-Al-Ba alloy deoxidized.
In addition, the production process of thick-walled straight seam steel pipes and large-diameter thick-walled steel pipes generally includes hot rolling, hot coiling, casting, and other production methods. The double-sided submerged arc welding production process is generally used when processing large-diameter thick-walled steel pipes. The products go through multiple processes such as bending, jointing, internal welding, external welding, straightening, and flattening to meet the requirements of petrochemical standards. Thick-walled straight seam steel pipes are mainly used for body support parts, such as bridge piling, submarine piling, and high-rise building piling. The materials used are generally Q345B and Q345C. Q345D is also used in areas with lower temperatures. Q345E large-diameter thick-walled steel pipes are mostly used in large-scale steel structure construction.
Post time: Feb-19-2024