steel tube

　　 LSAW steel pipe after heat treatment is a new technology to eliminate residual stress. After the material is preheated before welding to heat treatment temperature and the butt welding process to maintain the temperature of the continuously heated member, after the welding is completed using its thermal insulation cotton allowed to cool slowly. This method can effectively reduce the welding residual stress and improve resistance to stress corrosion of metals. 　　Internal weld NDT since the large steel pipes in water supply project belongs, especially the thickness t = 30mm steel is used as a pipe bridge, both to withstand water pressure inside, but also the burden of its own weight and the water formed by a steel pipe moment, so the welding quality requirements are particularly high. For pipe bridge with a thickness t = 30mm large-diameter pipe, the longitudinal seam and girth weld belong to a class, require 100% of X-ray film examination and 100% ultrasonic flaw detection; and th...

　　The galvanized steel pipe production lines have special requirements, especially for the production environment, it is nesscary to production quality and efficiency improvement. Particularly, galvanized steel need a stable enviroment to production. 　　First, Ensure that the production line for delicate work processes, equipment, heating, ventilation, drainage, etc., all work are revolves around the ritual of quality. As long as the quality of the galvanized steel is good, all other factors can be achieved. 　　The use of galvanized steel is very widespread, especially in natural gas pipes, heating and other high strength and quality of the pipeline industry, galvanized steel pipe has a obvious advantages than others. If the galvanized used as plumbing, a large amount of rust inner tube after several years of use, the outflow yellow water pollution not only to ware but also mixed with not smooth inner wall of the breeding of bacteria. And corrosion leads to high heavy metal content ...

　　TP347H high-pressure boiler heat-resistant stainless steel seamless steel pipe round billet is the main material used to manufacture heat exchanger tubes, reheater tubes, steam pipes and petrochemical heat exchange tubes for large generator sets. The application environment is high temperature and high pressure, and the use environment is relatively harsh. This requires good high temperature structure stability, long-lasting performance, high temperature corrosion resistance, and good thermal processing, cold working, welding and bending. Processing performance. 　　TP347H trial chemical composition (mass fraction, %): 0.04 ~ 0.1C, ≤ 2.0Mn, ≤ 0.75Si, ≤ 0.03P, ≤ 0.01S, 9.0 ~ 12.0Ni, 17.0 ~ 19.0Cr, 8 × w (C) ~ 1.0% w (Nb). The production process is as follows: batching→EAF electric arc furnace initial refining→AOD furnace refining→die casting→finishing→heating→forging→straightening→finishing→inspection→packaging→into the warehouse. 　　The TP347H round billet was developed by using th...

　　20G and 12Cr1MoVG are representative of high-quality carbon steel and alloy steel for boilers, and have been widely used and developed in practice. 12Cr1MoVG is a low-alloy pearlitic heat-strength steel that has been developed earlier and has a relatively mature application. It has low carbon content, good processability and thermal conductivity, and has high durability and long-lasting plasticity. It is generally used in the manufacture of headers, steam pipes with steam temperatures below 540 °C, superheaters, reheaters and some castings and forgings with a metal wall temperature not exceeding 580 °C. It is the most common main steam used in high-parameter thermal power plants. One of the steels for pipes and reheater pipes. With the sharp increase of the operating parameters and single-unit capacity of power station units in China and the need for the development of high-temperature boiler pipes to large diameters, further research on high-temperature and high-strength boiler tube...

　　The production process of seamless steel pipe is mainly accomplished by tension reduction. The tension reduction process is a continuous rolling process of hollow base metal without core rod. In the production rolling process, sometimes the steel pipe is not straight, and what method can correct the tortuosity of the seamless steel pipe? 　　The seamless steel pipe is a circular, square, rectangular steel with a hollow section and no seams around it. The seamless steel pipe is formed by perforating a steel ingot or a solid tube blank, and then hot rolled, cold rolled or cold drawn. The seamless steel pipe has a hollow section and is used as a pipe for conveying fluid. Compared with a solid steel such as round steel, the steel pipe is light in weight when it has the same bending and torsional strength, and is an economical section steel, which is widely used in manufacturing structures. Parts and mechanical parts, such as oil drill pipes, automotive drive shafts, bicycle frames, and ...

　　Iron ore is mainly used in the steel industry. There are many kinds of iron minerals, and about 300 kinds of iron minerals and iron-containing minerals have been discovered, among which more than 170 are common. However, under the current technical conditions, the main industrial value is magnetite, hematite, maghemite, ilmenite, limonite and siderite. 　　Classification of magnetite 　　The chemical formula of magnetite is Fe3O4, and the theoretical iron content is 72.4%. This ore sometimes contains a composite ore of TiO2 and V2O5, which is called titanomagnetite or strontium titanomagnetite. 　　It is rarely encountered in natural pure magnetite ore, and some of the magnetite is often oxidized into semi-artificial hematite and imaginary hematite due to surface oxidation. The so-called imaginary hematite is the oxidation of magnetite (Fe3O4) to hematite (Fe2O3), but it still retains the shape of the original magnetite, so it is called imaginary hematite. 　　Magnetite has strong ma...

　　Blind flange, its function is to cut the medium in the pipe, according to the use of pressure and the form of the flange sealing surface can be divided into the following: 　　Smooth surface blind flange, used with smooth sealing surface flange, its applicable pressure range is 1.0 ~ 2.5MPa. 　　The convex blind flange has a convex surface on one side and a concave surface on the other side, and is used together with the concave and convex sealing surface flange. The pressure is 4.0 MPa and the specification range is DN25 to 400 mm. 　　The trapezoidal groove surface blind flange is used in combination with the trapezoidal groove sealing surface flange, and the pressure range is 6.4 to 16.0 MPa. Specifications range from DN25 to 300mm. 　　The "8" word blind flange is also divided into three types: smooth surface, concave surface and trapezoidal groove surface. The pressure is the same as the above three blind flanges. The difference of the "8" word blind flange ...