The main application field of stainless steel welded pipe is urban landscape and decoration engineering. It also has a considerable proportion in light industry, pharmaceutical, papermaking, sewage treatment, water supply, machinery and other fields. In chemical, chemical, chemical, petrochemical and other industries, the medium and low pressure conveying pipes with specifications of more than 159mm are generally selected and the automobile muffler also uses the rust. Steel welded pipe.
Stainless steel seamless pipe is mainly used in "three" (chemical, chemical, chemical fiber, chemical fiber), oil, power boiler, machinery, aerospace, nuclear industry, national defense industry and other fields.
Stainless steel pipe is used for oil drill
Since 1990s, the production capacity of China's oil well pipes has increased year by year, and the export volume is greater than the import volume. The self-sufficiency rate has reached over 90%. But the varieties are mostly medium and low grade steel grades such as J55 and N80, and only a small number of API high grade oil well pipes.
At present, the oil well tubes of high strength, high resistance to CO2, anti Cl- corrosion, high resistance to crushing and crushing, APIQ125, C95, L80-2 (13Cr) steel and non API standard special threaded buckles and cold regions have not yet been industrialized. With the development of petroleum industry, more and more strict technical requirements for oil well pipes are put forward. High performance and new materials are the development trend of oil well pipes. Stainless steel non magnetic drill collars, high resistance to CO, CO2 and Cl- corrosion of super ferrite stainless steel Cr13, Cr25 and other oil casing are all used in oilfield drilling and production. According to rough statistical analysis, at present, more than 10 thousand T is needed each year, and 4~5 10000 t is needed every year after 3~5. Most of such stainless steel pipes are still imported.
Stainless steel pipe for thermal power boilers
During the "11th Five-Year", the new thermal power is about 180 million kW, and about 40 million kW (600 thousand kW and above) each year, of which over 50% of the supercritical unit above (more heat resistant austenite steel boiler tubes are used). 1 stations and more than 600 thousand kW supercritical thermal power unit boiler need stainless steel heat resistant steel tube 200~500t, so according to the development plan, about 50 thousand T or more rust resistant steel pipes are needed each year. The domestic four major boilers are newly built 600 thousand kW sub critical and supercritical units and stainless steel heat resistant steel tubes for maintenance of power plants, all of them are choosing domestic suppliers. In addition, the domestic construction and maintenance of thermal power boiler for heat resistant steel tube consumption of about 12 thousand t/a, mainly involving TP304H, TP347H, TP321H three steel numbers, representing the size of the outer diameter 38~76mm, wall thickness 4~10mm, length more than 10m. Therefore, stainless steel heat resistant steel tubes for thermal power boilers are worth developing. As the requirements of the supercritical unit to high temperature and high pressure are raised, the demand for the TP347HFC, Super304H (1Cr18Ni-9Cu3N), and TP310HCbN (1Cr25Ni20NbN) of the advanced power plant boiler tubes will be increased. At present, all such stainless steel tubes are imported.
"Three" heat-resistant stainless steel tubes for industrial use
The heat resistant stainless steel pipe is mainly used for heat exchange and fluid transportation in the "three" industry. The market capacity is the largest and the domestic market demand is about 160 thousand T per year. The requirements for such steel pipes are very high and very strict. The potential market is a large caliber oil cracking furnace tube and low temperature pipe. Because of its special heat resistance and corrosion resistance requirements and equipment installation and maintenance inconvenience, the equipment needs a long service life cycle. It is necessary to optimize the mechanical properties and performance of the pipe through the material composition control and special heat treatment. Another potential market for fertilizer industry (urea and phosphate fertilizer) special-purpose steel pipe, the main types of steel are 316Lmod and 2RE69. At present, the above stainless steel tubes are basically imported.
Duplex (fluid, heat exchanger) stainless steel tube
Duplex stainless steel is mainly used in chemical industry and chemical fertilizer industry. Its main characteristics are stress corrosion resistance. The service temperature is below 350 C. Because of its high strength, stress resistance, corrosion resistance and economy, the market consumption of heat exchangers and fluid pipes has increased rapidly.
The heat-resistant stainless steel pipes are needed in the above fields. The main domestic production enterprises are Baoshan Iron Steel Co special steel branch, Zhejiang Yili Group Limited by Share Ltd, Panzhihua Steel Group the Great Wall Special Steel Co. Although some varieties have been developed successfully, they have not yet formed the capacity of mass production, they can not meet the domestic demand, and products need to be imported from abroad. The main production enterprises abroad include Sumitomo Sumitomo, Sweden SANDWICK, etc.