Stainless Steel Square Tube And Special-shaped Tube

Stainless Steel Square Tube And Special-shaped Tube

Application of stainless steel pipe the main application field of stainless steel welded pipe is urban landscape and decoration engineering; in light industry, pharmacy, papermaking, sewage treatment, water supply, machinery and other fields, it also has a considerable proportion; in the chemical industry, chemical fertilizer, petrochemical industry and other industries, the medium and low pressure transmission pipeline with a specification of more than 159mm is generally selected; the automobile muffler also uses stainless steel welded pipe. Stainless steel seamless pipe is mainly used in the fields of chemical industry, chemical fertilizer and chemical fiber, petroleum, electric boiler, machinery, aerospace, nuclear industry, national defense industry, etc.

 

1、 Stainless steel pipe is used for oil drilling. Since 1990s, China's oil well pipe production capacity has increased year by year, the export volume is greater than the import volume, and the self-sufficiency rate has reached more than 90%. However, most of them are J55, N80 and other medium and low grade steel, and only a small amount of API high grade oil well pipes. At present, the API q125, C95, l80-2 (13Cr) steel grades with high strength, high CO2 resistance, CL corrosion resistance and high collapse resistance, as well as the special thread thread thread type not specified by API standard, as well as the oil well pipes used in cold areas, which are required by the oilfield, have not yet been industrialized. With the development of petroleum industry, more and more strict technical requirements are put forward for oil well pipes. The use of high performance and new materials is the technical development trend of oil well pipes. Stainless steel non-magnetic drill collar, super ferritic stainless steel Cr13 and Cr25 with high resistance to CO, CO2 and Cl - corrosion are all used in oil field drilling and production. According to rough statistical analysis, at present, it needs more than 10000 tons per year, and about 40000 to 50000 tons per year after three to five years. At present, most of these stainless steel tubes are still imported.

 

2、 Stainless steel tubes for thermal power boilers. During the 11th Five Year Plan period, about 180 million kw of thermal power will be added, and about 40 million kW (600000 kW and above units) will be added each year, of which more than 50% of the units above supercritical level (heat-resistant stainless austenitic steel boiler tubes are used more). A supercritical thermal power unit boiler above 600000 kW needs 200 ~ 500t stainless heat-resistant steel pipe, so according to the development plan, it needs more than 50000 t stainless heat-resistant steel pipe every year. Domestic suppliers tend to choose domestic suppliers for newly built 600 000 kW subcritical and supercritical units as well as stainless and heat-resistant steel pipes for power plant maintenance. In addition, the consumption of stainless and heat-resistant steel pipes for newly-built and maintained thermal power boilers in China is about 12000t / A, mainly involving three grades of TP304H, TP347H and tp321h. The representative specifications are outer diameter 38-76mm, wall thickness 4-10mm and length greater than 10m. Therefore, the stainless and heat-resistant steel pipe for thermal power boiler is worth developing. With the improvement of high temperature and high pressure requirements for supercritical units, the demand for advanced utility boiler tubes tp347hfc, Super304H (1cr18ni-9cu3n), tp310hcbn (1cr25ni20nbn) will increase. At present, all of these stainless steel pipes are imported.

 3、 Heat resistant stainless steel tubes for industrial use in Sanhua. Heat resistant stainless steel pipe is mainly used for heat exchange and fluid transportation in the "three chemical" industry, with the largest market capacity, and the domestic market demand is about 160000 tons per year. The requirements of users for this kind of steel pipe are very high and very strict, and they mainly rely on import at present. The potential market is the large-diameter oil cracking furnace pipe and low-temperature conveying pipe. Due to its special heat-resistant and corrosion-resistant requirements and inconvenient equipment installation and maintenance, the long service life of the equipment is required. Therefore, it is necessary to optimize the mechanical properties and service performance of the pipes through material composition control and special heat treatment methods. Another potential market is special steel pipe for chemical fertilizer industry (urea and phosphate fertilizer), the main steel types are 316lmod and 2RE69. At present, the above stainless steel pipes are basically imported.

 4、 Duplex (fluid, heat exchanger) stainless steel tubes. Duplex stainless steel is mainly used in chemical industry, chemical fertilizer and other industries. Its main characteristics are stress corrosion resistance and service temperature is lower than 350 ℃. Because of its high strength, stress resistance, corrosion resistance and economy, the market consumption of heat exchanger and fluid pipe is growing rapidly.