With the introduction of the country's policy for adjusting the power structure and prioritizing the development of clean energy, the growth of thermal power generation installed capacity has slowed down, and thermal power generators have also taken the road of efficiency and cleanness at the same time. In the emission reduction and efficiency improvement of thermal power generation, the use of supercritical units and ultra-supercritical units has increased. The supercritical (ultra-supercritical) unit improves the thermal efficiency of the unit by increasing the pressure and temperature of the steam in the boiler. Its steam and water pipes include reheater tubes, superheater tubes, water-cooled wall tubes, economizer tubes, air preheating tubes, heat transfer tubes, downcomers and various header tubes, which are under the conditions of high temperature and high pressure for a long time. Therefore,tubes shall have high durability, high resistance to oxidation and corrosion, and good structure stability. Generally, the supercritical (ultra-supercritical) unit consumes about 1,250 tons of high-pressure boiler tubes such as Super304H and HR3C per million kilowatts.
With the development of supercritical (ultra-supercritical) units, the temperature and pressure of boilers are getting higher and higher, the working environment of tubes is becoming more and more severe, the size of tube is increasing, and the demand for high-end stainless steel boiler tube is also increasing.
Wujin Stainless, as the first domestic supplier of S30432 in the boiler industry, has been supplying the largest number of ultra-supercritical units in these years. Among them, No. 3 660MW ultra-supercritical unit of Henan Datang Xinyang Power Generation Co., Ltd. is the first ultra-supercritical unit using domestic S30432 stainless steel seamless tubes.
Since there had been no stainless steel seamless pipe for boilers of ultra-supercritical thermal power units in China, Wujin Stainless has made independent innovation, and formed core technologies and products with independent intellectual property rights. It has successively passed the scientific and technological achievements appraisal by China Machinery Industry Federation, China Standardization Committee on Boilers and Pressure Vessels, and Chinese Society for Electrical Engineering. The products have reached the advanced level compared with similar products in foreign countries, substituting imported tubes and filling domestic gaps.