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The 904L flange is a pipe fitting made from 904L ultra-low carbon austenitic stainless steel, and its key features are its excellent corrosion resistance and high strength. Material 904L contains 19-23% chromium (Cr), 23-28% nickel (Ni), and 4-5% molybdenum (Mo); the addition of copper (Cu) in an amount of 1-2% further enhances its resistance to pitting and crevice corrosion, making it particularly suitable for harsh operating conditions such as those involving strong acids and chloride ions. From a manufacturing perspective, 904L flanges are typically produced using forging processes, during which high pressure is applied to refine the metal grains, eliminate internal defects, and improve the density of the material. After forging, solution treatment is required (holding at 1050–1150°C followed by rapid cooling) to stabilize the austenite structure, ensuring that the flange maintains toughness in both low- and high-temperature environments. Its execution standards include the internationally recognized ASME B16.5 and the domestic standard GB/T9119-2010, etc. The nominal diameter range spans from DN15 to DN900, with pressure ratings up to PN25. The sealing surface type is mainly RF (raised face), making it suitable for various pipeline systems. In terms of application areas, 904L flanges are widely used in the petrochemical industry (such as in sulfuric acid and phosphoric acid production facilities), offshore engineering (seawater desalination equipment), and the power industry (wet flue gas desulfurization systems). Contact: Manager Wang, 15076801731