904L super austenitic stainless steel is a low carbon high nickel, molybdenum austenitic stainless steel acid, proprietary materials introduced into France H? Company S. Has a good active - passive conversion capability, excellent corrosion resistance, has good corrosion resistance in a non-oxidizing acid such as sulfur Suan, acetic acid, formic acid, phosphoric acid, in neutral chlorine ions medium has a very good pitting resistance, also has good resistance to crevice corrosion and stress corrosion resistance. Applicable to various concentrations of sulfur below 70 ℃ suan, resistant to any concentration under atmospheric pressure, any temperature of acetic acid and formic acid and acetic acid mixture in the corrosion resistance is also very good. 20Cr-24Ni-4.3Mo-1.5Cu grades and standards: UNS N08904, DIN1.4539 ASTM A240 (new standard will be classified as stainless steel series, the original standard ASME SB-625 be classified as a series of nickel-based alloys), SUS890L . * Petroleum, petrochemical equipment, such as petrochemical equipment in the reactor. And so on. * The power plant flue gas desulfurization unit, the main use parts: the absorption tower, flue, file door trim, sprinkler system. * Organic acid processing system in the scrubber and the fan. * The seawater processing device, seawater heat exchanger, the paper industry equipment, sulfur suan, * equipment, acid, pharmaceutical industry and other chemical equipment, pressure vessels, food equipment. * Pharmaceutical Factory: centrifuges, the reactor, etc.. * Plant food: cans of soy sauce, cooking wine, salt shaker, equipment and dressings.