1. Sulfuric acid: As one of the strong corrosive media, sulfuric acid is a major industrial raw material that is very common. Sulfuric acid with different concentration and temperature has a great difference in the corrosion of the data. For concentrated sulfuric acid with a concentration above 80% and temperature less than 80 °C, carbon steel and cast iron have good corrosion resistance, but it is not suitable for high-speed active sulfuric acid. It is not used as a pump valve; the choice of 304 stainless steel (such as 0Cr18Ni9) and 316 (0Cr18Ni12Mo2Ti) for stainless steel valves is also limited. The pump valve for conveying sulfuric acid is made of high-silicon cast iron (difficult forging and processing) and high-alloy stainless steel (20 alloy). Fluoroplastics have better resistance to sulfuric acid, and the use of fluorine-lined valves is a more economical option.
2, acetic acid: It is one of the most corrosive materials in organic acids, popular steel in all concentrations and temperatures of acetic acid in the city (huì) severely corrupted, stainless steel is excellent resistance to acetic acid, 316 stainless steel valves containing molybdenum Can be used for high temperature and succinct acetic acid vapor. High-alloy stainless steel valves or fluoroplastic valves are available for high-temperature, high-concentration acetic acid or other erosive media.
3. Hydrochloric acid: Most of the metal materials are not resistant to hydrochloric acid corrosion (including various types of stainless steel data), and molybdenum-containing high silicon iron can only be used for 50 ° C, 30% hydrochloric acid. Contrary to metal data, most non-metallic materials have excellent corrosion resistance to hydrochloric acid, so rubber valves and plastic valves (such as polypropylene (C3H6), fluoroplastics, etc.) are the best choice for transporting hydrochloric acid.
4. Nitric acid: Most metals are mostly aggravated and damaged in nitric acid. Stainless steel valves are the most widely used nitric acid-resistant materials. They have excellent corrosion resistance to all concentrations of nitric acid at normal temperature. It is worth mentioning that they contain molybdenum-containing stainless steel. (such as 316, 316L) corrosion resistance to nitric acid is not only better than ordinary stainless steel (such as 304, 321), and sometimes even worse. For high-temperature nitric acid, all materials are taken from titanium and titanium alloys.
