The process industries utilize a wide range of feeds and process chemical in their production. Thus, equipment and components are exposed to a wide variety of often aggressive environments. The advantages of a material that offers resistance to many differing media are obvious. In the past, only nickel-chromium-molybdenum corrosion-resistant alloys (CRA’s) such as grades 625, 22 and C- 276 have offered this sort of versatility. However, an advanced grade of super-austenitic stainless steel (UNS S31277 ... alloy 27-7MO) that offers resistance to a wide variety of media is available. With a reduced content of nickel, it offers a significant economic advantage over nickel-base CRA’s. In addition, its mechanical properties are enhanced by its content of nitrogen such that it offers strength advantages as well. The stainless steel’s excellent corrosion resistance is evident by its high PREN value. It is also shown that the alloy offers excellent resistance to the common process acids including hydrochloric, sulfuric and phosphoric as well as oxidizing salts such as ferric and cupric chloride. As the alloy is readily fabricated by conventional techniques, it is an excellent candidate for a variety of applications in the chemical, petrochemical, mining, oil and gas, and refining industries.
Key Words: Stainless Steel, Nickel Alloy, Super-Austenitic, Corrosion, Fabrication, Seawater, Marine, Chemical Processing, Welding, Molybdenum, Pitting, Crevice Corrosion