Solving brewery stress corrosion cracking problems.
The austenitic stainless steel Types 304 and 316 are most frequently used for solving corrosion problems as they have excellent general corrosion resistance, good pitting and crevice corrosion resistance and are easy to fabricate and weld. The corrosion resistance of the two types are compared. However, both are susceptible to chloride stress corrosion cracking (SCC) and two new grades of steel, Type 444 ferritic stainless steel and Alloy 2205 duplex stainless steel have recently been developed with are resistant to SCC. The corrosion resistance to both these new steels is discussed in detail. Examples of the use of Type 444 in sausage manufacturing equipment, pressure cookers, hot water tanks and heaters are described. In the brewing industry Type 444 has replaced 304 in liquid adjunct lines and in hot water tanks which suffered SCC failures.
Keywords: brewery chlorides corrosion corrosion prevention organic acid stainless steel stress corrosion