The use of austenitic SS materials in the refining industry is selected to resist process side corrosion. These materials are considered key materials of construction for resisting severe high temperature corrosive conditions of sulfidation, hot hydrogen exposure and H2/H2S corrosion. Austenitic SS are successfully used in these applications because high temperature services are non-aqueous and hence trace amount of Cl - in many process streams can be tolerated. Experience has been gathered over many years in tropical environments with Cl - SCC from external surfaces of hot insulated equipment. This paper examines the conditions that promote external cracking and discusses several mitigation techniques.
Keywords: Austenitic SS, External Cl SCC, ESCC, Al Foil wrap