In this work, we demonstrate a methodology to perform Fitness-for-Service assessments (FFS) for various forms of stress corrosion cracking (SCC) as a function of temperature. Data were gathered from the literature to summarize crack growth rates in the different combinations of material and environment. Case study remaining life calculations were performed to provide a reference to quickly determine if a Level 3 FFS assessment would be a viable option given the damage mechanism, temperature, and time until repair could be made. Conservative crack growth rates for chloride SCC of stainless steel, caustic SCC of stainless steel, and caustic SCC of carbon steel were gathered for specific environments. At 160°F (71.1°C) and up to 33 ksi-in1/2 (36.3 MPa-m1/2), the crack growth rates are 0.033 inches/month (3.21 x 10-7 mm/sec), 0.240 inches/month (2.35 x 10-6 mm/sec), and 0.214 inches/month (2.10 x 10-6 mm/sec), respectively. These crack growth rates correspond to conservative remaining lives of 18 months, 2.5 months, and 2.1 months, respectively, for the pressure vessel geometry and initial flaw sizes that were evaluated. The analysis provides a methodology that can be extended to other materials and service conditions for which the necessary data are available.
Key words: stress corrosion cracking, fitness for service assessment, chloride stress corrosion cracking, caustic stress corrosion cracking, remaining life, fracture, standardization