Weldments, intergranular corrosion

Its resistance to intergranular attack is excellent even when sensitized at 675°C for 1 h to simulate the heat-affected zone of heavy weldments. Material annealed at 1066°C has veiy good resistance to intergranular attack for most applications. However, when thick sections are used in the as-welded condition in certain strongly corrosive media, the 1121°C condition gives optimum corrosion resistance. 

A true ASME Section XI type inspection baseline does not exist for the SRS reactors due to the vintage of the plant and other limitations. Therefore, the data from each scheduled inspection will be analyzed to form an equivalent baseline. Examination methods and SRS categorization of weldments based on intergranular stress corrosion cracking (IGSCC) susceptibility are described in detail in Section III of the ISI plan. Inspection schedules, examination methods, frequency, and successive intervals for piping, heat exchangers, and reactor welds are described in the tables of the plan. (The-evaluation of reactor tank UT examinations, which are required for restart, is discussed below. 

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