Four corrosion resistant alloys (G, 28, 2205, 825) were evaluated to determine their resistance to corrosion, pitting and stress corrosion cracking. Evaluations consisted of exposing test specimens to a simulated service environment and to a simulated acidizing environment. In the acidizing experiment, alloy G, 825 and 28 gave acceptable performance with alloy G having the best resistance to corrosion and cracking. In the
simulated service environment, all of the four materials tested showed evidence of susceptibility to pitting. It was concluded that additional testing was required to find an acceptable material.
Electrochemical tests were conducted on four alloys (G, C-276, 718, 625) to determine their pitting resistance in sample brine from the injection well unit. Alloys C-276 and 625 exhibited acceptable performance. In addition, alloy C-276 was tested for cracking susceptibility using the slow strain rate test and found to be resistant.
Based on the data accumulated, it was concluded that alloy C-276 was the material of choice for use as production tubing and that alloy 625 would be acceptable for use as the wellhead cladding material.
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