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Single corrosive media environments, such as wet hydrogen sulfide stress corrosion problem has been extensively studied, there are a large number of research results been reported. But in the actual production, the corrosive medium wide variety of complex factors, especially in the petrochemical industry, its corrosive media involved such as hydrogen sulfide, chloride, carbonate, nitrate, often appear a variety of media coexist. That may arise based petrochemical plant H 2 S-CO 2 -H 2 O, CO-CO 2 -CO 3 2 - -H 2 O, H 2 S-CO 3 2 - -H 2 O and other types of corrosion, this paper H 2 S-CO 3 2 - -H 2 O due to stress corrosion cracking problem, with reference to the actual working environment of the hydrogen plant removal system, by slow strain rate test and wedge open loading pre-cracking test method in the laboratory to study the effects of temperature, carbonate and hydrogen sulfide concentration 16MnR steel stress corrosion cracking. Through the test, grasp the base metal and heat affected zone of 16MnR steel in the solution sensitivity to stress corrosion cracking and stress corrosion crack growth rate, anti-corrosion and provided the basis for the safety assessment of equipment in service, has important guiding production safety significance. The main findings are as follows: (1) In this paper, the Na 2 CO 3 H 2 S complex media environment, 16MnR steel base metal and heat affected zone materials stress corrosion susceptibility is not obvious, the fractography dimple. (2) 350 ppm H 2 S 5% Na 2 CO 3 complex media environment 16MnR steel base metal and heat affected zone materials in stress corrosion susceptibility of stress corrosion sensitivity slightly higher than room temperature 57.5 ℃. (3) stress corrosion susceptibility 2 S solution at room temperature, 16MnR steel of 200 ppm H higher than in the 200 ppm H 2 S 25% Na 2 the CO 3 solution stress corrosion susceptibility. (4) under the conditions of this research, the stress corrosion susceptibility of the heat affected zone and base metal materials relatively close. (5) With reference to the uniform design method at different temperatures (25 ℃, 57.5 ℃ and 90 ℃) and different concentrations of H 2 S (50 ppm, 200ppm and 350 ppm) and different concentrations of Na 2 CO 3 (5%, 15% and 25%) in a complex media environment, 16MnR steel base metal and heat affected zone materials the wedge open to load the pre-crack (WOL) the test, 16MnR steel in the above solution stress corrosion crack growth rate as 0.33 × 10 -8 mm / s ~ 4.31 × 10 -8 mm / s.
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