The operating condition of H2S stripping tower was simulation,the general corrosion,pitting corrosion and stress corrosion cracking sensitivity of 20#,304L,321 and 316L in wet H2S environment were evaluated by immersion corrosion test,potentiostatic anodic polarization method and U-bent specimen test.The results showed that the corrosion resistance of 20# steel was poor,and hydrogen blistering was easy to occure at low temperature.304L,321,316L austenitic stainless steels and 2205 duplex steel had a low corrosion rate and much better corrosion resistance.The pitting resistance of 304L and 321 stainless steels was a bit poor compared with 316L and 2205 steels,and honeycomb localized corrosion caused by slight pitting appeared.The existence of H2 S observably enhanced the pitting sensitivity of austenitic stainless steels in the environment containing Cl-.The welding samples of 304L,321 and 316L stainless steels had a good resistance to stress corrosion cracking.%模拟脱H2S汽提塔塔顶系统现场工况,采用浸泡腐蚀挂片、恒电位阳极极化法、U型弯曲应力腐蚀等方法对20号钢、304L、321、316L及2205不锈钢在湿硫化氢环境中的均匀腐蚀、点蚀和应力腐蚀开裂敏感性进行了研究,并利用体视显微镜和SEM对金属试样的微观腐蚀形貌进行了观察.结果表明:20号钢耐蚀性较差,易在低温下发生氢鼓泡,奥氏体不锈钢304L、321、316L及双相不锈钢2205的腐蚀速率较小,耐蚀性好,其中304L和321不锈钢耐点蚀性能稍差,表面出现了轻微点蚀造成的蜂窝状的局部腐蚀;H2S的存在明显提高了奥氏体不锈钢在Cl-环境中的点蚀敏感性;304L、321及316L不锈钢焊接试样均具有较好的耐应力腐蚀开裂性能.
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