湿气输送天然气管道腐蚀检测与安全性分析

Corrosion Detection of Wet Gas Pipeline and its Safety Analysis

为预测分析20号碳钢湿气输送天然气管道未来的腐蚀速率,选取了具有代表性的采气管段进行了极端情况下金属的损伤积累速度的腐蚀检测。结果表明,管道输气量和水气比是激化腐蚀的主导因素,指出腐蚀速率会随着输气量和水气比的增大而提高,在输气量和水气比相近的情况下,腐蚀速率随H2S含量增加而升高;在靠近焊缝的母材中H2S容易诱发氢致裂纹和脆化,并且随着天然气中H2S含量增加,氢致裂纹的倾向会加大。此外,受冲刷腐蚀的影响,弯管处的腐蚀速率较高。

To predict and analyze the future corrosion rate of wet gas pipeline(# 20 steel),the corrosion detection on accumulated corrosion rate of pipe metal in the extreme condition is made on 10 typical gas productivity gas pipelines.The results show that the gas transmission throughput and water/gas ratio are the leading factors to form corrosion.It is pointed out that the corrosion rate is developing with the growth of gas transmission throughput and water/gas ratio,and when the two is closed to each other,the corrosion rate is developing with the growth of H2S content.The H2S near the welds of base metal will result in HIC or embrittlement for the gas pipeline,and with the growth of H2S content in the gas,the trend of HIC will tend to be obvious.In addition,the corrosion rate in bending pipe will be high due to the erosion and corrosion.