辽河油田原油输送温度对管线钢内壁腐蚀行为的影响

为了探究高强度钢与低碳钢在原油输送过程中腐蚀性的差异,采用动电位极化和电化学阻抗技术,并结合金相显微镜,研究了辽河油田不同原油输送温度对X70钢和Q235钢电化学腐蚀行为的影响规律。结果表明:2种管线钢在原油中的极化曲线均呈活化溶解特性;当温度变化范围为40~70℃时,随着输油温度的升高,X70钢和Q235钢的腐蚀速率均增大,腐蚀现象越来越显著;相同温度条件下,X70钢的腐蚀速率明显低于Q235钢,X70钢在辽河油田原油中的耐蚀性优于Q235钢。

Effect of Delivery Temperature on Internal Corrosion Behavior of Pipeline Steel in Liaohe Oilfield

In order to explore the differences of corrosion between high strength steel and mild steel in the process of crude oil transportation,potentiodynamic polarization,electrochemical impedance spectroscopy (EIS) and metallographic microscope were utilized to study the influencing rule of different delivery temperature of the Liaohe oilfield crude oil on the electrochemical behaviors of X70 steel and Q235 steel.Results showed that the polarization curves of X70 and Q235 steel had typical characteristics of active dissolution in the crude oil.With the increase of oil temperature between 40 ℃ and 70 ℃,the corrosion rates of X70 steel and Q235 steel increased,and corrosion phenomenon became more and more significant.Under the condition of the same temperature,the corrosion rate of X70 pipeline steel was markedly lower than that of Q235 steel,and the X70 pipeline steel had better corrosion resistance than Q235 steel in the crude oil of the Liaohe oil field.