Abstract: The interference corrosion of external steel structures located next to cathodically protected (CP) systems was evaluated based on electric field theory of stable currents.The parameters in the evaluation were from (1) peripheral electrical field modeling of CP systems,(2) location of external structures,and (3) polarization of the surface of metal structures.The equations of potential shift on structures were derived in typical cases,such as on pipes near the CP pipeline,or surface structures near the CP storage tanks or well casing.An example was given for a complex CP system.The interference potential and current density on pipeline near several CP storage tanks were calculated analytically,and the results were agreement those by numerical methods.

Key words: cathodic protection, interference corrosion, potential, current density, calculation

摘要： 采用稳流电场理论,根据阴极保护体系周围电场分布、受电干扰构件位置和构件表面电化学行为等参数计算阴极保护系统对外部金属构件的电干扰腐蚀.推导了阴极保护管道对外部平行或垂直管道,阴极保护储罐对地面管道和阴极保护套管对地面设施的电干扰电位公式.并以一个储罐区区域阴极保护体系对临近管道的电干扰为例,计算了干扰电位分布及简化条件下干扰电流密度(腐蚀速度),和国外文献中数值法计算结果吻合.解析计算法在工程应用和优化参数设计等方面有更大应用前景.

关键词: 阴极保护, 电干扰腐蚀, 电位, 电流密度, 计算