海洋管道的涂层阴极剥离与阴极保护电流密度关系探讨

Discussion of Relationship between Cathodic Disbonding of Coating and Current Density of Cathodic Protection

本文从海洋管道的3LPE外防腐涂层和阴极保护的特点及相互关系出发,分析了阴极剥离产生机理及现行指标规定,开展了在一定温度下施加不同保护电流密度对试件涂层产生的阴极剥离影响的试验,采用阿伦尼斯模型和逆幂律模型进行了涂层失效寿命与阴极剥离指标的关系推导,给出了涂层一定设计寿命条件下采用的阴极保护电流密度的上限推荐值。

Starting from the characteristics of 3LPE external coating and cathodic protection for offshore pipeline, this article analyzes the mechanism of cathodic disbonding and required properties, carries out cathodic disbonding tests based on different cathodic protection current density applied on coated samples at certain temperature, then analyzes the relationship between coating failure life and index of cathodic protection using Arrhenius model and inverse power law model, and puts forward a recommended maximal cathodic protection current density for offshore pipeline at a certain design life of coating.