城镇杂散电流对天然气管道腐蚀行为的研究  

STUDY ON CORROSION BEHAVIOR OF NAT-URAL GAS PIPELINE BY STRAY CURRENT IN TOWN

作　　者：陈丽 Chen Li(Safety and Environmental Protection Tech-nology Supervision Center of Liaohe Oilfield,Panjin,Liaoning,124011)

机构地区：[1]辽河油田安全环保技术监督中心,辽宁盘锦124011

出　　处：《石油化工安全环保技术》2024年第3期25-28,I0002,共5页Petrochemical Safety and Environmental Protection Technology

摘　　要：城镇杂散电流是引起埋地天然气管道腐蚀的关键因素。本文基于现场地铁运行下埋地管线管地电位监测结果,通过电化学实验和腐蚀形貌分析研究了不同直流干扰条件(阳极干扰、阴极干扰、动态干扰、阴保状态)下X65钢的腐蚀行为,结果表明,与阳极干扰和动态干扰相比,无干扰和阴极干扰条件下X65钢腐蚀电位较负,腐蚀电流密度较小,说明此时X65钢腐蚀速率较小;而动态干扰下金属腐蚀速率略大于阳极干扰,此时金属表面在正、负电位交替变化过程中,表现为严重的点蚀特征。Stray current in town is the key factor that causes corrosion in buried natural gas pipeline.In this paper,based on the monitoring results of underground pipeline potential under the operation of the subway,the corrosion behavior of X65 steel under different DC interference conditions including anode interference,cathode interference,dynamic interference and cathodic protection was studied by electrochemical experiments and corrosion morphology analysis.The results showed that compared with the anode interference and dynamic interference,the corrosion potential of X65 steel was negative and the corrosion current density was smaller under the conditions of no interference and cathode interference.This indicated that the corrosion rate of X65 steel was smaller.Under dynamic interference,the corrosion rate of metal was slightly higher than that of anode interference.In this case,the metal surface was in the alternating process of positive-negative potentials,presenting serious pitting characteristics.

关 键 词：直流杂散电流 X65钢 动态干扰 电化学 

分 类 号：TE988.2[石油与天然气工程—石油机械设备]