花-格管线腐蚀穿孔失效模型分析

为了寻找花 -格管线腐蚀穿孔的原因 ,对西起柴达木盆地西部的油沙山 ,东至其东部格尔木 ,全长 435.7km的花 -格管线运行以来的腐蚀穿孔次数进行统计分析和相关性计算 ,得出腐蚀穿孔累积数对数和运行时间的线性关系、腐蚀穿孔累积数和运行时间的指数关系 .模型表明腐蚀穿孔失效呈加速态势 ,其腐蚀失效机理是管道防腐层下电屏蔽的电化学自催化腐蚀和管道保温层中干湿交界处氧浓差腐蚀 .

Buried Pipeline Corrosion Punching Failure Model

Corrosion punching hole is a main failure way of buried pipeline. According to the statistic data of the number of the corrosive holes in the buried pipeline from Youshashan to Geermu in Chaidamu Basin, it is known that the relationship is linear between the logarithm of the number and service time. The exponent relationship was also obtained between the number and the service time. It is held that the corrosion punching hole is caused from the autocatalyzed electrochemical corrosion of the electric shield under the anticorrosion layer of the pipeline, and the oxygen concentration corrosion of insulating layer at dry wet boundary. The mechanisms of the two kinds of corrosion were analyzed.