试片断电法与管道阴极保护

通过对试片法及其断电测试测量的断电电位和IR降极端情况的分析,得出了试片法断电电位的分布区间,并认为对于3PE类型管道而言,管道最负通电电位不应负于-1.2 V.通过对试片法与恒电位仪同步中断法测试中＂防腐层破损点＂处所测结果物理意义的差异分析,认为试片断电电位可以等同于防腐层破损处裸露部位极化电位,其值能反映阴极保护水平,而恒电位仪同步中断法测得管道实际防腐层破损点正上方的断电电位与该处裸露部位极化电位存在差异,其值是长输管道断电整体效应的反映。通过对万用表测量试片断电电位时采样频率的分析,认为测试结果通常趋于保守。

Discussion about off Potential of Coupon and Cathodic Protection for Pipeline

After extreme conditions of off potentials and IR drop measured by coupons have been analyzed,the distribution interval of its off potentials has been obtained,and a conclusion also could be made that the on potenital especially for 3PE layer pipeline should not be more negative than- 1. 2 V. By means of comparing the different physical meanings of data measured by coupon and CIPS,a conclusion can be made that the off potential of coupons is almost the same as the polarized potential of bate metal at the coating broken place which can reflect the protection level,while the off potential of CIPS can not. The sampling frequency of multimeter indicates that the results of off potentials by coupons usually may be conservative.