在4种管径管道内安装棒状辅助阳极，并通过外加电流对其进行阴极保护，利用自主设计的线型参比装置在实海试验中实时测量管道内部各点的阴极保护电位。并与Beasy软件模拟计算的阴极保护数据进行了比较。结果表明：在小管径管道中，随管径的减小，棒状辅助阳极轴向（单向）保护距离越短，当管径≤100 mm时，棒状辅助阳极轴向保护距离太短，不适宜用此种方式进行保护；模拟得到的棒状辅助阳极对DN200和DN125管道的轴向保护效果与实海试验结果相似，但管径≤100 mm时两种方式得到的结果出现较大偏差，说明此时管道实海测试受实际环境因素影响较大。

Impressed current cathodic protection was applied to the pipes with four kinds of diameters in which rod-shaped auxiliary anodes were installed. And a self-designed linear reference device was utilized to real-time measure the cathodic protection potentials of points in the interior of the pipes in real sea. And the experimental data were compared with the simulated data calculated by software named Beasy. The results show that in the small diameter pipes the axial protection distance (one way) of the rod-shaped auxiliary anode was shortened with the decrease of pipe diameter. When the pipe diameter was no more than 100 mm, the axial protection distance of the rod-shaped auxiliary anodes was too short to protect the pipe. The protection effects of rod-shaped auxiliary anode to DN200 and DN125 pipes obtained by simulation were similar to the results from real sea experiments. But these two results were quite different when the pipe diameter was no more than 100 mm, which means that in real sea environment small diameter pipe is affected critically by environmental factors.