针对海洋平台声发射无损检测的需求，通过研究同壁厚异径金属管声发射波传播特性，并与同厚度金属板中声发射波传播特性作一对比，得出异径金属管和板中传播特性规律及差异，揭示管径对声发射波传播特性影响。同壁厚管随着管径的增大，其声发射信号的峰值均呈衰减趋势。

For the requirements of offshore platform acoustic emission nondestructive testing, this paper obtains the propagation rules and differences of the metal pipes with different diameters and the differences with metal plate, reveals effects of the pipe diameter on propagation characteristics of acoustic emission waves, through the research on propagation characteristics of acoustic emission wave of metal pipes of the same wall thickness but with different diameters, comparison was made of propagation characteristics between the pipe and the plate taken as the limit case of the metal pipe. Pipe structures and plate structures are important parts of the offshore platform, so the research of this paper is of significant engineering application value to improve the positioning accuracy of fault sources and the analysis of fault characteristics in application of the offshore platform acoustic emission testing technology.