基于海底管道机械测径和水压试验在海管工程建设中的重要意义，重点梳理了ASME、 API与DNV标准对海管机械测径和系统水压试验的要求。通过阐释海管机械测径的原理，分析了不同标准下测径板直径计算方法。基于海管压力试验原理，明确了测试压力和稳压时间是海管试压中的两个关键参数。压力试验值的大小取决于压力试验中需要检查出的缺陷大小。稳压时间的长短影响因素较多，主要包括泄漏点大小、海管容积、海管直径等。虽ASME、 API与DNV在海管试压方面的总体原则基本一致，但在测试压力和稳压时间的选取上存在不同，工程实践中需分析其适用性。

Given the significant importance of mechanical gauging and pressure testing for submarine pipelines in offshore pipeline construction， this study focuses on reviewing the requirements for mechanical gauging and system pressure testing as outlined in the ASME， API， and DNV standards. By explaining the principles of submarine pipeline mechanical gauging， the calculation methods for gauge-plate diameters under different standards are analyzed. Based on the principles of pipeline pressure testing， it is clarified that test pressure and holding time are the two critical parameters in pipeline pressure testing. The magnitude of the test pressure depends on the size of the defects that need to be detected during the test. The duration of holding time is influenced by multiple factors， including the size of leaks， pipeline volume， and pipeline diameter. Although ASME， API， and DNV share similar general principles for submarine pipeline pressure testing， differences exist in the selection of test pressure and holding time， which necessitates an analysis of their applicability in engineering practice.