针对海底管线AUT分区法缺陷高度定量测量存在较大误差的情况，分析了分区法高度定量误差产生的原因，通过理论分析提出高度定量测量修正方法，通过试验对比分析，证明了高度定量修正方法的正确性及可靠性［1-4］，并得到第三方机构的认可。对于根部，表面及内部缺陷，通过此方法修正后，可使AUT分区法定量测量精度提高到1 mm以内，充分发挥了海底管线不同位置缺陷不同评定方法的优势，为今后海底管线铺设提供更好的质量保障。

The reasons that large quantitative errors existed in submarine pipeline AUT zone discrimination height sizing were analyzed through the theoretical analysis method and the height sizing quantitative correction methods were proposed. The accuracy and reliability of the correction method was verified, and received the third party acceptance. For root, surface and inter defects, AUT zone discrimination height sizing accuracy was improved to less than 1mm after adopting sizing correction and showed advantages of different location defects being with different evaluating methods. It can provide better quality assurance for future submarine pipeline laying.