针对无缺陷管道极限状态方程，识别出影响管道安全的关键参数为压力、管材强度及壁厚。研究分析管道失效概率对压力、管材强度和壁厚参数的敏感性，得到敏感性排序为压力平均值>管材强度标准差>管材强度平均值>壁厚平均值>压力标准差>壁厚标准差。以某管径1 219 mm、钢级L555、设计输送压力10 MPa的天然气管道为例，研究发现设计工况下，不同地区等级内的高后果区管段采用0.5设计系数对应的壁厚时，能够保证各管段具有相同的安全水平。然而，与设计工况相比，强度试压时管道屈服失效概率增大100倍以上，存在破裂失效风险，二者均超过允许失效概率。研究提出两种降低其失效概率的措施：一是全线使用0.4设计系数对应的管材壁厚；二是提高管材屈服强度和抗拉强度参数，即屈服强度平均值由555 MPa提高至600 MPa，抗拉强度由625 MPa提高至688 MPa，并合理控制生产参数的波动范围。

This study focused on the limit state equation for defect-free pipelines, identifying key parameters affecting pipeline safety such as pressure, pipe strength, and wall thickness. A sensitivity analysis of pipeline failure probability with respect to these parameters revealed the following ranking: mean pressure > standard deviation of pipe strength > mean pipe strength > mean wall thickness > standard deviation of pressure > standard deviation of wall thickness. Taking a natural gas pipeline (1 219 mm, L555 steel grade, 10 MPa) as an example, the study found that adopting a 0.5 design factor for wall thickness in high-consequence areas (HCAs) across different regional classifications ensured uniform safety levels under design conditions. However, during strength pressure testing, the yield failure probability increased by over 100 times compared to design conditions, exceeding allowable thresholds and posing rupture risks. To mitigate this failure probability, two solutions were proposed: first, using a 0.4 design factor for wall thickness along the entire line, and second, increasing the mean yield strength from 555 MPa to 600 MPa and the tensile strength from 625 MPa to 688 MPa, while tightening manufacturing parameter tolerances to reduce variability.