在重水堆运行工况下Zr-2.5Nb压力管会通过腐蚀吸收重水中的氢（或氘）。若压力管中的吸氘量超出限值，会增加压力管的氢化破裂风险。分析了国内某重水堆机组压力管氢当量浓度的历次在役检查结果，确认管体部分主要以吸氘为主，且从压力管的入口端到出口端氢当量浓度逐渐增加。该压力管的吸氘量显著小于设计参考电站同期压力管的。根据Arrhenius关系式对压力管管体进行吸氢建模，通过拟合可分别获得2台机组的模型参数，其具有适当的保守性，可用以计算未来压力管管体氢当量浓度的预测上限。结果表明，压力管管体吸氢量（氢当量浓度）在210 kEFPH下仍远低于氢化物溶解极限固溶度，吸氢速率也显著小于标准规定限值，因此可认为这将不会成为压力管道运行的限制因素。

Zr-2.5Nb pressure tubes would take in hydrogen (or deuterium) under heavy water operating conditions. Once the hydroge uptake exceeded the corresponding limit, it would have a negative impact on delayed hydride cracking for the pressure tubes. In-service inspection data for pressure tube body hydrogen equivalent concentration was analyzed and it was noted that the concentration for each fuel channel increased along the axial from inlet to outlet. A hydrogen absorption model according to Arrhenius relationship was developed based on the fact of deuterium being the major concern of pressure tube body hydrogen uptake. The deuterium concentration of the pressure tube body was lower than that observed in design-referred plant. According to the modeling results for upper prediction limit of hydrogen uptake, the hydrogen equivalent concentration of pressure tube body would still keep far from the terminal solid solubility of hydrogen for dissolution at 210 kEFPH while the deuterium uptake rate would keep below the standard limit thus it would not be a concern for life extension of pressure tube.