核主泵静压轴封极限工况下运行可靠性研究

Operating Reliability Research of Hydrostatic Seals for ReactorCoolant Pumps Under Extreme Conditions

核电厂一回路主泵静压轴封现场运行期间,多次出现超出厂家运行技术要求的工况,由于缺乏主泵静压轴封运行参数影响机理研究,严重制约着轴封极限运行工况下的可靠性分析和评价。依托CPR1000核电机组100型核主泵双锥角静压轴封,提出一种流固耦合分析数值模型,系统阐述了极低压差、极限温度、内外锥角等关键因素对密封泄漏特性的影响机理。通过对极限工况运行可靠性进行研究,提出极限运行工况建议值,即压差不低于0.6 MPa,极限注入温度不高于100℃。可以为现场核主泵静压轴封极限工况下运行可靠性评价提供量化参考和指导。

The abnormal operating conditions of the hydrostatic seals in reactor coolant pumps were found several times,the analysis and evaluation could not be intensively investigated for the lack of the mechanism study of key influence factors.In this study,a hydro-elasto model was built based on the 100-type reactor coolant pumps of CPR1000 units to investigate influence mechanisms of the low pressure difference,high injection temperature,inner and outer cone angle.Based on the investigation of the extreme operating conditions,the operating suggestions was provided include the lowest pressure difference was 0.6 MPa and the highest injection temperature was 100℃,which could provide reference value for the operating of reactor coolant pumps on site.