关于SIL验证计算的探讨

STUDY ON SIL VERIFICATION CALCULATION

经HAZOP分析和SIL定级后,需验证安全仪表功能SIF回路是否满足SIL等级要求。其低要求操作模式时的失效概率PFD或高要求操作模式时的危险失效频率PFH,结构约束条件和系统能力应分别达到相应SIL等级的要求。文中给出了以上指标的计算方法和SIL判断标准,并结合规范要求,对SIL验证进行了深入的探讨。

After HAZOP analysis and SIL assessment,it is necessary to confirm whether the SIF loop satisfies the SIL requirements.If a specified SIL is achieved,the corresponding requirements for the probability of dangerous failure on demand(PFD)in low demand mode or the frequency of dangerous failure per hour(PFH)in high demand mode,the structural constraints and the system capabilities should be met,respectively.This article provides the calculation methods and SIL assessment criteria for the above indicators,and discusses in detail the SIL verification according to regulatory requirements.