冗余安全系统的可靠性分析

The Analysis of the Redundant Safety System Reliability

在石油化工生产中,安全保护系统担负着生产过程中发现、识别、确认生产事故隐患,作出必要的反应、保障生产安全的任务。安全保护系统冗余配置是石油化工生产系统安全保护的常见形式。以可靠性理论为基础,建立了单元或冗余配置安全系统的可用度和故障率计算模型。以此模型对实践中的单元和冗余配置系统进行的比较和分析,认为系统冗余配置时,无论是并联组合还是串联组合,安全系统的可用度都是增加的,但同时显性故障有所增加,隐性故障大大减少;同时,从安全上考虑,采用ESD与DCS串联方式的系统将使安全保护的范围相应增加,同时安全系统的可用度有所上升,生产过程的安全状况明显改善。因此注意补充安全保护功能而不是简单的重复其功能,这对提高系统的整体安全效果将是明显的。

Safety system is the important unit in petrochemical process, which shoulders the responsibility of detection, identification, confirmation of the hidden troubles, quick reaction and safety ensurance. Redundant unit is a familiar type in the safety system. Based on the reliability theory, the parallel and series modal of unit or redundant system was set up, and the DCS & ESD mixed system was compared and analyzed. The availability of redundant system is enhancied no matter it is parallel or in series, but the initiating failure also increases and inhibiting failure decreases, it is therefore proposed that the supplement of safety protection but not its simple repetition should be cared. The effect can greatly improve its integrity level of safety system.