基于可靠度理论的RBI修正模型研究

Research on the risk assessment method of risk-based inspection technology based on the reliability theory

基于风险的检测技术包括定性RBI判断和定量RBI计算,定性判断得到风险相对的高低,风险相对较低者则不必进行定量RBI计算,风险高者再进行下一步定量RBI计算。在API581中,国外风险分析统计表明,石化企业的风险分布范围有一个所谓的"二八"现象,即"80%的风险是由20%的设备引起",中高风险以上的设备范围一般在20%左右。但我国十套装置风险分析结果发现,这个结论在我国并不适用,我国中高风险设备往往在40%左右。论文分析了API581在中国应用的局限性,引入可靠度理论计算设备失效概率,预估未来的失效概率或可靠度,可以完整地以RBI方法在得知失效后果和失效概率下,评估出此设备在整个系统中所处的地位,从而适当地分配检测、维修资源,在RBI完成后再进行风险评价进而完成风险评估过程。

Risk-based Inspection（RBI）,includes qualitative RBI judgment and quantitative RBI calculation. Qualitative judgments give the relative level of risk,and the relatively low risk don＇t need for a quantitative RBI computing while is necessary for the high-risk. Foreign risk analysis shows that,as for API 581,there exists the influence of 80-20 rule in the risk distribution of petroleum enterprises which is interpreted as that 80% of risks are caused by 20% of equipments; the range of medium and high risks is about 20%. However,this conclusion is not so applicable in China after a comprehensive analysis was taken on ten sets of equipments as the medium-and high-risk equipments occupy about 40% of the total. By analyzing the limitations of the application of API 581 in China,the reliability theory was introduced to calculate the equipment failure probability,and to forecast future failure probability or reliability,which can completely evaluate the position of this equipment in the entire system by the consequences of failure and the failure probability,and thus appropriately allocate detecting,repair resources,then complete the risk assessment process.