威布尔极值分布及其参数估计方法在储罐底板RBI计算中的应用  

Application of Weibull Extreme Value Distribution and Its Parameter Estimation Method in RBI Calculation of Tank Bottom Plate

作　　者：张子健 Zhang Zijian(Ningbo Labor Safety and Technology Services Co.,Ltd.,Ningbo,Zhejiang 315048,China)

机构地区：[1]宁波市劳动安全技术服务有限公司,浙江宁波315048

出　　处：《化工设备与管道》2024年第2期16-22,共7页Process Equipment & Piping

基　　金：宁波市重大科技任务攻关项目(2022Z165);宁波市公益类科技计划重点项目(2022S007)。

摘　　要：在常压储罐底板定量风险评估(RBI)过程中,底板腐蚀速率的选取会影响储罐整体风险等级的确定。基于威布尔极值分布理论,针对储罐边缘板,采用最佳线性无偏估计(BLUE)的方法计算了威布尔分布参数;针对储罐中幅板,采用简单线性无偏估计(GLUE)的方法计算了威布尔分布参数,随后通过线性回归理论分别计算了边缘板和中幅板的腐蚀速率,并将其赋予为腐蚀速率专家值对储罐底板进行了RBI计算。结果表明,威布尔极值分布理论计算可以科学合理地预估储罐底板腐蚀速率,边缘板的腐蚀速率为0.133 mm/a,中幅板的腐蚀速率为0.095 mm/a,与理论算法腐蚀速率的误差为3.6%,储罐底板风险等级为中高风险,在一定程度上解决了储罐RBI计算过程中腐蚀速率选取的难题,可为今后检验检测机构RBI的评估工作提供一定的技术支撑。In the quantitative risk assessment(RBI)process of atmospheric storage tank bottom plates,the selection of bottom plate corrosion rate will affect the determination of the overall risk level of the storage tank.Based on the Weibull extreme value distribution theory,the Weibull distribution parameters were calculated using the best linear unbiased estimation(BLUE)method for the edge plates of storage tanks;For the middle plate of the storage tank,the Weibull distribution parameters were calculated using the simple linear unbiased estimation(GLUE)method.Subsequently,the corrosion rates of the edge plate and the middle plate were calculated using linear regression theory,and they were assigned as expert values for corrosion rates to perform RBI calculations on the bottom plate of the storage tank.The results indicate that the Weibull extreme value distribution theory calculation can scientifically and reasonably estimate the corrosion rate of the tank bottom plate.The corrosion rate of the edge plate is 0.133 mm/a,and the corrosion rate of the middle plate is 0.095 mm/a.The error with the theoretical algorithm corrosion rate is 3.6%,and the risk level of the tank bottom plate is medium to high risk.This to some extent solves the problem of selecting the corrosion rate in the tank RBI calculation process,This can provide certain technical support for the evaluation work of RBI in future inspection and testing institutions.

关 键 词：常压储罐 风险评估 腐蚀速率 威布尔极值分布 最佳线性无偏估计 简单线性无偏估计 

分 类 号：TE988[石油与天然气工程—石油机械设备]