Abstract: Following API RP 581-2016 and GB/T 26610.4-2014, the failure probability of heat exchanger tube bundle is calculated based on Weibull probability and statistical analysis method, but the calculation process is quite different. Out of consideration for engineering application, the parameter selection of Weibull probability and statistical formula in GB/T 26610.4 is relatively simple, and there is no other parameter selection method as given in API RP 581. In this paper, two-parameter and three-parameter Weibull calculation models are used to calculate the failure probability of the heat exchanger tube bundles. Compared with the standard calculation results, it is found that the fitting degree of the calculation methods in GB/T 26610.4 is poor. Meanwhile, a method to determine the value of η parameter based on the design parameters is proposed and applied to the calculation of an example. The fitting degree of the method is close to the fitting degree obtained from the calculation method in GB/T 26610.4. And so this method can be used to calculate the failure probability of heat exchanger tube bundles.

Key words: failure probability, heat exchanger tube bundles, Weibull probability and statistical analysis method, fitting degree