Probabilistic Life Prediction for Crack Initiation on Coke Drums Based on Monte Carlo Simulation

High thermal stresses developed in coke drums can lead to fatigue crack initiation and subsequently growth until premature drum failure. To predict the fatigue crack initiation lives of coke drums, a cost-efficient method was proposed using Monte Carlo simulation in this paper. Strain data on the critical location of the drum wall was collected through the field measurement. Then statistical analysis was performed to build the probabilistic model of strain amplitude distribution. Large number of strain data could be generated by sampling on the basis of the probabilistic model. The fatigue crack initiation life was calculated according to Manson-Coffin equation and Palmgren-Miner's cumulative damage rule. The crack initiation was predicted probabilistically and the predicting result was in good agreement with the inspection history. The method developed in the present study is expected to be helpful for the future maintenance and inspection of coke drums.