Comparative analysis of failure probability for ethylene cracking furnace tube using Monte Carlo and API RBI technology

• Quantitative failure analysis for the ethylene cracking furnace tube was performed.
• Monte Carlo method and API Risk-Based Inspection (RBI) technology were used.
• Calculated probabilities of failure were compared.

Ethylene cracking furnace tube is one of the most critical components in the petrochemical industry to crack molecules at high temperature. The furnace tube degrades easily during operations which would cause equipment failure and lead to serious consequences, such as fire and explosion. In this work, a quantitative analysis of failure probability for the ethylene cracking furnace tube is performed using the Monte Carlo method and API Risk-Based Inspection (RBI) technology. The results have shown that the operation life of ethylene cracking furnace tube under interaction of creep and carburization is less than that under creep, and the failure probability calculated based on API RBI technology is lower than that using the Monte Carlo method. Moreover, the comparative analysis results prove further that creep and carburization are two main failure modes of the furnace tube rupture. Therefore, it is very necessary to provide reliable data to perform risk assessment and inspections on ethylene cracking furnace tube.