Akselos has released SPM for cokers, which assesses fatigue, bulging, and crack growth on the same model of a coke drum and reports remaining life for each mechanism separately. Refiners can now see which mechanism limits a drum’s life, and which cycles drive it, before deciding how to run the next one.
A delayed coker converts low-value vacuum residue into lighter, higher-value products by putting its drums through extreme thermal and mechanical stress. That stress accumulates unevenly: at Pan American Energy, 2.2% of coker cycles caused 83% of the drum damage.
Operations and integrity teams look at the same steel and ask two different questions of it. Operations asks how hard the drum can be run this cycle, tuning quench to protect the drum while holding production speed. Integrity asks how much life the drum has left, working from periodic inspection, which by design carries a margin for everything that could happen between scans. SPM for Cokers answers both questions from one structural twin, so both teams work from the same cycle-updated picture of the drum, and the margin integrity has been carrying becomes usable life.
The result is measured in deferred capital. Akselos modelling estimates that running a drum’s 100 highest-fatigue cycles differently can safely add around 8 years of drum life, worth roughly US$17 million in deferred capital on a pair of coke drums.
SPM for Cokers runs on a high-fidelity, fully parametric structural twin of the coke drum. After each cycle, that cycle’s operating data, such as temperatures, pressures and quench timing, is fed into the same model, so each assessment is based on how the drum was actually run. To establish the drum’s current condition, SPM first works through decades of its cycle history, tens of thousands of solves on a five-million-degree-of-freedom model. From that baseline, it runs one assessment per cycle at the same accuracy, covering fatigue per API 579-1 Part 14 Level 2, bulging and crack growth.
“Running a delayed coking unit is a constant balance between operations, process and integrity. Akselos brings these together by showing how the process affects the drum structure, where bulges, cracks and fatigue come from, and how much life remains. With one shared view, teams can find a way to shorten cycle times while extending drum life,” said Attila David, Director of Sales Engineering, Akselos.
Every damage mechanism that limits a coke drum’s life is now assessed on one model, on the same cadence the drum is actually operated. That gives refiners a basis for treating drum life as something managed cycle by cycle rather than estimated between inspections.
