One of the most common failure mechanisms of a coke drum shell is the bulging and cracking of the cylindrical pressure boundary.
These failures are typically aligned with the circumferential welds, with similar failures appearing in vertical plate “seamless” vessels designs as well.
In addition to bulging and cracking, localized crack repair and emergent bridge repairs have become more commonplace.
Other common failure mechanisms are associated with support skirts and their associated attachment welds, such as skirt repair geometries, skirt attachment zone base metal repair, and sectional skirt partial replacement.
Coker vessel skirt attachment geometries vary by designer and age of the vessel with the attachment point a common source of failure, making the design and implementation of the repair complex.
