Throughout the refining industry, there is a need to increase the return on investment of aging assets. Remaining life technology application and development is widely adopted to increase value from existing infrastructure and equipment. In this paper, an innovative way of continuing to utilize compromised vessels was creatively pursued. The technique and principles can be applied to vessels or equipment that is known to have shape deficiencies without having to replace sections, components, whole shells, drums, towers or casings. In this way, the costly rebuild work and greater loss of production can be avoided. Replacement was circumvented in a Delayed Coking Unit (DCU) for a Canadian oilsands upgrader.
In this case study, principles were taken from the building transportation and moving industry and applied to lifting and tilting of 145ft (44.2m) high coke drums. The ability to tilt and re-align a vessel of 14 storey (equivalent height) thin shell coke drum was believed to be possible and was subsequently performed successfully, at this location, multiple times. These were the largest coke drums in the world (at the date of their fabrication in 2006). The design and engineering issues are discussed in detail, including the techniques and analysis, stability, protection against buckling and finally; inspection and verification.