Marc – We have used a hanging scaffold for top head inspection and repair at our Chalmetter Refinery. I can send you that drawing.
In the Fluid & Flexi Cokers, a number of units use an expandable scaffold referred to as a “swing stage”. It can expand in diameter and it is motorized so it can be automatically raised and lowered to gain access to the entire reactor. This has been used for a number of years at the Syncrude and Sarnia Fluid Cokers. The challenge will be the smaller access in Delayed Cokers – smaller manways to work from. It may be possible to enter with the core of a swing stage at the bottom head opening and then expand once the core is in the drum. Perhaps the swing stage can then be supported and motorized up and down from the top head to give full access to the entire drum and to allow work to be conducted, if needed. I can send you a sketch of the concept.
Regards – Mitch