This is an age old subject that most cokers experience if making transition or shot coke. I know of a coker that had not an explosion in 40yrs – they made anode grade coke- they had an explosion and severe injury when the drum erupted out the top and an employee was up there.
Beware – it can happen to any drum and all types of coke.
The best you can do is to protect your employees with proper unheading devices and…….
there are indications you can look for.
Examples are given in previous coking.com responses you can look up. Watching/measuring the amount of water you are putting in is one indicator. Watching temperature profiles on the drum is another if you have the data.
I would particular watch all drum indications when you have changed feed as some will quench better than others. Any unusual situations filling the drum should be a warning that the drum may drill differently. If the drum has some hot spots consider draining and refilling the drum before starting drilling operations.