Someone may prove me wrong (not an unusual happening), but I don't think you are going to find a definite yes or no answer here or a Code "answer".
The Code simply states the circuit should be designed for the load and you have thrown in a lot of varibles. From "24 amps" we are now down to "no more than 20". The load is "not continuous", but it's seems almost impossible to determine how much would be concurrent.
From one standpoint, if you use a 225 amp feeder, properly protected, worse electrical scenerio, the breaker trips.
But, you also state the equipment is "essential to the operation", so you might not want to take the chance.
My experience with industrial would be that normally you would provide two panels or a larger panel, but that's based on my experience only.
In most industrial applications, loads are usually added periodically, so "overkill" can also be seen a "planning"