Will ball casters sufficiently support a "bookcase-door" (hinged from a front corner)?

Question

Followup to How do I know whether a bookcase will rack/sag/twist if hung using butt hinges as a (non-secret) "door"?

TL;DR:

1. I have a bookcase, want it to become a door, and load it with heavy stuff. (Not a secret one. Trying to keep it simple, even if ugly, as long as it's functional and strong.)
2. Didn't initially want wheels because it's above a clay tile floor, therefore not perfectly flat.
3. Bookcase being sufficiently internally supported depends on its backing plate or attaching the whole thing to an actual door.

Problem with point 3 is, the back isn't where it needs to hinge from, and offset hinges tend to be a lot weaker the more offset the pivot point is (no matter the style of hinge).

So my new question is:

If I use, say, 56 nylon ball casters, each rated to support 3kg static (or 5kg dynamic), will they durably support my bookcase (~135kg fully loaded, worst case scenario) given that heavy-duty butt hinges held by a 7.5"-square post will be there as backup?

Like these but smaller: https://www.amazon.com/Meoly-Transfer-Conveyor-Universal-Transmission%EF%BC%88CY-25B%EF%BC%89/dp/B06XH8T1CF

Answer 1

don't use casters, use fixed wheels. just point the axles of the wheels towards line of the the hinge pins and the wheels will be at the correct angle.

nylon will tend to collect grit which may damage the tile surface, ruibber may be a better choice.

Answer 2

56 nylon ball casters, each rated to support 3kg static (or 5kg dynamic), will they durably support my bookcase (~135kg fully loaded)

WOW, that would be quite a job installing 56 casters!

Instead I would use heavy duty casters. For example they are used on toolboxes and they can carry 300 kg each so you only need four of them plus the wheels can be large enough to overcome any floor issues.

They come in different sizes, just pay attention to the load capacity per caster, and you will need swivel type since you are rotating the book case in a half circle.

Additionally I would put the framing around the bottom part of the book shelf just above the floor to hide the casters.