Civil transport aircraft?
Military aircraft are designed to significantly different specifications and requirements.
The 747 does not have any tiedown rings in the cargo floor. From our W&B manual which covers the 747 and 767:
The use of chains or other rigid devices for tie-down onto Company aircraft floor seat tracks is prohibited.
. . .
The use of chains for tiedowns is prohibited on Company aircraft.
. . .
The use of chains for tiedowns is prohibited on Company aircraft.
. . .
The use of chains for tiedowns is prohibited on Company aircraft.
I think that is quite clear.