I could see some offload ramps from the sawmill. ... A ramp to load logs onto my trailer. What would you use it for?
Any idea what the capacity of those are?
You may be able to fudge a bit if you make a continuous sheet of them, and mount it on heavy duty backing.
However, I wouldn't necessarily drop heavy stuff on them, and might limit myself to 500 to 1000 lbs or so of static load (using a bunch of them and generally distributed weight).
They are also probably designed for direct unidirectional movement. So, no heavy stuff sliding sideways.
Also, if you load not exactly straight pieces that are round, you may have very poor weight distribution, and may get all the weight resting on only a couple of rollers.
The last little piece of oak I loaded onto my trailer was probably somewhere around 3,000 to 5,000 lbs. Not something that I'd trust with rollers like that.
Anyway, this might be good for moving planks produced by a mill. Infeed/outfeed for a planer. Outfeed catch for your table saw. I'm planning on forming steel standing seam roofing, and bought a long roller for the outfeed of the forming machine.