Hello Alice, Yes, the 3" casters will roll on carpet. But you may need a little more push if the carpet is thick. Home Depot also sells plastic mats for carpeting that make the wheels glide easier. Hope this helps. Good luck.
The video says they're polyurethane. On other sites Slipstick uses polyurethane interchangeably with "rubber". So for them polyurethane = rubber.
Using a tape measure the bracket that holds the wheel in place appears to be 1 and 5/16 inches wide. I hope this helps answer your question.
No, it is not recommended to be used on luxury vinyl.
No, it is not recommended to be used on mop buckets. They were designed for office chairs.
The wheel surface is a soft plastic material. I use it on carpet, but I believe that they would not harm a wooden floor.
The material on the circumference of the wheels is made of a soft plastic. I use them on carpet so I can't say for sure, but I believe that they would be reasonably quiet on a hard tile floor.
I use these caster wheels on a short-knap carpet, and they perform reasonably well. However I would recommend larger diameter wheels if you can find any which will attach properly to your chair legs.