If you have ever seen a caster wheel on its own, it might be shocking to think of how many different things use them. For something so small, simply, and seemingly insignificant, they have proven to be unbelievably useful. Of course, while they might seem to be designed the same and be made from the same materials, that could not be further from the truth. Since they are used for so many different things, it only makes sense they would come in all shapes and materials, each one especially designed for a specific purpose. If perhaps you are interested in learning any more, then continue reading:
Sizes
While smaller sizes are perhaps the most common sizes, including 4 inch caster wheels, it might shock you to know that they can actually get rather large. Some can even get as big as eight inches, though these are used for very specific items. Of course, the wheels are also measured by their width, though two inches seems to be one of the most common sizes.
Materials
Not only is the size of the wheel important, but the material itself also needs to be taken into consideration. They can be made of anything from polyurethane, phenol formaldehyde resin, thermoplastic rubber, or simple rubber. Furthermore, those materials are often actually just the outer portion of the wheel, sort of like a tire, and the inner wheel is sometimes composed of a different material. This portion can be made of cast iron, polyurethane with or without tread, or will be made from the same material as the outer portion.
Connection
How the wheel connects to whatever it needs to connect to also varies from wheel to wheel. All of them have a plate that allows you to bolt it to the item, but then that plate itself can either be rigid or be able to swivel. Then there are also various locking mechanisms that can be attached, allowing you to keep the object from moving or restrict specific wheels for moving. The lock itself can have different levels of locking, ranging from a full stop or just something that will slow it down.
Uses
As already mentioned, caster wheels can be found on an incredibly high number of objects, usually something used for more industrial needs. These items can be be toolboxes, six wheel carts, hand carts, chairs, shopping trolleys, and many, many more. There is a caster wheel out there for almost any need.