You can’t ignore the bearing type when choosing casters. Whether stem or top plate, all casters have a bearing. The bearing is the assembly that connects the wheel to the axle.
Without a bearing, there wouldn’t be anything to hold the wheel to the axle. Bearings are assemblies that provide this connection. Here are some of the most common types of wheel bearings for casters.
One of the most common types of bearings for casters is plain. Plain bearings consist of a smooth bearing surface. They don’t contain any balls or rolling elements. Plain bearings are simple and use a basic design consisting entirely of a bearing surface.
Some casters feature a ball bearing. Ball bearings live up to their namesake by leveraging balls. They consist of round and smooth balls on a track. Ball bearings are highly effective at reducing friction, making them a popular choice for casters.
Friction is a form of restriction. The more friction to which a caster is exposed, the harder it will be to roll the caster. Casters that use a ball bearing, though, are easy to roll. Ball bearings minimize friction so that the casters are easy to roll.
There are also roller bearings. Many people assume that roller bearings are the same as ball bearings, but this isn’t the case. Ball bearings contain spherical balls, whereas roller bearings contain cylindrical rollers.
Ball bearings are better suited for light loads. If you’re planning to use a set of casters on a heavy object, you should go with roller bearings. The cylindrical rollers can accommodate heavier loads.
Sintered iron bearings are characterized by their powder-coated design. Sintered iron is iron that’s been coated with small powder particles. A process known as sintering, it protects the iron from corrosion. The powder particles will form a shell over the iron so that moisture or contaminants can’t reach the iron.
Sintered iron bearings are made of sintered iron. They are also oil-impregnated. The oil creates a smoother bearing surface by reducing friction.
Not all casters feature the same type of bearing. Casters consist of undriven wheels with a frame, and they are designed for use on the bottom of an object. Some of them have a different type of bearing for the wheel than others. There are plain bearings, ball bearings, roller bearings and sintered iron bearings.