Casters are used in numerous applications, including shopping carts, office chairs, toy wagons, hospital beds, and material handling equipment. High capacity, heavy duty casters are used in many industrial applications, such as platform trucks, carts, assemblies, and tow lines in plants. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship’s wheel, steering wheel, potter’s wheel, and flywheel.
It is a wonderful mobility enabler, with properties such as strength, corrosion resistance, water resistance, and weather resistance. The applications of caster wheels necessitate precise sizing based on the terrain on which they will be used and the weight they are expected to carry. A caster (also castor according to some dictionaries) is a wheeled device typically mounted to a larger object that enables relatively easy rolling movement of the object. Casters are essentially special housings that include a wheel, facilitating the installation of wheels on objects.
The purpose of this is to provide a degree of self-centering for the steering—the wheel casters around in order to trail behind the axis of steering. This makes a vehicle easier to control and improves its directional stability (reducing its tendency to wander). A castor wheel is a relatively small undriven wheel, meaning that it is free-rolling (as opposed to powered). They are designed to be attached to the bottom of a larger object, to enable easy movement across a floor or other hard surface. Castor wheels are often referred to simply by the standalone term ‘castors’.