Kingpin casters are often categorized according to their swivel assembly. All kingpin casters have a swivel assembly. It’s a collection of components that allow the connected wheels to swivel in all directions. The swivel assembly, however, may contain a single ball race or a double ball race. If you’re thinking about buying a kingpin caster, you should familiarize yourself with the differences between these two race types.
What Is a Single Ball Race?
A single ball race is a ring of ball bearings that run along the top of a kingpin caster. Kingpin casters rely on ball bearings to provide a swiveling action. With ball bearings, they can turn and swivel. The ball bearings must be contained, though, so that they don’t fall out of the assembly.
A race is an enclosure for the ball bearings. It contains the ball bearings while providing the with a track on which to roll. The ball bearing will roll along the track inside of the race, thus allowing the kingpin caster to swivel. A single ball race simply means that the kingpin caster has a single ring-shaped track of ball bearings.
What Is a Double Ball Race?
A double ball race, as you may have guessed, is a set of two ball bearing rings. There are kingpin casters with a single ball race, and there are kingpin casters with a double ball race. Those with a double ball race have two ball bearing rings.
The upper ball race absorbs direct thrust, whereas the lower ball race encompasses the kingpin while subsequently absorbing lateral thrust. Double ball race kingpin casters are similar to single ball race kingpin casters, but they have two ball races instead of one.
Choosing Between a Single Ball and Double Ball Race
Most kingpin casters have either a single ball race or a double ball race. Double ball race kingpin casters have twice as many ring-shaped tracks of ball bearings. They have an upper ball race and a lower ball race.
Single ball race kingpin casters typically cost less than those with a double ball race. They feature a simpler design consisting of fewer parts. As a result, single ball race kingpin casters usually cost less than double ball race kingpin casters.
Double ball race kingpin casters, on the other hand, roll more smoothly than those with a single ball race. Each of the two ball races helps to absorb thrust. The end result is smoother rolling.