There are several factors that impact ergonomics on an industrial cart or rack, casters are the most important part of that equation. The amount of push pull force exerted to start and continue rolling, as well as turn and maneuver are ergonomics issues that can be reduced by a well made ergonomics focused caster.
Of course, it all rides on the wheels, conventional thinking is the harder the wheel, the easier it is to push. While the hardness is does make it easier to roll, we do not suggest switching all your wheels to steel or phenolic, as this would cause several other issues.
First, will be the added noise. You will have carts that are easy to push , but also very loud, so loud that everyone in the plant will know when they are getting pushed.
Second, a phenolic or plastic wheel will accumulate debris in the rolling surface of the wheel. Debris accumulation occurs in the cleanest of factory environments. Debris is a fact of life. It exists. This requires a regular time commitment to replace these wheels. We all know our maintenance people’s time is much better served somewhere besides swapping caster wheels.
Third, the steel wheel will damage the floor. Plant managers are never excited about grooves carved in their beautiful manufacturing floors. This should never happen.
So now that the hard wheel is no longer an option, where do we turn? New polyurethane wheel tread formulations achieve a return of energy, hence reducing the amount of push pull force required.
Am I restricted in the size of my wheel? Can I take a 4 inch wheel and go to a 6 or 8 inch? Increasing the diameter
The diameter of the wheel impacts push pull force also. Larger diameter wheels result in much less effort to start, and an increase in momentum, to keep the wheel rolling. The width of the wheel however, has the opposite effect, the wider the wheel, the higher the amount initial and turning push force required. A wider wheel will create more surface pressure and make the wheel more resistant to switching directions.
The caster rigs can also have a significant impact on ergonomics, especially when turning, or starting rolling when all of the wheels are not parallel.
The longer the swivel lead (distance between the center of the swivel section and the center of the wheel), the easier it is to turn or start rolling when the wheels are not all parallel. Bearings in the swivel section also impact these activities, precision sealed ball bearings tend to require the least amount of force.