When designing a cart or rack for manual material handling in an industrial application, casters are often an afterthought. Focus is usually on the safety of the contents and not the safety of the operator or people that come in the vicinity of the cart.
In actuality, casters could very well have the greatest impact on the performance and safety of the cart. Casters can have a significant impact on several safety factors. The most prevalent is ergonomics, the amount of energy exerted to start and keep rolling, as well as turn and maneuver. One study found that overexertion due to an outside force, costs US businesses of $15 Billion in 2012, that is the monetary costs including treatment and lost labor time, it does not account for the impact on morale in the facility. Ergonomic casters can help reduce push force and the risk of injuries due to overexertion.
Casters can also have a significant impact on noise, when a cart is shocked do to impact with an obstruction on the ground, the cart shakes causing its contents to shake as well, creating noise. In some cases, that noise can be extremely loud. Another cause of noise from a cart is flutter, this often occurs when the cart is used in a powered application like a tug train, the swivel casters shake rapidly because they do not have a long enough swivel lead.
Optional equipment on casters can also reduce the risk of injury,
• Toe guards protect workers from getting their feet caught under the wheel
• Brakes keep the cart from moving when loading and unloading, or unattended
• Swivel locks will keep the swivel section from rotating, allowing for greater control
We have also created a caster with a brake and a swivel lock integrated into one unit, it’s our Total Lock Brake. A single action engages or disengages both, the brake and the swivel lock. The pedal is mounted in a fixed position, so it is always accessible regardless the position of the swivel caster. It is also ergonomic, thanks to a foot controller pedal, operators do not have bend and risk straining their backs.
As you can see, those little wheels on the bottom of the cart play a big roll in safety.