Merrick Industrial Dolly 500 999 Lbs

Everything Casters

A caster is an assembly of wheel and mount. Casters make it easier to handle carts, dollies, racks and other heavy and/or bulky equipment. Casters are made from varying material, have different wheel diameter, tread width, and load capacity.

Things to consider when selecting casters:

• How heavy will the loads be?
• Will the working environment be slippery?
• Will there be exposure to corrosive chemicals?
• Will temperature range be a factor?
• Will there be exposure to corrosive chemicals?
• Will brakes be needed?
• What type of flooring will be in the environment?
• Is noise a concern?

In terms of maneuverability, there are either rigid or swivel casters.

• A rigid caster, fixed caster only rolls forward and backward.
• A swivel caster has a cylindrical portion that contains ball bearing tracks that allow the wheel to turn.

A kingpinless caster is a type of swivel caster that is not held together by a bolt or rivet. With kingpinless casters the stress of the load is distributed more evenly and so last longer than normal swivel casters. They are better at handling rough terrain, sharp turns and falls. Kingpinless casters initial cost more than other swivel casters.

Rigid or swivel casters are better in certain circumstances:

• The most common is 2 parallel swivel casters and 2 parallel fixed casters. For good turning and straight-line travel.
• With only swivel casters it is easy to move in any direction, useful for steering lighter loads around tight corners, but they are harder to control. Swivel locks on 2 of the casters can mimic the performance of the 2 swivel, 2 fixed caster arrangement.
• 4 rigid casters in a diamond shape is an inexpensive arrangement. In this configuration, the central pair are slightly taller than the front and back pair. The cart can then easily turn and pivot if the load is placed over the central casters.

Wheel Hardness
Rubber is softer than plastic, which is softer than metal. The hardness of specific casters is rated on three scales:

• The Shore A for softer rubbers.
• The Shore D for harder rubbers and plastics.
• The Brinell scale is used for metals, (BHN).
• Within the scales, higher numbers are harder materials.

Wheel Dimensions
The diameter is the height of the wheel. Total height of the caster includes the wheel and the mount. Wheels with greater diameter and width have lower starting and rolling resistance. They are for heavy loads and are quieter in use. Wheels with greater diameter create a higher center of gravity. A tall load can make for unstable maneuvering, and easier tipping.