While all-purpose casters are useful for general applications, sometimes the nature of your load requires more specialized wheels. For such times, you should find caster wheels that are suited to that specific task. This article highlights three situations when you should get specialised casters, and how to choose them for best results.

1. Delicate payloads

Delicate loads must have special care to ensure moves are secure and smooth. Some applications include medical loads, explosive loads and sensitive electronics. Usually, you'll find specialized casters for each of these applications, but it's important to consider such factors as the surface on which the load will be moved, size of load and usage among others.

For instance, medical carts periodically need to be cleaned in disinfecting cabinets using abrasive chemicals. Choose extras such as directional and total locking brakes, polyamide plastic housing which is easy-roll, quiet and rust-free and positive wheel lock so that locking action won't depend on friction. For electronics, you'll need conductive casters to prevent buildup of static electricity that can damage to sensitive electronics. These casters redirect static electricity to the ground (grounding).

2. High temperatures

The most important characteristic for high-temperature applications is wheel material. Most all-purpose casters are intended for temperatures no higher than 65°C. High temperature affects caster performance, durability, maintenance requirements or potential for failure. Some high-temperature applications include industrial environments like autoclaves, curing ovens, bakeries etc.

Polyurethane wheels are commonly used for low-temperature applications, and can still be used if temperatures don't exceed 82°C (180°F). Closer to this temperature, however, there's a higher risk of failure or flat-spotting. Nylon casters can be used up to ≈120°C (250°F), but some can withstand up to ≈205°C (400°F). Beyond this temperature, cast iron and steel casters are the only ones that can be used (up to 315°C or 600°F), and load capacity will be reduced as the material loses strength with prolonged high-temperature exposure.

In addition, choice of lubrication should be evaluated to avoid excessive friction and the resultant wear. Specialised grease, graphite and dry film lubricants are common choices.

3. Machine-levelling and retracting casters

Machine-levelling casters are intended for very heavy machinery that may need occasional movement. The ideal casters should have heavy-duty wheels with solid, broad polyurethane feet which can be lowered to raise the wheel from the floor when in stationary mode. It should provide for fine-tuning the elevation so that the machine is properly stabilized depending on the surface you're working on.

Retracting casters can also serve the same purpose, such as lifting a heavy workbench. Each caster is attached to the lower side corner of a bench and held using through bolts or lag screws. A foot-operated lever is used to raise and lower the wheels as needed. Wheel ratings will be according to the load to be carried.