When designing an industrial caster for applications with higher temperatures, many different aspects of the caster must be taken into account. Applications involving increased temperatures can have many effects on an industrial caster’s performance, such as reduced operating life, increased maintenance, or premature failure. Different examples of industrial caster applications involving higher temperature include the use in autoclaves, bakeries, curing ovens, etc. This article will discuss the tips for choosing casters and wheels that are used in manufacturing settings at elevated temperatures.
For applications below 180° F, caster wheels with polyurethane tires can still be considered but depending on the application load and speed, there is an increased risk of tire flat spotting and premature failure. When using polyurethane tires at temperature nearing 180° F the application must be properly evaluated.
Most nylon wheels can withstand up to 250° F, with some types being able to withstand intermittent temperatures up to 400° F. Nylon wheels are usually considered when ergonomics is a concern because the wheels roll with minimal force applied.
For applications in temperatures up to 600° F, wheels should be made out of either cast iron or steel. These materials also improve ergonomics and have high load capacities, but they can increase wear on the floor surface. As temperatures begin to rise past 600° F, the load rating of the caster will be reduced as the steel/cast iron loses strength. The following link shows a graph of how the strength of certain metals changes as temperature increases:
For applications at elevated temperatures; the type of lubrication used must also be evaluated. If the caster application temperatures exceed the lubrication’s rating then the effectiveness of the lubrication will be compromised. This can lead to increased friction in the wheel bearings as well as the swivel section bearings. This increased friction increases wear and reduces the life of the bearing components, which reduces the life of the industrial caster.
When designing the caster for the application, the proper lubrication can be selected for the temperature ranges. These lubricants range from specialized greases to dry film and graphite lubricants.
The bearings in the wheels and swivel section are also important aspects to consider when designing an industrial caster for a high temperature application. Besides changing out the lubricant, different bearing materials, such as ceramics, can be used. For example, most standard ball bearings are rated for applications below 300° F, while a bronze sleeve bearing can operate in temperatures ranging from 600° – 700° F but decreases roll-ability of the caster.
While wheel material, lubrication, and bearings may be large factors in determining the success of an industrial caster in elevated temperature applications, other factors must be considered as well such as the material the caster is manufactured out of. If these factors are taken into account when designing a caster for high temperature applications, the probability for success is greatly increased.