Hi, my name is Jesse. I recently moved to the country, and with the extra space on my new property, I have bought a lot of new "toys". Now, I have everything, from a ute, to recreational vehicles, to all-terrain vehicles, to a small jeep. Each of them, I have learned, need different qualities from their tires and wheels. I love thinking about tires and wheels, repairing them, buying them and maintaining them, but I also know the issue isn't always as simple as it seems. If you have questions or just want to learn something new about tires, I invite you to explore my blog. Thanks for reading.
Selecting the right caster wheel for any application is about considering the environment and purpose for which you need to have it. By taking time to understand the application and how caster wheels factor into it, you can ensure that your wheels make your life easier, not harder. These are some of the important points to remember in the planning process.
1. Load capacity
The first step is to know the weight that the caster will support. Consider the cart/machine's weight at its heaviest, and then add an allowance of about 25-30 percent for added safety. To determine caster loading, you should consider floor conditions as well. The load rating is an expression of the weight each wheel can bear as a percentage of the total weight of cart/machine when fully loaded, and is different for normal and extreme floor conditions.
To find it easily, divide the total loaded weight of cart/machine (plus allowance) by 3 wheels – three and not four because floors aren't perfectly flat, and frequently only three of the four casters may have to bear most of the weight. The load rating calculated this way doesn't provide for shock loading i.e. dropping large weights onto the machine instantly. If shock loading will often occur, the weight allowance above should be raised by 250-300 percent.
2. Floor conditions
Casters ideally work best when operated on flat, cement floors, but this isn't always possible, especially in industrial settings: you may have old floors with wetness, potholes, spillages, debris and more, all of which reduce the efficiency of casters. Choose softer resilient casters over hard-tread wheels for floors with shallow potholes; they roll easier. You should also increase the load capacity when you have floor defects. If there are metal shavings or other debris that may puncture the surface of the caster, steer clear of softer materials like rubber in favour of hard-tread materials.
The temperature of the space is important if the casters won't be operated within the normal temperature limits. Exposure to moisture also affects your choice of material as well as the ideal finish for efficiency and longevity.
Regarding material choice, polyurethane tyres can be used for applications below 68°C (180F), but care should be taken when approaching the limit, since the risk of premature failure and flat-spotting increases. Nylon tyres are stable up to 120°C (250F), though some can withstand exposure to sporadic high-temperature spells up to 200°C (400F). Use steel or cast iron wheels for applications exceeding 200°C as far as 315°C (600F). Of course, proper protection against rust should be considered, especially in moist environments.
The temperature will also affect the method of lubrication, since efficacy of the lubricant will be affected if temperatures are higher than the recommended limits. As a result, you'll have damage from increased friction, reducing the lifespan of your caster wheels.