How to Select the Right Caster Wheels
If you want to transfer heavyweight from one place to the other, you need the right transport device. This must be equipped with suitable rollers so that the transport can be successful. However, it is not always easy to know which caster wheels are the right ones for the job, and what requirements are needed. Your selection will depend on different factors. In this article I will give you an overview of the most important criteria for the choice of wheels and rollers.
- The carrying capacity of the rollers
- The mounting of the wheels
- The tread material
- Steering or fixed casters - the types
- Mounting types of rollers
- Further criteria for the selection
Crucial for the right selection of caster wheels is the weight of the load you want to transport. Therefore, you need to know the minimum carrying capacity of a single roll. Use the following calculation: The weight of the transport device + the weight to be transported divided by 3. The reason for dividing it by 3 is, that on an uneven ground, temporarily the device may stand on just 3 rollers. In this case, the carrying capacity of 3 rollers must be sufficient.
To choose the right caster wheels for your job, you have three options. Each one comes with its specific properties. It is the characteristics of each of those castors which are making all the difference:
They are inexpensive and relatively maintenance-free. In the transport sector they are only used with polyamide wheels and special applications in the wet area, where roller bearings would be threatened by corrosion.
They are ideal for frequent use. Usually, they are maintenance-free.
They are suitable for the highest demands, even for adverse conditions and high payloads. Their advantage is in their excellent runnability.
In terms of mounting of the wheels, it is therefore essential that you know what you want to transport before you buy the caster wheels. If you use the transport device only occasionally, roller bearings are often perfect. In other cases, investing in ball bearings is worthwhile.
When choosing wheels and rollers, the tread material is often neglected. It decisively influences the properties of the caster wheels. In this context, the following characteristics play a particularly important role:
- Heat resistance
- Resistance to chemical substances, oils and fats
- Load capacity.
For the tread material, there are also different materials available. The cheapest choice is usually polypropylene. Among the advantages of this material is its high chemical resistance. However, polypropylene wheels have only a medium service life. The load capacity is limited, and they are hardly suitable for transport on uneven floors. Also, they are not ideal for cold storage houses. In this case you would be better off with polyamide wheels.
Solid rubber is very common as tread material. Wheels made of this material perform well on uneven ground but often flatten over more extended periods of use, so that a rough run can be the result.
An even higher quality material is thermoplastic rubber and solid rubber elastic. If you want to transport heavy loads in particularly adverse conditions, invest in wheels or rollers with a polyurethane tread material. This is extremely robust and durable. It also scores with excellent running properties, is highly chemical resistant and has a high weight capacity.
Swivel or fixed casters
Depending on the job at hand, you have two different choices
- Swivel or
- Fixed casters.
Swivel casters can be swiveled for smooth steering. However, they also can be equipped with a detent. If detent only blocks the pivoting movement and not the wheel position, it is called a directional lock. Typically, total locks are used, which prevent both the rolling and the pivoting of the casters. The actuation takes place by locking each individual caster. High-quality transport utensils are often equipped with a central brake, which blocks both wheels with just a one-foot pedal.
Fixed casters, they are rigid and can not be swiveled.
Most transport equipment has two swiveled and two fixed casters. Classically, the two swiveled casters are on the front of the unit and the two fixed castors at the back. However, the reverse can also be the case. Ergo pressure devices, for example, have two swiveled casters at the back and two fixed castors at the front.
Trolleys with four swivel casters can be rotated on the spot, much like a shopping trolley. They are very flexible. As a result, this arrangement is particularly well suited for narrow aisles. Running them in a straight line, is less satisfactory. If two swivel casters are equipped with directional detectors, they can be locked in place for longer straight-ahead rides, making them almost fixed casters.
Both the swiveled, and the fixed caster wheels, must be attached to the relevant transport equipment to perform their task correctly. There are different types of how casters can be mounted. In the commercial sector mounting plates are widely used. These are usually standardized and available in various designs. They are easy to mount; often, all you need is a screwdriver to fasten the casters through a hole in the steering device.
Further selection criteria
Another factor is the wheel diameter. It determines the rolling and starting resistance in conjunction with the ground condition. Also, judge the hardness of soils. Hard wheels are recommended for soft flooring and vice versa. In an electrostatic protected area, you should use only electrically conductive rollers.
Conclusion — what caster wheels you chose depends on many factors.
Before selecting, consider what tasks wheels and rollers should perform:
- How heavy are the loads you want to transport?
- On what flooring do you want to transport it?
- What are the temperatures during transport?
- Do the casters come in contact with chemicals?
- Do you maneuver in narrow corridors?
Lastly, the price also plays a role. Saving on good casters is not recommended. After all, the nature of the caster wheels will affect your daily work.