Wheels
The 10 most important properties of casters
Our casters are designed and manufactured for years of use. Each caster, from office chair casters and furniture casters to appliance casters and industrial casters, has unique properties that optimize rolling comfort and rolling enjoyment. On this page you will find 10 important properties of transport wheels, swivel casters and rigid casters:
- Lifespan
- Object
- Intensity of use
- Environment
- Temperature
- Humidity
- Static electricity
- Chemicals, oil products, water and steam
- Surface
- Load-bearing capacity
1. Lifespan
Our high quality casters are made to have a long lifespan. However, this depends on a number of factors such as the environment, the substrate, the right material and an appropriate load.
2. Object
Office chairs, sitting chairs, furniture, beds, tool carts, interior cabinets, industrial cabinets, trolleys, pallet trucks and scaffolding are just a few examples of objects that can be equipped with casters and wheels.
For almost every object there is a fitting caster. You will find the perfect caster for your application by choosing a caster that fits the environment and the surface in which it must function.
Appropriate load capacity and the right material of both the wheel and optional brackets are also important for a proper operation of the castors.
3. Intensity of use
Castors can be suitable for non-intensive, for normal and for intensive use. Castors for non-intensive duty are mainly intended for static load and to move the object only occasionally. These types of casters are often used for light furniture, displays and other light structures.
However, most series of casters, whether furniture casters, appliance casters or industrial casters, are for normal to intensive use. They can be both statically loaded and can be used daily for moving the object.
4. Environment
The environment in which casters and wheels operate consists of four factors. The temperature of the environment, the humidity of the environment, possible static electricity in the environment and the possible presence of chemicals, oil products, water and steam in the environment.
5. Temperature
Depending on the type of transport wheels, swivel castors and rigid castors it is or is not suitable within a certain temperature range. When a caster is suitable for operating in lower or higher temperatures, the load capacity of the caster may be reduced.
When using castors at high or low temperatures, stainless steel housings are recommended. A special lubricant may also be required.
Overall, almost all casters maintain their load capacity at a temperature range of 0o degrees Celsius to 40o degrees Celsius. Depending on a lower or higher temperature and the type of tread, the load capacity can decrease considerably:
Castors with solid rubber tread
These castors maintain 80% of their load capacity at a temperature of 0o to -20o Celsius. The load capacity decreases sharply at even lower temperatures and may drop to 40% of the load capacity at temperatures down to -40o Celsius.
Castors with elastic rubber tread
These casters generally maintain their load capacity well, even at somewhat lower or higher temperatures. At temperatures lower than -20o Celsius the load capacity does decrease quickly to 40% at a temperature of -40o Celsius. At temperatures higher than 40o Celsius the load capacity decreases slowly to 45% at temperatures between 80o and 120o Celsius.
Castors with polyurethane tread
These casters are not suitable for temperatures below -20o Celsius and until that temperature retain 100% of their load capacity. At temperatures above 40o Celsius the load capacity slowly decreases. At 80o Celsius it still has a load capacity of 80%. At even higher ambient temperatures the load capacity decreases rapidly to 40% at temperatures up to 120o Celsius.
Castors with an injected polyurethane tread
Castors with this tread type are not suitable for temperatures below -20o Celsius and retain 100% of their load capacity up to that temperature. At an ambient temperature higher than 40o Celsius the load capacity decreases to 40% at a temperature range of 80o Celsius to 120o Celsius.
Castors with polyamide tread
These castors retain 100% of their load capacity at a temperature range of -20o Celsius to 40o Celsius. However, at lower temperatures down to -40o Celsius the load capacity rapidly decreases to 50%. At higher temperatures the load capacity decreases slowly and maintains 60% of the load capacity at a temperature of up to 120o Celsius.
Castors with synthetic resin tread
These casters are well suited for high temperatures. They retain 100% of their load capacity at a temperature range of -20o Celsius to 120o Celsius. The load capacity of the wheels with a synthetic resin tread does decrease rapidly at lower temperatures. At a temperature of -40o Celsius it has 40% of its total load bearing capacity.
Castors with a cast iron tread
These casters have an excellent load capacity over a wide temperature range. They retain 100% of their load capacity at a temperature of -40o Celsius up to and including 120o Celsius.
Castors with pneumatic tires
These casters have an excellent load capacity as long as it is used within the specified temperature range. Pneumatic tires retain 100% of their load capacity at a temperature of -20o Celsius up to and including 60o Celsius.
6. Humidity
Almost all casters, furniture wheels and other transport casters are suitable for use in non-permanent moisture conditions. A little rain, occasional condensation or driving over a damp or wet surface is therefore not a problem, as long as the castors can dry out afterwards.
When casters are used in a permanently wet environment, it is important to select casters that are suitable for this purpose. The core of castors, if applicable the tread, the adhesion of the tread to the core and the bearing of the castor must be resistant to humid conditions.
Castors with a vulcanized elastic rubber surface, cast polyurethane tread and polyamide wheels are suitable for use in permanently wet conditions.
7. Static electricity.
In some circumstances it may be necessary to use antistatic wheels, also called electrically conductive casters. This can occur in applications of the transport wheels in among others the chemical and pharmaceutical industry, in hospitals and when working with certain electrical equipment. Contact us when you need casters that must function in these conditions.
8. Chemicals, oil products, water and steam
When you are looking for casters that must function well in conditions with chemicals, oil products, water or steam, it is important to choose transport casters that are suitable for use in those specific conditions. Similarly, when using casters for applications in the cleaning industry with cleaning agents, it is important to choose casters that are specifically suited for this purpose. Depending on the type of wheel, tread, core and bearing, a caster may be more or less suitable, but in general the following guidelines apply:
Castors with rubber tread
In general, casters with a rubber tread are moderately suitable for use in environments with weak acids such as: fatty acids, acetic acid (30%), boric acid (10%), oleic acid, oxalic acid (10%) and sulfuric acid. The use of these appliance casters and industrial wheels is not recommended in stronger acids and other chemicals.
Castors with Polyurethane tread
Cast polyurethane wheels are generally well suited for use in environments with weak acids such as: fatty acids, acetic acid (30%), boric acid (10%), oleic acid, oxalic acid (10%) and sulfuric acid. These transport wheels are also well suited for environments where alcohol is used. The use of castor wheels with a molded polyurethane tread is not recommended in stronger acids and other chemicals.
Castors with a molded polyurethane tread
Wheels with a molded polyurethane tread are generally well suited for use in environments with weak acids such as: fatty acids, acetic acid (30%), boric acid (10%), oleic acid, oxalic acid (10%) and sulfuric acid. Also, these transport wheels are great for environments where alcohol is used. Swivel and fixed castors with a molded polyurethane tread are also excellent for exceptional conditions with water such as: salt water, cold water and water of 80o degrees Celsius. The casters can also be used in areas with saturated steam.
Castors with a vulcanized tread
Wheels with a vulkollan tread are perfectly suited for use in environments containing hydrocarbons such as: petrol, diesel, mineral oils and greases. These transport wheels are also well suited for use in environments with weak acids and alcohol. Wheels with a vulkollan tread have a moderate and limited suitability for environments containing weak bases such as: aluminum acetate, ammonium carbonate, ammonium sulfate, sodium cyanide (10%) and alkaline solutions. However, these casters are not suitable in permanently damp and wet environments.
Castors Made of Polyamide
Castors with a polyamide core are generally widely applicable in a wide range of environments. They are well to excellently suited in dry as well as moist and wet environments. These may also be environments where abnormal water conditions are present such as: salt water, cold water and water of 80o degrees Celsius. Furthermore, polyamide transport wheels are well suited for environments where weak and strong bases or solutions are used. These casters have moderate and limited suitability in environments where alcohol or saturated steam is used.
Phenolic resin castors
Castors made of phenolic resin have a wide range of applications and are excellent for use in non permanent and permanent wet environments. These can also be environments where different conditions of water are present such as: salt water, cold water, water of 80o degrees Celsius and saturated steam. Also, transport wheels made of phenolic resin are perfectly suitable to be used in environments with weak alkalis and alcohol. The casters can also be used when solvents such as: acetone, turpentine and dimethyl ether are present. Casters made of phenolic resin have moderate to limited suitability in environments where strong bases are used such as: ammonium hydrate and sodium hydroxide.
9. Surface
Casters are generally suited to specific surfaces and floors in order for the transport wheels to do their job properly and for them to be comfortable to use. The nature and condition of the surface on which casters are used is therefore important for the life of the casters.
In general, casters, such as furniture casters, with a black rubber tread may leave marks on the surface. If this is not desired then it is better to use casters with a gray or blue rubber tread.
When the applications of the transport wheels, such as furniture wheels or wheels for racks, are mainly static loads, a relatively soft tread may flatten. This is possible, for example, with casters with a rubber tread. When the wheels are mainly statically loaded, it is advisable to choose casters or wheels with a harder surface such as polyamide or polyurethane.
It can also happen, especially with device casters and industrial wheels, that the surface can cause a lot of vibration or shock loads. In such cases it is better to select wheels which are somewhat heavier and to select castors which are heavier than the load capacity would require.
In general the following guidelines apply for the type of castor according to the use on the floor concerned:
Tile floors
Furniture casters and office chair casters are commonly used for use on tile floors. In general, casters with a polyurethane or rubber tread are best suited for use on tile floors. Wheels made of phenolic resin and pneumatic tires are also excellent for use on tile floors although this application is not so common in practice.
Asphalt
For use on asphalt, often also outdoors, casters with an elastic rubber tread or pneumatic tires are generally well suited. Both types of casters are also suitable for use in non-permanent damp or wet environments. However, it is important that the casters are given the opportunity to dry out again.
Flat surfaces of concrete, cement and coating
Almost all castors are perfectly suitable for use on flat surfaces, e.g. transporters with rubber treads, apparatus and industrial castors with painted or moulded polyurethane treads, wheels with a vulkollan tread, wheels with a polyamide core, wheels with a phenolic resin tread and of course pneumatic tires. Somewhat moderate and limited suitability on flat surfaces of concrete, cement and coating are cast iron wheels.
Unpaved surface, damaged or non-planar surface.
For use on this type of surface, such as clinkers, mainly casters with an elastic rubber tread or pneumatic tire wheels are suitable. Other transport wheels are only moderately and limitedly suitable. Casters equipment with a sprayed polyurethane surface are generally not suitable at all for unpaved surfaces.
Grid floors
For the use of casters in environments with slatted floors, mainly casters with an elastic rubber tread or pneumatic tire wheels are suitable. Other transport castors are only moderately suitable or not suitable at all for use on slatted floors.
Surfaces with splinters, chips and the like
This is a difficult surface for transport wheels. For a surface with splinters and chips, really only casters with an elastic rubber tread are good to use. The use of other transport wheels is only limited or not at all suitable on this type of surface.
10. Load capacity
The load capacity required for casters depends on the type of load, the weight and the speed used for the transport wheels for internal transport.
The load capacity is also important for furniture casters and office chair casters. For these types of wheels, however, speed is of less importance given that it often has primarily a static load and the primary use is not movement.
For device casters and industrial casters, all factors are important for load capacity once they are primarily used for a dynamic load.
Smooth surface
Generally speaking, on level ground, the load capacity can be easily calculated by adding the weight of the cart and the load. The sum can then be divided by the number of wheels. The result is the load capacity required per wheel.
Uneven ground
When driving on uneven ground or over obstacles, thresholds and other uneven surfaces, it may happen that not all wheels touch the ground. When using solids as load, the sum of the weight of the vehicle and the expected load is divided by 1 wheel less than actually used. This increases the required load capacity per wheel.
For a load of liquid substances on a very uneven surface, the sum of the weight of the wagon and the expected load is divided by half the number of wheels used. This ensures that the wheels always have sufficient load capacity to carry the maximum expected load at all times.
Speed
The load capacity indicated in the characteristics of the casters and wheels applies to a speed of up to 5 km/h. At higher speeds the load capacity decreases. At higher speeds the load capacity decreases to a greater or lesser extent.
Furniture and other transport castors with solid rubber tread retain up to 50% of their load capacity at a speed of 4 - 6 km/h. Casters with a sprayed polyurethane surface and wheels made of synthetic resin also lose half of their load capacity at this higher speed. Castors with a polyamide core and tread retain 40% of their load capacity at a speed of 4 - 6 km/h.
Device casters, industrial wheels and other wheels with an elastic rubber surface, a vulkollan surface, a molded polyurethane surface, cast iron wheels and pneumatic tire wheels retain up to 80% of their load capacity at a speed of 4 - 6 km/hr.
Many transport wheels for internal transport are also not usable at speeds higher than 6km/h. Casters and wheels with an elastic rubber surface, wheels made of vulkollan and wheels with a cast polyurethane surface are suitable for speeds higher than 6km/h. They retain up to about 60% - 65% of the load capacity at a speed of 6 - 10km/h and up to about 40% - 50% of the load capacity at a speed of 10 - 16km/h.
When wheels are used at a speed higher than 4km/h it is recommended to use wheels with ball bearings.