Lexicon: T
The housing of a caster
A caster basically consists of three important components: the wheel, the fitting and the caster housing. When considering housings, a distinction is made between housings for rigid casters and housings for swivel casters. Swivel caster housings can rotate around a vertical axis and threfore allow the caster to move in any direction. In contrast, rigid caster housings are fixed and allow only one direction of travel.
Caster housing are usually made of sheet steel in different weights or malleable cast iron. In some cases, plastic housings are used. The advantage of this variation is that it is very insensitive to chemical influences and weather conditions, but its load-bearing capacity is limited compared to other materials.
The housing construction is designed to achieve the highest possible load-bearing capacity and easy swivelling with a low construction height. The offset is an important factor, for example, the distance between the center of the wheel axle and the center of the king pin. The offset influences the swivel capacity, the load capacity, the wear of the back bearing and the operating behavior of the caster.
Back bearing or swivel bearing
The type of swivel or back bearing needed depends on the load and the running properties of a caster. Plain bearings are commonly used for lighter loads – such as for furniture or chair casters. For higher loads, ball bearings are used. These are available in versions with a single or double ball race, as a deep groove ball bearing. The latter rotate easily even at maximum load and are wear-resistant. For particularly heavy loads, again roller bearings are to be preferred. Because of their large diameter, they take up a high load torque;
Housing surface finish
To ensure the housing is durable, a surface finish is recommended. The choice of finish depends on the environment in which the casters are to be used. Stainless steel or washable casters are ideal for stringent hygiene requirements. Similarly, a sealed swivel back bearing helps prevent corrosion of the bearing.
Do you have any questions about the housing or surface protection? Please contact us – we will be happy to help you!