Offset (F)
Casters can be divided into non-swivelling rigid casters, which give the caster directional stability, and vertically rotating swivel casters that enable maneuvering. Maneuverability is achieved by connecting a directional lock fork to the fitting element of the wheel by means of a swivel bearing. There is a horizontal distance between the wheel axle and the swivel bearing – this distance is called the offset (F).
The offset influences the swivel resistance
When moving a transport device, the rolling and swivel resistance must be overcome. This resistance is influenced by various factors. The tread, the shore hardness of the tread and the type of floor, as well as the offset. Therefore the appropriate offset must be taken into account when selecting a caster. This allows the casters to swivel without using any aids. When moving in a straight line, the offset ensures stable running characteristics. Additionally it influences the load-bearing capacity of the casters and the amount of wear on the back bearing.
Rule of thumb for the offset
Generally speaking, swivel casters with a large offset have a lower load-bearing capacity and more wear on the swivel ball bearing, but they ensure smooth rolling characteristics. With a smaller offset the load-bearing capacity is higher and there is less wear on the swivel ball bearing, however the rolling performance is not as smooth. The optimum offset of the caster housing must be selected according to the respective requirements.
We will be happy to advise you on the matter and help you to find the casters with the optimum offset for your transport equipment. Get in touch with our experienced team!