When selecting a wheel or a castor as to their load capacity, the following factors have to be taken into account:
Layout of wheels or castors in the vehicle (choose K number according to the drawing).
Load capacity of a wheel or castor is calculated according to the following formula:
Load capacity of a wheel or castor = (weight of the vehicle + weight of the load carried)/K

Values in the table of the load capacity are given, retaining the following conditions:

• speed: 4km/h
• roughness height: 5% of the wheel diameter for rubber or pneumatic tire and 2,5% of the wheel diameter for solid wheels and wheels with polyurethane tire
• temperature 20°C

Wheels are tested on a regular basis in accordance with the standards EN 12527, EN 12528, EN 12531, EN 12532, EN 840-5.
When loading the vehicle cyclically, the wheels must not be loaded up to their nominal load capacity.