How to caculate load capacities of our VERRO casters?

In order to determine the required load capacity of a wheel or caster,the dead weight of the transport unit,the maximum additional load and the number of wheels and casters to be used must be known. By using four or more wheels or casters,the load bearing of the individual wheels or casters can vary.
The required load capacity can be defined as follows:

                       T=(E+Z)/n*S
T=Required load capacity of the wheel or caster
E=dead weight of the transport unit
Z=Maximum additional load
n=Number of wheels or casters used
S=Safety factor

The safety factor S reflects the deviation from the standard application conditions(even floor,walking speed,load must act equally on all wheels or casters,straight travelling,ambient temperature between+15ºC and +28ºC). The safety factor is influnced by the speed and the ratio between wheel diameter and height of the obstacles. A distinction is drawn between four categories:
1)Indoor manual transport(height of the obstacles≤5% of the wheel diameter):
Safety factor:1.0~1.5
2)Outdoor manual transport(height of the obstacles≥5% of the wheel diameter):
Safety factor:1.5~2.2
3)Indoor power driven transport(height of the obstacles≤5% of the wheel diameter):
Safety factor:1.4~2.0
Ourdoor power driven transport:
Safety factor:2.0~3.0

Safety factors don't consider abrasion of the tread.

Speeds higher than 4km/h with a reduced load capacity are possible for wheels and casters with ball bearing fitted.

If a wheel or a fixed caster is mainly exposed to static loads,a load capacity is increased up to 25% can be assumed.With long endurance times under high loads,teh danger of the tread flattening must be considered.

The load capacity is stated in kg.To convert it into N,the common factors need to be implied.