Industrial foot wheel load is an important reference standard. Industrial casters should always run stably on the ground. However, it is almost a purely theoretical state. On the surface of the uneven, or when crossing the threshold, track and pits, the industrial casters will leave the ground briefly. So, when they are suddenly overloaded or when only 3 of the four industrial casters touch the ground, the caster must carry the entire load. This must be taken into account when calculating the load.