Does the load on the casters affect damage to wooden floors?

The load on casters significantly affects the extent of damage to wooden floors. The core principle is "load determines pressure"-the greater the load, the greater the pressure per unit area exerted by the caster on the floor, making it more likely to break through the floor's protective layer or damage the wood structure. The specific impact can be explained in three ways:

1. Load directly determines the "indentation risk." Excessive load can easily lead to irreversible dents.
The wood fibers and surface coating of wooden floors (especially solid and multi-layered solid wood floors) have a certain "compression limit."
When the load is within the "compatibility range" of the caster and floor (for example, a caster marked with a 15kg load capacity actually carries 10kg), the pressure is evenly distributed across the contact surface between the caster and floor. The floor's surface coating and wood fibers remain stable, leaving virtually no indentations.

If the load exceeds the caster's rated load or the floor's compressive limit (for example, a 15kg caster carrying 25kg), the pressure on the floor from the caster increases dramatically, potentially "indenting" the floor's surface coating or even squeezing and deforming the wood fibers. This type of dent caused by excessive weight is generally irreversible, especially on solid wood floors. Once the wood fibers are crushed, cleaning or maintenance cannot restore them to their original flatness.

For example, if a desk on casters is continuously stacked with books that exceed the caster's capacity (e.g., the casters are rated for 15 kg, but 20 kg of books are actually stacked), a noticeable circular indentation may appear on the floor corresponding to the caster after 3-6 months. This indentation will gradually deepen with use.

2. Load exacerbates "friction damage." Overloaded casters can easily cause jamming and scratching of floors.
The smooth rolling of casters depends on the "wheel body's rotational resistance" and "load matching":
Under normal load, the caster body (such as PU or rubber wheels) rotates flexibly, and its contact with the floor is "rolling friction," with a low coefficient of friction, resulting in only slight, negligible surface contact.

When the load is excessive, the wheel bearings may jam due to overload (especially in low-quality casters with insufficient bearing capacity). The original "rolling friction" turns into "sliding friction"-the caster no longer rolls smoothly, but instead drags the furniture along. At this point, the caster edge or wheel surface can easily rub against the floor, directly scratching the floor coating or even scraping off the wood surface. For example, if the casters on an office chair (rated at 15kg) exceed the caster's load capacity (for example, if the user weighs 70kg, which is far more than 15kg), the caster bearings can easily become stuck, making it noticeably harder to push the chair. This can also leave distinct "strip-like scratches" on the floor. This is friction damage caused by the excess weight.

3. Load amplifies the impact of "caster defects," turning minor problems into major damage due to excessive weight.
If a caster has minor defects (such as slight wheel deformation or fine sand particles on the surface), they may not significantly affect the floor under normal load. However, excessive weight can magnify the damage caused by these minor defects.

For example, if a caster has a 1mm diameter grain of sand on its surface, under a normal load (10kg), the pressure between the sand and the floor is minimal, likely leaving only a very shallow mark. However, under an excessive weight (20kg), the sand will be "pressed" into the floor surface, creating "long, narrow scratches" as the caster moves. These scratches penetrate the floor coating and damage the wood itself.

For another example, if a wheel has minor deformation (such as a bulge on a PU wheel), under normal load, the deformation has a small contact area with the floor, resulting in minimal impact. However, under excessive weight, the deformation becomes a "stress point," generating localized high pressure on the floor. This not only easily leaves an indentation, but can also cause "jumping friction" due to uneven wheel rotation, scratching the floor.

Summary: The "positive correlation" between load and floor damage.
Simply put: the greater the load, the higher the risk and severity of damage to wooden floors. Therefore, in actual use, it's important to strictly adhere to the principle of "rated load capacity ≥ actual load capacity" (it's recommended to allow a 20%-30% load margin; for example, a 15kg load-bearing caster should not exceed an actual load of 12kg). Also, choose casters that match the flooring material (for example, wide-body casters are preferred for solid wood floors to distribute pressure by increasing the contact area). This helps minimize damage to the floor from the source.