Office Chair Scratching Floor

The issue of an office chair scratching the floor can be caused by problems with the gas lift, base, casters, or due to an uneven floor surface or overloading. Here are the specific causes and analyses:

1. Gas Lift Issues

• Damaged and Sinking Gas Lift: The gas lift is filled with nitrogen and controls the chair's height adjustment through a valve. If the seal ring ages, causing gas leakage, or if the valve gets stuck and cannot be adjusted properly, the seat height will drop abnormally, causing the edges of the base (such as plastic covers or metal brackets) to rub directly against the floor. This scraping sound is particularly noticeable when used on hard floors like tiles or wooden floors.
• Improper Adjustment of the Gas Lift: If the height adjustment is set to the maximum or minimum limit and used for a long time, the exposed part of the metal rod may become too long and directly contact the floor. For example, when the chair is adjusted to the lowest position, the base may completely touch the ground; when adjusted to the highest position, the rod may tilt and touch the ground due to a shift in the center of gravity.
• Aging Gas Lift: For chairs that have been used for more than 3 years, the aging of the seal ring reduces the stability of the gas lift, causing the rod to sink under pressure and increasing the risk of scratching the floor.

2. Base Issues

• Deformed and Unbalanced Base: Low-priced chairs often use thin steel or inferior plastic for their bases, which can easily twist and deform under long-term weight bearing, causing one side of the base to press down on the floor. People who are heavier or who habitually sit at an angle are more prone to this problem.
• Base Impact or Loose Screws: If the chair is bumped, causing the base to deform, or if the screws at the connections are loose, the gas lift may tilt, indirectly causing the base to touch the ground.

3. Caster Issues

• Detached/Stuck Casters: Loose casters can change the chair's support points, forcing the gas lift to bear more pressure and accelerate sinking. If the casters are blocked by hair or threads, preventing smooth rolling, this can also indirectly cause the base to touch the ground. A combination design of nylon casters and metal bearings can reduce this risk.
• Caster Material Issues: Hard plastic casters (such as PP/PU hard wheels) have a smooth surface but lack elasticity. When rolling on hard floors for a long time, the wheel surface may accumulate sand or dust, creating a sandpaper-like friction effect and leaving fine scratches.

4. Other Factors

• Uneven Floor: Some office floors renovated from old factory buildings may have a slight incline, causing the chair to touch the ground on one side due to a shift in the center of gravity. It is recommended to check the chair's balance every six months.
• Overloading: Professional office chairs usually have a weight limit (mostly within 120kg). Overloading can cause the structure of the gas lift to deform, directly leading to the problem of the chair scratching the floor.