How to Overlap Office Chairs

Office chairs should be overlapped following the principles of 'tight fit, low center of gravity, and same type', achieving safe stacking through reasonable handling of the base, layer-by-layer fitting, weight distribution, and height control.

1. Handle the base to ensure a secure fit
   Insert the chair legs into the gaps of the lower chair's legs, ensuring that each layer of legs is nested together to avoid misalignment and uneven force distribution. For example, with four-legged office chairs, the upper chair legs should be precisely inserted into the gaps of the lower chair legs to form a 'locking' structure, preventing lateral sliding. If the chair has wheels, the wheels should be placed downward against the ground, and the wheels should be turned inward or removed and stored separately in advance to avoid scratching the seat surface or causing instability due to wheel movement.

2. Fit layer by layer to fix the contact points
   The structure of the upper chair should fit correspondingly with the lower one to form a fixed support. For example, the backrest can be inserted into the groove of the lower backrest, and the armrests should be aligned with the lower armrests to ensure that each layer has a clear contact point, preventing left-to-right wobbling. This step reduces the lateral width, improves space utilization, and avoids center-of-gravity shift due to structural misalignment.

3. Distribute weight reasonably to lower the center of gravity
   Place chairs with wheels or heavier chairs on the bottom layer and lightweight chairs on the upper layers. Having the wheels downward increases friction with the ground, preventing sliding; placing heavy objects at the bottom lowers the overall center of gravity, enhancing stability. Avoid a 'top-heavy' stacking method, such as not placing a metal-frame chair on top of a plastic chair, as a slight collision could cause it to topple.

4. Control the stacking height to prevent risks
   It is recommended to keep the regular stacking height at 5-6 layers, with a maximum of no more than 10 layers. Too many layers will cause the center of gravity to rise, and in areas with air vents or high foot traffic, slight shaking may trigger a chain reaction of toppling. If stacking to the maximum height is necessary, choose a flat ground, keep away from walkways, and secure it with flexible straps to prevent scattering due to external collisions.

5. Use auxiliary techniques to enhance safety
   Before stacking, clean the chair legs and contact surfaces to avoid dust or debris affecting the fit. When moving the stacked chairs, wrap them 2-3 times in the middle with flexible straps (such as cloth or rubber bands) to increase overall rigidity. For long-term stacking, place soft pads (such as foam boards) between the seat surfaces to prevent indentation or deformation due to pressure.