Office Chair Pillar Sinking

When the office chair pillar sinks, first identify the cause and then address it accordingly. Here are some common causes and solutions:

Aging of the Seal Ring in the Pneumatic Rod

The seal ring inside the pneumatic rod is usually made of polyurethane or high-performance rubber composites. Over long-term use, problems such as stress relaxation, oxidative degradation, and the accumulation of micro-cracks can occur, leading to a decline in sealing performance. High-pressure nitrogen escapes, accelerating the sinking speed. However, the performance degradation of the pneumatic rod often follows a 'plateau-jump' pattern, and rapid sinking is not necessarily solely due to seal ring aging. Factors such as scratches on the piston rod surface, deposits on the inner wall of the cylinder, and environmental temperature differences can also have an impact. If the seal ring is severely aged, you can try replacing it, which may restore most of the functionality. However, if the inner wall of the cylinder has mild rust due to long-term micro-leakage, or if the piston rod coating has irreversible wear, simply replacing the seal ring can only delay the degradation.

Damage to the Pneumatic Rod

Wear on the support rod can make it unable to withstand pressure when heavily loaded, causing the office chair pillar to sink. In this case, the best measure is to replace the pneumatic rod to restore the normal functionality of the office chair.

Incorrect Engagement of the Regulator

The adjusting rod may get stuck or be misaligned, and continuous pressure applied to the button can create a sinking sensation. At this time, check whether the adjusting rod is working properly. If there is a problem, adjust it to the correct state.

Temporary Repair Methods

• Using a Hose Clamp: Slide the plastic skirt down from the cylinder to expose the metal cylinder. If the plastic skirt covers the cylinder body, remove it first. Adjust the chair to a suitable height and wrap the hose clamp around the cylinder without tightening it initially. You can improve the grip of the clamp by wrapping rubber bands, tape, or sanding the cylinder. Tighten the clamp as much as possible and test the chair. If the height is incorrect, move the position of the clamp. If the clamp slips, you can fix it with a rubber strip or try other methods.
• Using PVC Pipes: Measure the diameter and length of the chair's cylinder. Purchase PVC pipes with the same or slightly larger diameter as the cylinder and an appropriate length. You can also use plastic shower rings as a substitute, but they may not be sturdy enough. Split the PVC pipe lengthwise. Wear a mask or respirator to avoid inhaling particles. If you don't have cutting tools, you can keep the pipe intact and remove the chair's wheels. Slide the pipe over the chair's cylinder and make it fit snugly around the cylinder to prevent the chair from slipping.