Office Chair Hydraulic Repair

The hydraulic rod of an office chair usually cannot be repaired and needs to be replaced as a whole. Users can diagnose, replace, and install it themselves. Here are the specific steps:

Fault Diagnosis

• Common Faults: Lifting malfunction, automatic sinking, inability to lock the height.
• Specific Manifestations and Causes:
  • Complete inability to lift or lower: It may be that the internal valve of the pneumatic rod is completely stuck or the seal is ineffective, or there may be insufficient hydraulic oil or internal blockage.
  • Slow automatic sinking: Slow leakage of internal gas or seal failure.
  • Lifting stuttering or abnormal noise: Wear of internal structure or ineffective lubrication, or debris or rust at the connection of the lifting rod.
  • Loose lifting rod: Try tightening the screws first.

Preparation Before Repair

• Tools: Large pipe wrench (or adjustable wrench), rubber mallet, gloves, goggles, wrench, Phillips or flat-head screwdriver, lubricating oil (sewing machine oil or WD - 40 are acceptable). If the hydraulic rod needs to be replaced, purchase a new one of the same specification in advance.
• Worksite and Safety: Operate on a flat ground. When flipping the chair, ensure that the seat surface is placed face down and stable. The pneumatic rod is filled with high-pressure nitrogen gas inside. Drilling, sawing, heating, disassembling, violent hammering, or forcibly prying the rod body are strictly prohibited to prevent gas from bursting out and causing injury.

Repair Steps

1. Safely Remove the Old Hydraulic Rod: Separate the five-star base and the seat. Use a pipe wrench to grip the metal collar and rotate it counterclockwise, or pry open the snap ring and unscrew the fixing screws.
2. Accurately Measure and Purchase a New Rod: Measure the total length, pipe diameter, and stroke. Take the old rod or a photo of its dimensions to purchase a new rod of the same size, grade, and with safety certification.
3. Install the New Hydraulic Rod: Clean the interface, rotate it clockwise to connect it to the five-star base, install the snap ring or fixing screws, and place the chair upright to test if it operates smoothly and locks firmly.

Other Precautions

• Simple Adjustment: Confirm that the adjustment direction is correct.
• Lubrication Maintenance: Clean and lubricate the connection of the lifting rod.
• Inflation Operation: If the air pressure is insufficient, you can try to replenish the gas. Note that the recommended pressure range is 0.5 - 1.0MPa, and avoid over-inflation.
• Decision-making Advice: It is worth replacing when the chair structure is intact and only the gas rod is damaged. If the five-star base is damaged or aged, it is recommended to replace it together.
• Preventive Maintenance: Avoid frequent rapid lifting and lowering, do not overload the chair, keep the rod body clean and dust-free, regularly clean the surface of the hydraulic rod, and lubricate the moving parts every six months.