American-style Office Chair Repair

American-style office chair repair requires handling based on the specific type of fault. Common problems and solutions are as follows:

I. Backrest Cannot Stand Upright or Adjust (Hydraulic System Failure)

If the backrest cannot stand upright or adjust, it is usually due to hydraulic rod failure. The hydraulic rod is a one-time sealed component and cannot be repaired; it needs to be replaced entirely.

1. Remove the Old Rod: Invert the chair, use a pipe wrench to grip the metal collar connecting the hydraulic rod to the five-star base, and rotate it counterclockwise to remove it. If the seat is connected with a snap ring, use a screwdriver to pry open the snap ring and remove the hydraulic rod.
2. Measure and Purchase: Measure the total length, pipe diameter (such as Class 3 or Class 4), and stroke of the old rod. Bring the old rod or a photo of its dimensions to purchase a new rod of the same specifications (price range: approximately 30-100 yuan).
3. Install the New Rod: After cleaning the interface, screw the bottom of the new rod clockwise into the five-star base, insert the top into the seat chassis, and secure it with a snap ring or screw. Test for smooth lifting and lowering.
   Note: The hydraulic rod contains high-pressure nitrogen gas. Do not drill, saw, heat, or disassemble it, as it may explode. Wear safety goggles and gloves when replacing it.

II. Chair Leans to One Side (Wheel or Seat Plate Issues)

1. Check the Wheels: Place the chair upright and upside down to confirm that each wheel foot is in contact with the ground and check for bent or damaged wheel feet. If the wheels are damaged, purchase a complete set of matching wheels (individual replacement is difficult) and tap the new wheels into the chair sockets with a rubber mallet.
2. Check the Seat Plate: If the wheels are normal, place the chair on its side and check if the metal seat plate is deformed or damaged. If the seat plate is deformed, replace or straighten the metal seat plate.

III. Other Common Problems

• Loose Screws or Transmission Component Failures: If the fixed screw for the hydraulic rod pivot point (such as a 10*1 non-standard screw) is damaged, it can be replaced with a standard No. 10 screw, and a washer can be added to prevent interference with the hydraulic rod's movement.
• Lifting Stuttering or Strange Noises: This may be due to internal structural wear or lubrication failure, requiring replacement of the hydraulic rod.

Tip: If the chair's structure is intact and only the hydraulic rod is damaged, the replacement cost is much lower than buying a new chair. Before repairing, confirm the type of fault to avoid blind operations that may cause secondary damage.