Office Chair Base Replacement

Replacing the base (chassis) of an office chair should be done according to standard procedures. The specific steps are as follows:

I. Preparation

1. Tools and Materials

   • Basic tools: Phillips/flat-head screwdrivers, rubber or plastic mallet, adjustable or open-end wrench, cloth.
   • Special case handling: If the screws are rusted, prepare a loosening agent (such as WD-40) or rust remover.
   • New base selection: Measure the hole spacing (distance between screw holes, e.g., 14cm×17.5cm) and the diameter of the center hole of the old base to ensure compatibility with the new one. Prioritize selecting a reinforced steel base with a thickness of ≥3.0mm to ensure load-bearing capacity and durability.

2. Safety and Environment

   • Clear the work area, choose a flat and spacious location, and lay down soft padding to protect the floor.
   • Wear protective gloves during operation to prevent cuts; adjust the gas lift to its lowest position to reduce operational risks.

II. Removing the Old Base

1. Separating the Five-Star Base from the Wheels

   • Invert the chair onto the soft padding and pull the casters straight up. If the wheels are stuck, rotate them slightly before pulling.

2. Separating the Five-Star Base from the Gas Lift

   • Use a rubber mallet to evenly tap around the connection between the center steel ring of the five-star base and the gas lift. Try to pry the five-star base loose. Repeat the 'tap-pry' action until they separate. Avoid using a metal hammer to prevent paint damage or component indentation.

3. Removing the Seat from the Base

   • Use a screwdriver to remove the screws (usually 4) that secure the seat to the base, separating the seat from the base (including the gas lift).

4. Separating the Gas Lift from the Old Base

   • Raise the gas lift to its highest position. Use a rubber mallet to evenly tap around the steel ring connecting the chassis to the gas lift while pulling up and down with your hands or stepping on it to assist in separation. If stuck, tap multiple times or spray with a loosening agent before operating.

III. Installing the New Base

1. Assembling the Five-Star Base and Gas Lift

   • Taking the P600 office chair as an example: Place the five-star base bottom-up, insert 5 casters, then insert the thick end of the gas lift into the five-star base and press gently to ensure a secure connection.

2. Securing the Base to the Seat

   • Align the base with the screw holes on the seat cushion, secure with 4 short screws (e.g., 6×20 size), and tighten to ensure no looseness.

3. Connecting the Gas Lift to the Base

   • Insert the gas lift into the round hole of the base, adjust the armrest cushions and lumbar support to a comfortable position, and complete the installation.

IV. Precautions

• Parameter Matching: The hole spacing and center hole diameter of the new base must match those of the old one to avoid installation failure or safety hazards due to incompatibility.
• Operational Standards: Use a rubber mallet preferentially during disassembly to prevent damage to metal components; if components are rusted, spray with a loosening agent before operating.
• Safety Inspection: After installation, test the chair's lifting and rotating functions to ensure they are normal and that there are no unusual noises or looseness.