Office Chair Cylinder Replacement

Replacing the cylinder of an office chair can be done following these steps. Operate carefully and in accordance with regulations to ensure safety and effectiveness:

Step 1: Prepare Tools and a Compatible Cylinder You need to purchase a cylinder of the appropriate model in advance. A common specification is a 4-stage cylinder (which can be bought on platforms like Taobao). Make sure its size matches the original cylinder. Also, prepare tools such as a pipe wrench (for gripping the cylinder), a hammer (for assisting with disassembly), and a screwdriver (for removing the base's fixing clips). If the cylinder has an anti-rust coating on its surface, you can prepare a small amount of lubricating oil to assist with disassembly.

Step 2: Disassemble the Old Cylinder

1. Separate the Wheels from the Base: Turn the office chair upside down so that the five-claw base faces upward. Install the wheels one by one back into the wheel holes of the five-claw base (if the wheels have already fallen off, skip this step). Use a screwdriver to push and press the fixing clips on the edge of the base (usually plastic snap-fit structures) and pull out the wheels outward at the same time.
2. Remove the Old Cylinder: Use a pipe wrench to fix the middle part of the cylinder (avoid damaging the cylinder surface). Hold the base with the other hand and pull it upward. If the cylinder is too tightly connected to the base, you can lightly tap the top edge of the cylinder with a hammer to loosen it using the vibration and then remove it. Note: Keep the cylinder vertical during disassembly to prevent sudden release of internal air pressure, which could cause parts to fly out.

Step 3: Install the New Cylinder Insert the large end (the end with a larger diameter) of the new cylinder vertically into the center hole of the base. Make sure the cylinder is fully flush with the base and not tilted. Lightly press the top of the cylinder to check if it is firmly embedded in the base. If the cylinder has an adjustment knob, confirm that the knob faces a direction that is easy to operate (usually the outer side).

Step 4: Assemble the Seat Cushion and the Base

1. Fix the Seat Cushion Tray: Turn the handle of the tray at the bottom of the seat cushion to the side (to avoid it digging into your legs during subsequent use). Align the hole positions of the tray with the threaded holes at the top of the cylinder.
2. Install the Screws: Pass through the gasket (if included in the accessories) and the hole positions of the tray one by one. Use a screwdriver to tighten the screws until they cannot wobble. Key Point: Tighten the screws multiple times in a diagonal order to prevent the tray from being deformed due to uneven force.
3. Connect the Seat Cushion and the Base: Align the assembled seat cushion part with the top of the cylinder on the base. Slowly press down so that the cylinder is inserted into the center hole of the tray. When you hear a 'click' sound, it means the installation is in place.

Alternative Solution: If the cylinder is not severely damaged (such as only slightly sinking), you can try using a hose clamp (tightly clamping it around the middle of the cylinder to limit its expansion and contraction) or a PVC pipe (cut into a sleeve of the same length as the sunken part of the cylinder and put it over the cylinder to fix the height) for temporary repair. However, these methods may affect the chair's adjustment function, and it is recommended to replace the cylinder as a priority.