Office Chair Replacement Rod

When the gas spring of an office chair is damaged, it can be repaired by replacing it with a gas spring of the same specification, without the need to discard the chair. The gas spring is the core component of the office chair's height adjustment function, consisting of an inner rod and an outer cylinder. Damage can result in the seat being unable to rebound or experiencing stuck height adjustments. The replacement process involves three steps: disassembly, selection, and installation, which are simple to perform and have a low cost (approximately 30 yuan or less). Details are as follows:

I. Disassembling the Old Gas Spring

1. Separating the Seat from the Gas Spring
   Lay the chair down and use your foot to hold the base steady. Grasp the seat with both hands and shake it repeatedly, using inertia to loosen and separate the seat from the top connector of the gas spring. If the connector is too tight, you can lightly tap the bottom edge of the seat with a rubber mallet to assist in separation.

2. Removing the Old Gas Spring
   Use a wrench or pipe wrench to hold the bottom of the outer cylinder of the gas spring steady, and use a hammer to tap the edge of the outer cylinder with the other hand (avoid tapping the bottom to prevent damage to the base threads). If the outer cylinder is rusted to the base, you can first spray a small amount of penetrating oil or wrap the outer cylinder with Teflon tape to increase friction before twisting. If it still cannot be removed, use locking pliers to grip the outer cylinder and rotate it to pull it out.

II. Selecting a New Gas Spring

1. Measuring Key Dimensions
   Use a tape measure to measure the total length of the original gas spring (the distance from the mounting surface of the base to the top of the seat connector), ensuring that the length of the new rod has an error of no more than ±2mm. The diameter of the gas spring connector is usually a standard specification (such as 25mm or 28mm), but you need to confirm the type of connector on the original rod (such as threaded or snap-on) to match the base.

2. Verifying Compatibility
   Prioritize selecting a gas spring of the same brand or model as the original. If this is not possible, confirm that the load-bearing capacity of the new rod (such as suitable for 50kg-120kg) matches the design load of the chair to avoid secondary damage due to insufficient load-bearing capacity.

III. Installing the New Gas Spring

1. Securing the Base
   Insert the new gas spring vertically into the mounting hole of the base, ensuring that the bottom of the outer cylinder is fully embedded in the base threads or slot. If it is a threaded connector, rotate it by hand until it cannot turn further, and then use a pipe wrench to tighten it 1-2 more turns (do not overtighten to prevent thread stripping).

2. Assembling the Seat
   Align the seat with the top connector of the gas spring and slowly press down to fully embed the connector into the seat hole. Sit on the seat and shake it slightly, using your body weight to ensure a tight fit between the connectors. If the connector is loose, you can lightly tap the bottom edge of the seat with a rubber mallet to assist in securing it.

Precautions

• Wear gloves before operating to avoid cuts from metal parts.
• If the chair has been in use for more than 5 years, it is recommended to simultaneously check whether the five-star base is deformed to prevent the new gas spring from being damaged again due to an unstable base.
• After replacement, slowly raise and lower the seat 3-5 times during the first use to ensure stable gas pressure inside the gas spring.

By following the standard procedure for replacing the gas spring, the office chair can regain its height adjustment function and extend its service life by 3-5 years. If you are unfamiliar with the disassembly steps, you can search for "office chair gas spring replacement video tutorial" for practical demonstration references.