Welding Office Chair

Welding office chairs generally use arc welding, a common method that melts and connects the base material through the heat of an electric arc. It is suitable for metals such as iron, steel, and stainless steel, and requires attention to operational specifications and process control.

I. Key Points of Basic Welding Operations

1. Limitations of Single-Person Operation
   When welding the bottom bars of an office chair, the support bars need to be spread out to both sides to facilitate welding. This process usually requires two people to work together, as it is difficult for a single person to achieve stable positioning of the support bars. If the support bars lack flexibility, auxiliary tools such as clamps or spreader bars can be used to avoid material deformation or breakage caused by forced spreading.

2. Safety Protection Measures
   The welding process generates high temperatures, intense light, and harmful gases (such as metal oxide fumes). Operators must wear protective equipment:

• Gloves: To prevent burns from high-temperature splatter;
• Goggles: To filter intense light and ultraviolet rays, protecting the eyes;
• Ventilated Environment: Ensure air circulation in the work area to reduce the risk of inhaling harmful gases.

II. Special Requirements for Welding Processes of Bench Chairs

1. Heat Input Control
   Bench chair frames are mostly made of low-carbon steel or stainless steel tubes/plates. During welding, heat input must be controlled:

• Moderate heat input combined with multi-layer and multi-pass welding: Avoid excessive heat input leading to large weld penetration, metal overheating, and welding deformation after cooling; or insufficient heat input resulting in poor fusion and internal defects such as lack of fusion or porosity in the weld.

2. Selection of Fillet Weld Size
   The connection between the legs and crossbeams of bench chairs is mostly a fillet weld. The fillet weld size must be determined based on stress calculations:

• Generally, take 0.7 to 1.0 times the thickness of the thinner plate as the fillet weld height to ensure connection strength while avoiding material waste.

3. Optimization of Welding Sequence
   Bench chair frames are mostly symmetrical structures. The welding sequence should follow the following principles:

• Weld symmetrically from the middle to both ends: Or use the skip welding method to ensure uniform overall deformation and reduce structural distortion caused by uneven local heating.

III. Post-Welding Treatment and Quality Assurance

1. Annealing Treatment
   Some factories perform overall heat treatment (annealing) on welded bench chairs:

• Temperature Control: 600 to 650 degrees Celsius;
• Holding Time: Calculated as 1 to 2 minutes per millimeter of plate thickness to eliminate residual stress and prevent cracking during long-term use.

2. Surface Treatment

• Cleaning of Weld Slag and Splatter: Use tools to remove impurities from the weld surface;
• Grinding Treatment: Achieve a surface roughness below Ra3.2 micrometers to improve coating adhesion;
• Coating Anti-Corrosion Layer: Prevent metal oxidation and corrosion, extending service life.