Welding and Metal Fabrication in China — Buyer's Guide
China's metal fabrication industry ranges from small job shops doing structural steel welding to tier-1 automotive suppliers running robotic MIG welding lines. The challenge for buyers is finding the right fabricator for their quality requirements and volume.
Common Welding Processes
MIG/MAG Welding (GMAW)
Most common process in Chinese shops. CO2 or Ar-CO2 mix for steel, stainless, and aluminum.
- Automation: Hand-held to fully robotic (Fanuc, ABB, Panasonic)
- Specs: AWS D1.1 (steel), D1.2 (aluminum)
TIG Welding (GTAW)
For high-quality, cosmetic-critical joints. Slower with superior control.
- Applications: Sanitary tubing, aerospace, thin-wall stainless
- Specs: ASME Section IX, AWS D10.18M
Resistance Spot Welding (RSW)
Two copper electrodes clamp and pass current through overlapping sheets. Widely used in automotive.
- Sheet thickness: 0.5-3.0mm steel, 0.5-2.0mm aluminum
Laser Welding
Fiber lasers (1-8 kW) for precision welding with minimal heat-affected zone.
- Applications: Hermetic sealing, battery tab welding, micro-electronics
Materials Fabricated in China
| Material | Grades | Applications |
|---|
| Carbon Steel | Q235B, Q345B, A36, S355 | Structural steel, machinery frames |
| Stainless Steel | 304/L, 316/L, 2205 duplex | Food/pharma equipment, tanks |
| Aluminum | 5052, 5083, 6061 | Transportation, marine |
| Galvanized Steel | DX51D, SGCC | Enclosures, roofing |
Key Fabrication Clusters
- Foshan (Guangdong): Sheet metal and structural fabrication hub.
- Kunshan / Suzhou (Jiangsu): High-end automotive, medical, electronics.
- Ningbo (Zhejiang): Boiler and pressure vessel fabrication.
- Qingdao (Shandong): Heavy steel fabrication.
Certifications
- ISO 3834-2 (fusion welding quality)
- EN 1090 EXC1-EXC4 (European structural steel)
- AWS D1.1/D1.6 (US structural)
- ASME Section VIII Div. 1 (pressure vessels)
- ISO 9712 (welder and NDT certification)
Quality Checklist
- WPS and WPQR for your materials
- Welder certificates (ISO 9606 or ASME IX)
- NDT capability: X-ray, UT, dye penetrant
- Jigs and fixtures for consistent fit-up
- Weld map for multi-weld assemblies
- Surface prep (sa2.5 blasting) before painting