Industrial Production Process of Steel Structure Products

1. Project Planning & Design Phase

1.1 Design Parameter Standardization

• Load calculations: Wind load (0.5-1.5kN/m² per GB 50009), seismic grade (6-8度设防)
• Connection design: Bolted joints (10.9S grade) with slip factor ≥0.35
• Modeling software: Tekla Structures (公差±0.1mm), BIM collision detection

1.2 Material Specification

• Steel plate selection:
  • Thickness range: 6-100mm (Q355B yield strength ≥355MPa)
  • Zinc coating: 275g/m² for C3 corrosion environment
• Supplementary materials:
  • Welding wire: ER50-6 (AWS A5.18 standard)
  • Paint systems: 3-coat epoxy-polyurethane (DFT 280μm)

2. Precision Manufacturing Process

2.1 Cutting Technology Matrix

Method	Tolerance	Kerf Width	Application
Plasma	±1.2mm	3-5mm	Thickness >25mm
Laser	±0.3mm	0.2-1mm	Precision joints
Waterjet	±0.5mm	0.8-1.2mm	Composite materials

2.2 Welding Quality Control

• Procedure qualification:
  • Preheat temp: 100-150℃ (t≥25mm)
  • Interpass temp: ≤230℃
• NDT methods:
  • UT: Level B scanning (defect ≤Φ3mm)
  • RT: Class II per EN ISO 5817

3. Automated Assembly System

3.1 Robotic Fabrication

• Positioning accuracy: ±0.05mm (6-axis robots)
• Clamping force: 5-20kN (vacuum/pneumatic)
• In-process inspection: 3D laser scanning (0.02mm resolution)

3.2 Modular Construction

• Unit weight limit: ≤50 tons (road transport)
• Interface tolerance:
  • Bolt holes: ±1.0mm
  • Shear connectors: ±2mm vertical

4. Advanced Coating Process

4.1 Surface Preparation

• Blasting profile:
  • Angular anchor pattern (40-75μm)
  • Soluble salt limit: ≤20mg/m² NaCl
• Environmental controls:
  • Air dew point: ≤3℃ above substrate
  • Relative humidity: 40-60%

4.2 Curing Parameters

• Infrared curing:
  • Peak metal temp: 80-100℃
  • Exposure time: 8-12 minutes
• Adhesion test: ≥5MPa (ISO 4624 cross-cut)

5. Digital Quality Assurance

5.1 IoT Monitoring

• Weld tracking:
  • Arc voltage: 28±2V
  • Wire feed speed: 8-12m/min
• Coating thickness:
  • Continuous measurement (XRF technology)
  • Data logging per ISO 19840

5.2 Blockchain Documentation

• Material traceability:
  • QR code tracking (from mill to site)
  • Automated MTC verification
• Non-conformance management:
  • RFID tagging for quarantine parts
  • Automated alert system