Processing flow of sheet metal and steel structure

Sheet metal fabrication transforms metal sheets into structural components through systematic processing. Below is the standardized workflow:

I. Material Preparation

1. Material Selection

   • Choose metals per design requirements:

     • Carbon Steel: Cost-effective, high strength (general structures)

     • Stainless Steel: Superior corrosion resistance (harsh environments)

     • Aluminum Alloy: Lightweight, high strength (aerospace/automotive)

   • Verify specifications: thickness, width, length (e.g., thicker plates for high-load components).

2. Material Inspection

   • Surface quality: Check for cracks, inclusions, or scale via visual/ultrasonic testing.

   • Validate chemical composition & mechanical properties (e.g., carbon content in steel, yield strength).

II. Cutting (Blank Preparation)

III. Bending

1. Press Brake Bending

   • Uses V-dies to form angles (e.g., 90° bends for enclosures).

2. CNC Bending

   • Automated multi-stage bending for complex geometries (e.g., chassis components).

IV. Welding

Process Control:

• Pre-weld cleaning (remove oil/rust)

• Optimize parameters: current, voltage, travel speed

• Post-weld slag removal

V. Surface Treatment

1. Grinding: Remove burrs/weld seams (e.g., smoothing joints).

2. Painting: Enhance corrosion resistance & appearance (e.g., enclosure coating).

3. Plating: Zinc/chrome electroplating for critical corrosion protection (e.g., hardware fixtures).

VI. Assembly & Adjustment

• Fit components per engineering drawings (e.g., assembling enclosure panels).

• Functional testing: Verify kinematics/structural integrity (e.g., door operation).

VII. Quality Inspection

1. Dimensional Check

   • Tools: Calipers, micrometers, gauge blocks

   • Tolerance verification (e.g., enclosure dimensions).

2. Performance Validation

   • Load testing (structural strength)

   • Salt spray tests (corrosion resistance).

1. Cosmetic Audit

   • Surface defects: scratches, paint uniformity.

VIII. Packaging & Shipping

• Packaging: Wooden crates (large parts) with foam cushioning; cartons (small components).

• Transport: Road (short-haul), rail/ocean (long-distance).