1. Receive drawings and create production plan
- ・Receive design drawings from engineering department or clients.
- ・Develop shop drawings and detailed fabrication drawings.
- ・Create production plan and assign tasks to teams and machines.
2. Prepare materials and inspect incoming items
- ・Select correct materials: steel plates, profiles (H, I, U, V, pipes, boxes), bolts, base plates, etc.
- ・Check material certificates (CO, CQ).
- ・Measure dimensions, warpage, rust, etc.
- ・Preliminary cleaning: remove rust, oil, and impurities if any.
3. Steel cutting
- ・Cut steel according to drawings using oxy-gas, CNC plasma, or laser machines.
- ・Ensure dimensions are within allowable tolerances (usually ±1 mm).
- ・Mark and classify parts after cutting.
4. Mechanical machining of parts
- ・Drill or punch holes for bolts and base plates using CNC drilling or punching machines.
- ・Bevel and clean edges to prepare for welding.
- ・Bend parts if special shapes are required (hydraulic press).
5. Assembly and welding
- ・Pre-assemble parts according to drawings: beams, columns, purlins, base plates, etc.
- ・Tack weld to fix parts temporarily.
- ・Complete welding by manual arc or CO2 (MAG/MIG) according to approved WPS.
- ・Inspect welds (VT, MT, UT if required).
6. Surface cleaning
- ・Clean surface by sandblasting or rust-removing gun to SA 2.0 – SA 2.5 standard.
- ・Ensure proper surface roughness before painting.
7. Protective painting
- ・Apply anti-rust primer, usually epoxy or alkyd.
- ・Apply topcoat as per design color.
- ・Check paint thickness with specialized device.
- ・Ensure adhesion, thickness, and aesthetics meet standards.
8. Inspection and acceptance
- ・Check dimensions, tolerances, squareness, and warpage.
- ・Inspect weld quality and paint thickness.
- ・Attach label or part number if applicable.
- ・Internal inspection and acceptance with investor/supervisor.
9. Packaging and delivery
- ・Package steel parts using wire, pallets, or containers.
- ・Attach quality documents, drawings, CO/CQ if applicable.
- ・Arrange and transport to site according to plan.
