Steel formwork, when properly maintained, can be reused hundreds of times, significantly reducing construction costs and ensuring consistent concrete quality. Based on industry best practices and technical standards, here are practical, actionable tips for maintaining and caring for steel formwork, organized into key operational phases.
1. Immediate Post-Use Cleaning: Prevent Buildup and Corrosion
- Clean while damp: Remove concrete residue immediately after stripping, while the surface is still slightly moist. This prevents hardening and makes cleaning easier.
- Use non-abrasive tools: Scrape off residue with wooden or plastic scrapers. Avoid metal hammers or chisels, which can dent or warp the panel.
- High-pressure water or specialized cleaners: For stubborn buildup, use high-pressure washers (300–350 bar) or chemical cleaning solutions in heated tanks (40°C), followed by neutralization with lime water and drying.
- Dry thoroughly: Ensure no moisture remains, especially in joints and recesses, to prevent rust initiation.
2. Rust Prevention: Coating and Storage Protection
- Apply anti-rust oil or paint: After cleaning and drying, coat all surfaces—especially the back, edges, and weld seams—with rust-inhibiting oil or epoxy-based anti-corrosion paint.
- Recoat when needed: Inspect regularly; if paint is chipped or peeled, sand the area and reapply promptly.
- For long-term storage: Apply a thicker layer of防锈油 (rust preventive oil) and cover with protective film to block moisture, particularly critical in humid climates like Tianjin.
3. Proper Storage: Avoid Deformation and Environmental Damage
- Indoor or covered storage: Store in a dry, ventilated warehouse or under a canopy. If outdoor storage is unavoidable, fully cover with waterproof tarpaulins or iron sheets.
- Use support pads: Place wooden blocks (at least 10 cm high) under the bottom layer to prevent ground moisture contact and ensure even load distribution.
- Stack correctly:
- Limit stack height to 6 layers or 2 meters, whichever is lower
- Align support blocks vertically across layers
- Tilt large panels at 45° with anti-toppling supports if stored vertically
- Organize by type: Sort by size and model, maintain inventory records, and avoid mixing different templates.
4. Regular Inspection and Maintenance: Catch Issues Early
- Check for deformation: Look for warping, bending, or twisting. Minor distortions can be corrected with a straightening machine or hydraulic press.
- Inspect connections: Ensure bolts, clamps, and welds are intact and tight. Replace damaged U-clips or threaded fasteners promptly.
- Monitor rust development: In high-humidity environments, inspect every 2–4 weeks. Studies show untreated steel can begin rusting within 3 months under damp conditions.
5. Safe Handling and Transportation: Prevent On-Site Damage
- Use proper lifting equipment: Employ cranes or forklifts with soft slings to avoid impact damage. Never drag or drop templates.
- Separate during transport: Do not mix different sizes. Use layered flat transport or vertical racks with padding between units.
- Secure loads: Fasten templates firmly to prevent shifting or collision during transit.
6. Repair and Refurbishment: Restore Performance
- Repair dents and warps: Use a straightening press or professional校平机 (flattening machine) instead of hammering, which can weaken the structure.
- Fix rusted areas: Completely remove rust with sandblasting or wire brushes, then apply primer and topcoat.
- Reinforce damaged sections: Weld in reinforcement plates for cracked or thinned areas, then grind smooth.
