Corrugated Metal Tanks Selection Guide
Optimizing Storage Solutions for Durability, Capacity & Cost-Effectiveness
1. Material & Corrosion Protection
Select based on stored medium and environment:
- Galvanized Steel (G235):
- Applications: Potable water, stormwater retention, agricultural slurry.
- Protection: Standard zinc coating (Z275+). Suitable for pH-neutral environments.
- Aluminized Steel Type 2 (AZ150):
- Applications: Wastewater, industrial process water, high-humidity/saline atmospheres.
- Protection: Aluminum-silicon alloy coating resists oxidation & sulfides.
- Polymer-Coated Steel (e.g., CSPE/PVC):
- Applications: Aggressive chemicals (pH 2–12), mining leachate, corrosive soils.
- Protection: Dual-layer fusion-bonded coating (≥0.40 mm thick).
Key Consideration: Match coating to fluid corrosivity (ASTM A929) and atmospheric corrosivity (ISO 12944 C2–C5).
2. Structural Design & Dimensions
2. Structural Design & DimensionsBalance capacity needs with site constraints:
- Diameter Range: 1.5m (5ft) to 30m+ (100ft+)
- Height Range: Standard 3m–12m (10ft–40ft); engineered designs up to 20m (65ft).
- Profile:
- Deep-Corrugated (150×50 mm / 6×2 in): High ring stiffness for tall tanks.
- Shallow-Corrugated (68×13 mm / 2.67×0.5 in): Cost-effective for mid-height tanks.
- Capacity Calc:textCopy Code
Volume (m³) = π × (Diameter/2)² × Height
- Design Standards: ASTM A760 (material), AWWA D103 (fabrication), EN 10245 (EU).
3. End Configurations & Roof Systems
Adapt to functional requirements:
- Base Options:
- Flat Bolted Floor: For granular/stable foundations.
- Concrete Slab Foundation: Required for fluid-tight integrity.
- Roof Types:
- Open-Top: For non-volatile liquids (e.g., irrigation).
- Cone Roof (Self-Supporting): Standard for rainwater/firewater storage.
- Flat Roof (Supported): Requires internal columns; allows roof access.
- Fixtures:
- Access hatches (OSHA-compliant), vents, overflow pipes, level gauges.
4. Geotechnical & Foundation Requirements
Ensure long-term stability:
- Soil Bearing Capacity: ≥ 100 kPa (2,000 psf) for tanks <10m diameter.
- Foundation Types:
- Compacted Granular Pad: 300mm min. thickness (for small tanks).
- Reinforced Concrete Ringwall: Essential for tanks >8m diameter.
- Settlement Tolerance: Max differential settlement ≤ 1:500 (per AWWA D103).
- Anchorage: Anchor bolts (ASTM F1554) required in seismic/windy zones.
5. Applications & Industry-Specific Considerations
| Application | Critical Design Factors |
|---|---|
| Potable Water | NSF/ANSI 61 certification, full-weld seam inspection. |
| Firewater Storage | UL/FM approval, seismic design (IBC/ASTM E2026). |
| Agricultural Slurry | Abrasion-resistant coating, conical floor for drainage. |
| Industrial Process | Lining compatibility (e.g., epoxy for chemicals). |
| Stormwater Harvesting | Debris exclusion screens, overflow bypass. |
6. Fabrication & Installation Methods
- Spiral-Rib Technology:
- On-site continuous helical winding for large diameters (>6m).
- Advantages: No horizontal seams, faster installation.
- Bolted Panel Systems:
- Shop-fabricated curved panels (1.2m–2.4m wide).
- Advantages: Transportable, flexible height adjustments.
- QA/QC:
- Seam testing (vacuum/air pressure), coating thickness verification.
7. Corrosion Management & Lifespan
- Design Life: 30–50 years (depending on coating/environment).
- Cathodic Protection (ICCP):
- Recommended for tanks in corrosive soils (resistivity <5,000 Ω·cm).
- Lining Systems:
- Spray-applied polyurea/coal tar epoxy for internal corrosion control.
- Inspection: Ultrasonic thickness testing every 5–10 years.
8. Cost-Benefit Analysis
| Factor | Corrugated Metal Tank | Concrete Tank | Polyethylene Tank |
|---|---|---|---|
| Installation Time | 40% faster | Slow (curing required) | Fast (but size-limited) |
| Material Cost | $$$ | $$$$ | $$ |
| Lifespan | 30–50 years | 50+ years | 15–25 years |
| Expansion Flexibility | Easily modifiable | Difficult | Not feasible |
Selection Checklist
- Fluid Type: pH, temperature, abrasiveness.
- Capacity Needed: Total volume, peak drawdown rate.
- Site Conditions: Soil report, seismic zone, wind loads.
- Regulatory: NSF, UL/FM, local codes.
- Accessories: Roof type, manways, mixers, level sensors.
- Supplier Qualifications: AWWA D103 certified fabricator.
