High-Corrosion Resistant Aluzinc Steel Silo Solutions
- Typical Aplications: Suitable for high-temperature areas, tropical climate silos, biomass pellet storage, feed processing plants, outdoor long-term storage, and industrial bulk storage, etc.
As a turnkey storage silo manufacturer, we create customized storage systems using steel that is tailored to the environment, storage material, structural loads, and the design life of the system.
From inland grain storage to heavy-duty marine and chemical use, we provide structural configurations and coating specifications that are customized for the ideal durability, safety, and value throughout the service life.
Hot-Dip Coating with Metallurgical Bond for Long-Term Corrosion Protection
The coating is created through a continuous hot-dip process that forms a metallurgical bond to the steel, as opposed to a simple surface paint film. This bond offers the stable and durable protection that is required for turnkey industrial storage systems that operate outdoors and in corrosive environments.
Galvalume Steel Silo Crane Lifting Construction
Galvalume Steel Silo Ladder Installation
Galvalume Steel Spiral Silo Construction Site
Galvalume Steel Spiral Silo Body Rolling
Why choose Galvalume Coating for Silo Steel?
Galvalume steel is a premium coated steel that is favored for use in industrial storage silos and related applications. This steel is alloyed with aluminum and zinc and offers a highly durable corrosion resistant coating that, in addition to reflective heat, is also sacrificial. For custom storage silo systems, Galvalume steel strikes an ideal balance of performance and cost throughout the system’s service life.
Typical Composition of Galvalume Coating Steel Sheet:
| Element | Composition | Typical Ratio |
|---|---|---|
| Aluminum | Aluminum | 55% |
| Zinc | Zinc | 43.4% |
| Silicon | Silicon | 1.6% |
Barrier protection and heat reflection of the coating is due to the 55% aluminum, while the zinc facilitates coating integrity through sacrificial protection of areas that are corroded or otherwise damaged. Silicon enhances adhesion of the coating.
Functions of Galvalume Coating in Storage Silo Applications
Steel Silo Galvalume Steel Roofing And Wall Panel Protection System Diagram
Moisture, oxygen, and corrosive media are prevented from coming into contact with steel substrates by an aluminum-rich coating which creates a dense, protective barrier.
Compared to most galvanized steel, Galvalume sustains a lower rate of heat absorption and then consequently minimizes thermal expansion when exposed to prolonged direct sunlight.
When Galvalumed steel is scratched during shipping or installation, the zinc layer continues to protect the steel substrate from corrosion.
Corrosion at the cut edges or holes is usually the point of failure for most steel structures. In outdoors storage silo systems, the zinc layer improves corrosion resistance at cut edges and enhances the system’s overall lifespan.
Galvalume Steel Manufacturing Process for Industrial Silo
- Raw Coil Preparation
To facilitate the continuous feeding of steel strips, low-carbon cold-rolled steel coils are uncoiled and joined end to end.
- Surface Pretreatment
To create a clean steel surface for coating, oil and oxides are removed by degreasing, brushing, and rinsing followed by a hot air dry.
- Annealing and Reduction
Heating of steel strips occurs in an oxidizing atmosphere with reduced hydrogen, facilitating coating adhesion and forming of the steel with improved surface treatment.
- Hot-Dip Aluminum-Zinc Coating
A coating layer resulting from a metallurgical bond is formed when steel strips are immersed in a molten alloy of 55% aluminum, 43.4% zinc, and 1.6% silicon.
- Air Knife Coating Control
Air knives operated at high pressure control the weight and thickness of a coating, resulting in the consistent grading of AZ100, AZ150, AZ180, and AZ200+.
- Cooling and Surface Treatment
Flatness treatment techniques quickly cool the metal and apply a skin pass, along with a treatment of passivating oils; All of which result in higher surface flatness, greater surface passivation, and improved fabricability characteristics.
- Inspection and Finishing
Before the metal is recoiled and stored, online inspection systems check adhesion, thickness, and uniformity of the coating.
How to Select the Right Galvalume Coating Grade
Common Galvalume Coating Grades:
| Coating Grade | Coating Weight | Protection Level | Typical Applications |
|---|---|---|---|
| AZ100 | 100 g/m² | Light-duty protection | Dry inland storage |
| AZ150 | 150 g/m² | Standard in | Grain and feed silos |
| AZ180 | 180 g/m² | Heavy outdoor protection | Coastal and humid environments |
| AZ200+ | ≥200 g/m² | Extreme corrosion resistance | Marine and chemical projects |
Core Design Principle: Coating selection must balance fabrication performance and the overall cost of the project. Coating selection must not ignore excessively high specifications.
AZ100 for Dry Inland Environments
This grade is the first line of defense and is designed for the dry, humid, and corrosion free areas of the inland. Provides an economical coating for short to medium term storage.
AZ150 for Standard Industrial and Agricultural Storage
AZ150 provides an excellent balance of cost, corrosion protection, and forming performance and is the most typically specified coating for grain and feed silos and other industrial storage systems.
AZ180 for Humid Outdoor and Mild Coastal Conditions
This grade is for outdoor use in the rainy and humid environments and light coastal conditions. This grade provides long outdoor durability by improving protection for corrosion and the coating edge.
AZ200+ for Marine and Chemical Environments
This grade provides a heavier coating which improves protection against industrial corrosion and aggressive chemicals, and extends the service life of storage silos.
Quality Control for Galvalume Steel Storage Silo Manufacturing
Quality control must be a concerted effort for raw materials, coating processes, and the finished item, taking into consideration long term structural integrity and employee safety and concerns on operating the product.
- Base Steel Quality Control: Quality, cold rolled, low carbon steel is selected, with the steel sheet carefully evaluated for surface irregularities, as well as, dimensional and mechanical concerns that would result in failure during the forming, bending, and welding operations.
- Surface Pretreatment Control: Degreasing, rinsing, and drying are closely monitored to avoid surface defects and coating adhesion issues.
- Coating Composition and Thickness Control: The coating has 55% Al, 43.4% Zn, and 1.6% Si. An air-knife is used to maintain uniformity in coating and to provide grade-A performance for both surfaces of the steel sheet.
- Adhesion and Structural Performance Control: The brittle alloy layer is controlled by the optimizing the annealing operations to ensure integrity of the coating after bending, punching, and all other fabrication operations.
- Surface Quality Inspection: The surface of the steel sheet is carefully evaluated to ensure defects which would impact aesthetic appeal and integrity of the coating for corrosion protection are absent.
- Key Performance Testing: Typical evaluation items include the coating and interface adhesion, and salt spray test for coating and edge corrosion evaluation, and assessment of heat reflection performance.
- Post-Treatment Process Control: Passivation and oiling treatment enhance anti-fingerprint and moisture resistance while improving durability for outdoor exposure.
