Carbon Steel Storage Tanks

Standards & Compliance

Our carbon steel storage tanks are designed, fabricated, and tested in strict accordance with major international codes and standards. This ensures structural integrity, operational safety, and full regulatory compliance for your project.

1. Design & Fabrication Codes

We manufacture tanks to meet the specific pressure and temperature requirements of your application:

2. Material Standards

All raw materials (steel plates, flanges, pipes) are traceable and comply with recognized international standards:

Carbon Steel Plates: ASTM A36, ASTM A516 Gr.70, ASTM A283, Q235B, Q345R.

Stainless Steel (for cladding or internal parts): ASTM A240 (304, 316L).

Structural Steel (for platforms and ladders): ASTM A36 or equivalent.

3. Welding & Testing Standards

Our welding procedures and quality control systems strictly follow the relevant codes:

Welding Procedures (WPS/PQR): Qualified according to ASME Section IX.

Non-Destructive Testing (NDT): Radiographic Testing (RT), Ultrasonic Testing (UT), and Magnetic Particle Testing (MT) on critical shell and bottom welds.

Leak Testing: Hydrostatic testing (water fill) and Pneumatic testing as per API 650 / ASME requirements.

Third-Party Inspection: SGS, BV, TÜV, and Intertek are fully supported.

Materials & Corrosion Protection

The longevity and safety of a storage tank depend on the correct selection of steel grades and the application of appropriate corrosion protection systems. We provide comprehensive material and coating solutions tailored to the specific fluid, temperature, and environmental conditions of your project.

1. Base Steel Plate Materials

We use high-quality carbon steel plates with certified mill test reports (MTC) to ensure structural integrity and pressure resistance.

ASTM A36: The industry standard for general structural carbon steel, ideal for atmospheric tanks and water storage.

ASTM A516 Gr.70: High-strength, fine-grain carbon steel specifically designed for moderate and low-temperature pressure vessel services.

Q235B / Q345R: High-quality Chinese standards widely used for general liquid storage and pressure vessels, offering excellent weldability and cost-effectiveness.

Stainless Steel Cladding: For highly corrosive media, the carbon steel shell can be internally clad with 304 or 316L stainless steel.

2. Internal Corrosion Protection

For storing corrosive chemicals, acids, or pure water, we apply specialized internal linings to prevent chemical attack and contamination.

Epoxy Coating: Excellent resistance to mild acids, alkalis, and water (commonly used in potable water and food-grade tanks).

Glass-Flake Lining: High-build coating providing exceptional resistance to harsh chemicals, solvents, and seawater.

Rubber Lining: Ideal for highly aggressive acids (e.g., hydrochloric or sulfuric acid) in chemical processing.

3. External Corrosion Protection

To withstand harsh outdoor weather conditions, UV exposure, and industrial atmospheres, we apply a multi-layer external coating system.

Surface Preparation: Sandblasting to Sa 2.5 (near-white metal) to ensure maximum coating adhesion.

Coating System: Epoxy zinc-rich primer (anti-rust) + Epoxy intermediate coat + Polyurethane topcoat (UV-resistant and weather-proof).

Hot-Dip Galvanizing: Available for specific structural components (like ladders and platforms) for long-term outdoor protection.

4. Thermal Insulation

For tanks storing liquids that must be kept hot (e.g., heavy fuel oil, asphalt) or cold, we provide insulation systems.

Insulation Materials: Rock wool, Polyurethane (PU) foam, or Aerogel.

Cladding: Aluminum or stainless steel jacketing to protect the insulation from moisture and mechanical damage.

Manufacturing Process

The reliability of a carbon steel storage tank depends on strict fabrication procedures. We follow a controlled manufacturing process—from raw steel plate selection to final hydrostatic testing—to ensure the tank meets API 650 and ASME standards.

Step 1: Material Preparation & Cutting

Steel Plate Cutting: We use CNC plasma cutting or flame cutting machines to precisely cut the carbon steel plates according to the tank design.

Edge Preparation: Plate edges are beveled to ensure proper weld penetration and joint integrity.

Step 2: Plate Rolling

Cylindrical Shell: Large-scale rolling machines are used to cold-roll the steel plates into precise cylindrical shapes (shell sections).

Curvature Check: The rolled plates are inspected using templates to ensure they meet the exact radius required for the tank diameter.

Step 3: Automated Welding

Shell Longitudinal & Circumferential Seams: We use Automatic Submerged Arc Welding (SAW) for the main shell and bottom seams, ensuring deep penetration, uniform weld beads, and leak-free joints.

Nozzle & Manway Welding: Precision welding is used for the installation of nozzles, manways, and reinforcement pads.

WPS/PQR Compliance: All welding procedures are strictly qualified under ASME Section IX.

Step 4: Non-Destructive Testing

Weld Inspection: Critical welds are tested using Radiographic Testing (RT), Ultrasonic Testing (UT), and Magnetic Particle Testing (MT).

PMI (Positive Material Identification): To verify the chemical composition of the steel and the welding consumables.

Step 5: Hydrostatic & Leak Testing

Hydrostatic Test: The tank is filled with water to test for structural integrity and leak-proof performance.

Pneumatic Test: For tanks where water testing is not feasible, a pneumatic (air) test is performed with soap bubble solution.

Step 6: Surface Preparation & Coating

Sandblasting: The entire tank surface is sandblasted to Sa 2.5 (near-white metal) to remove rust and mill scale.

Painting/Lining: Application of internal linings (epoxy, rubber) and external topcoats (polyurethane, zinc-rich primer) as per project specifications.

Step 7: Knock-Down (KD) Packing

Disassembly: For large-capacity tanks, the shell sections, nozzles, ladders, and roof plates are disassembled.

Packing: All components are securely bundled with steel strips and wrapped in waterproof paper, optimized for FCL ocean freight.

1. How do you handle the shipping of large storage tanks?
For large-capacity tanks, we ship them in Knock-Down (KD) form. The shell plates, roof, nozzles, and structural components are disassembled, bundled, and packed securely. This drastically reduces ocean freight costs. We provide detailed erection drawings, and our engineers can guide the on-site assembly if required.

2. What design standards do you comply with?
Our tanks are designed and manufactured in strict accordance with international codes. We primarily build to API 650 (for atmospheric oil/water storage), ASME Section VIII Div.1 (for high-pressure vessels), and AWWA D100 (for municipal water storage). We also provide full Mill Test Certificates (MTC) for all steel plates.

3. Can you provide internal and external corrosion protection?
Yes. We offer comprehensive coating systems based on the stored media:

Internal: Epoxy coating, glass-flake lining, or rubber lining for corrosive chemicals and acids.

External: Sandblasting to Sa 2.5, followed by an epoxy zinc-rich primer and a UV-resistant polyurethane topcoat.

Insulation: Rock wool or polyurethane (PU) with aluminum jacketing for temperature maintenance.

4. What accessories can you supply with the tank?
We supply a complete range of tank accessories to ensure a turnkey solution, including:

Manways, flanges, and customized nozzles.

Ladders, platforms, and handrails.

Level gauges and liquid level sensors.

Vents, flame arrestors, and heating coils.

5. What information do I need to provide to get a quotation?
To provide an accurate CIF or FOB quotation, please provide:

Capacity/Volume (in m³).

Stored medium (e.g., water, diesel, acid) to determine the material and coating.

Design pressure and temperature.

Orientation (Vertical or Horizontal).

Destination port.

6. What are your payment terms and delivery time?

Delivery Time: Typically 30 to 45 days, depending on the order quantity and customization level.

Payment Terms: T/T, L/C, O/A, D/P.

Packing: All components are wrapped in waterproof paper and secured with steel strips for safe FCL transportation.