Stainless Steel Storage Tank Technical Parameters

1.Material Standards

Main Materials:

• o 304/304L: General purpose, resists weak corrosion (nitric acid, organic acids), temperature range -196~400°C
• o 316/316L: Contains Mo (2.5%), resists chloride corrosion, suitable for food/pharmaceutical industries
• o 321: Contains Ti, resists intergranular corrosion, suitable for high temperatures (≤800°C)
• o Duplex 2205: High strength, resists chloride stress corrosion, suitable for marine environments

Surface Treatment:

• o Mechanical Polishing: Ra≤0.4μm (mirror finish), meets GMP clean requirements
• o Electropolishing: Ra≤0.2μm, for ultra-clean applications
• o Sandblasting: Ra=0.8~1.6μm, for industrial environments

2.Pressure Ratings

3.Wall Thickness Calculation

Formula (ASME VIII Div.1):

• Cylinder thickness t = (P × R) / (S × E - 0.6P) + C
• o P: Design pressure (Mpa)
• o R: Inner radius (mm)
• o S: Allowable stress (e.g., 304L@150°C=129 Mpa)
• o E: Weld joint efficiency (0.85~1.0)
• o C: Corrosion allowance (0~3 mm)

Typical Wall Thickness Reference (Vertical Tanks):

4.Functional Configurations

Heat Transfer Structures:

• o Jacket Types: Half-pipe jacket (pressure ≤2.5 Mpa), full jacket (pressure ≤0.6 Mpa)
• o Coil Types: Internal spiral coil (heat transfer area 0.5~50 m²)

Agitation Systems:

• o Top-Entry Agitator: Power 0.75~55 kW, speed 50~300 rpm
• o Side Agitator: For high-viscosity materials (viscosity ≤50,000 cP)

Instrument Interfaces:

• o Level Gauges: Radar type (accuracy ±1mm), magnetic flap (visible range)
• o Temperature Probes: PT100 (accuracy ±0.1°C)
• o Pressure/Vacuum Relief Valves: Pressure setting range -0.5~+1.5 kPa

5.Special Design Options

Sanitary Design (3-A/BPE Standards):

1. o Internal radius R≥10mm, dead-leg free design
2. o Quick-opening manways (DN400~500), CIP/SIP capability

Corrosion Enhancement:

1. o PTFE lining/Halar coating (resists strong acids)
2. o Cathodic protection (for seawater tanks)

Insulation Structure:

1. o Polyurethane foam (thickness 50~100mm), stainless steel outer cladding

6. Quality Control

Non-Destructive Testing:

1. o Radiographic testing (RT): 100% testing of butt welds
2. o Penetrant testing (PT): Testing of all surface welds

Certifications:

1. o Material Certificates: EN 10204 3.1
2. o Pressure Vessel Certifications: ASME U Stamp/PED CE Mark

7.Selection Process

1. 1.Determine medium properties (corrosiveness, viscosity, solid content)
2. 2.Calculate volume and operating conditions (temperature, pressure, turnover frequency)
3. 3.Select material and surface finish grade
4. 4.Determine additional functions (agitation, heat transfer, etc.)
5. 5.Verify installation conditions (vertical/horizontal, support method)