Views: 0 Author: Site Editor Publish Time: 2024-10-30 Origin: Site
Custom stainless steel tanks are widely used in food, chemical, pharmaceutical, energy and other fields, and their design needs to comply with industry standards and specific working conditions. The following are general specifications and important considerations for stainless steel tank design:
1. Design basis
Standards and specifications
GB 150 "Pressure Vessels"
GB/T 25198 "Technical Conditions for Non-Metallic Lined Equipment"
ASME VIII "Boiler and Pressure Vessel Code"
GB/T 3280 "Stainless Steel Cold-Rolled Steel Plate and Strip"
FDA (food industry related) or GMP (pharmaceutical industry related) specifications
Application scenarios and process requirements
Working medium (corrosive, toxic, flammable)
Temperature and pressure range
Whether stirring, heating or cooling functions are required
2. Stainless steel material selection
Common stainless steel grades
304: Suitable for normal temperature and non-strongly corrosive environments, such as food processing.
316L: Stronger corrosion resistance, suitable for the pharmaceutical and chemical industries.
310S: High temperature oxidation resistance, used for heating conditions.
Material thickness
Select according to tank capacity, pressure level, corrosion resistance and structural strength.
Pressure tanks usually use 510 mm thick stainless steel plates, and ordinary storage tanks can be 35 mm thick.
III. Structural design
Tank type
Vertical tank: commonly used for large-capacity storage or gravity separation.
Horizontal tank: suitable for transportation or narrow space.
Cylindrical tank: evenly distributed stress, more common.
Tank assembly
Top cover and bottom cover: usually use elliptical head or conical head to reduce weld concentration stress.
Legs or brackets: designed as saddle support, ring support or leg support according to the site environment.
Flange and manhole: easy to connect and maintain. The manhole is generally about 500 mm in diameter.
IV. Process design
Mixing system (if necessary)
Select the appropriate type of stirring paddle according to the viscosity of the medium, such as screw belt type, anchor type, frame type, etc.
The stirring shaft adopts a sealing structure (such as mechanical seal) to avoid leakage.
Insulation or jacket design
Jacket: used to transfer heat (such as steam heating or cooling water cooling).
Insulation layer: use rock wool or polyurethane to reduce heat loss.
Welding process
Argon arc welding or laser welding is commonly used to ensure weld smoothness and corrosion resistance.
Welds need to be inspected for flaws (such as X-ray or ultrasonic testing).
V. Safety design
Safety valve and pressure gauge
Ensure that pressure can be released in case of overpressure.
The pressure gauge is installed in a position that is easy to observe.
Vent and drain port design
The drain port should be lower than the lowest point of the tank to ensure complete emptying.
An explosion-proof valve is installed at the exhaust port (if necessary).
Internal and external surface treatment
Polishing: Improve surface smoothness and reduce residue accumulation. Commonly used polishing is #320 or #400.
Acid pickling and passivation: Eliminate welding stress and improve corrosion resistance.
VI. Inspection and verification
Pressure test
Hydraulic pressure test or air pressure test to detect the sealing and pressure bearing capacity of the tank.
Cleaning validation (food, pharmaceutical field)
In accordance with GMP or FDA requirements, ensure that the tank can be completely cleaned without residue.
Nondestructive testing (NDT)
X-ray testing, ultrasonic testing, etc. are used to inspect key welds.
VII. Precautions
Environmental assessment: The expansion and contraction of the tank under different temperatures and humidity must be considered.
Anti-corrosion design: Select the appropriate lining or electrolytic polishing process according to the acidity and alkalinity of the medium.
Compliance with regulations and standards: For export products, they must comply with the relevant standards of the target market (such as ASME certification).