Pressure Vessels
A pressure vessel is a closed container designed to safely hold gases or liquids at a pressure different from atmospheric pressure.
They are widely used in industries like oil & gas, chemical, power plant, refrigeration, and food processing.
Main Parts of a Pressure Vessel
Shell – Main cylindrical body holding pressure
Heads (End Caps) – Close the vessel ends (dished or hemispherical)
Nozzles – Inlet and outlet connections
Flanges – For assembly and maintenance
Supports – Saddle, skirt, or legs for mounting
Types of Pressure Vessels
Horizontal vessel – Used for storage and separation
Vertical vessel – Used in reactors and towers
Spherical vessel – Used for high-pressure gas storage
Heat exchanger vessel – Used for heating and cooling fluids
Design Considerations
Engineers calculate:
Design pressure
Design temperature
Material strength
Corrosion allowance
Weld efficiency
Safety factor
Materials Used
Carbon steel
Stainless steel
Alloy steel
Duplex steel (corrosive service)
Testing and Inspection
Before operation, pressure vessels are tested:
Hydrostatic test
Radiography test (RT)
Ultrasonic test (UT)
Dye penetrant test (PT)
Design Codes and Standards
Pressure vessels are manufactured as per safety standards:
ASME Section VIII
PED (Europe)
Indian Boiler Regulations (IBR)
TEMA (for exchanger vessels)
Simple Summary
A pressure vessel is a safety-critical equipment designed to store or process fluids under pressure.
Proper design, material selection, and testing are essential to prevent leakage or failure.