Pressure Vessel Codes & Standards
Different projects require different design codes, inspection requirements and documentation.
ChannelVessel works from the project design basis to define the applicable requirements for pressure vessels, process vessels and storage tanks — including design pressure and temperature, materials, welding, inspection, testing and documentation.
Defined before detailed engineering
Start With the Applicable Code — Not Just the Vessel Size
Two vessels with similar dimensions can require very different engineering and manufacturing routes. The applicable pressure vessel code or storage tank standard depends on where the equipment will be installed, what it will contain, the design pressure and temperature, the type of equipment, regulatory requirements and the end user's project specification.
ASME BPVC Section VIII
Commonly specified for pressure vessel projects requiring ASME design and construction rules.
The applicable division and project requirements influence design calculations, materials, fabrication, examination, testing and certification requirements.
Official ASME referencePED / EN 13445
For pressure equipment intended for applicable European projects, PED establishes the regulatory conformity framework, while EN 13445 provides technical rules for unfired pressure vessels.
The final conformity route depends on the equipment classification and project requirements.
Official PED referenceAPI 650 / API 620
API standards address storage tank applications rather than serving as substitutes for pressure vessel design codes.
API 650 is widely specified for welded aboveground storage tanks, while API 620 addresses large welded low-pressure storage tanks.
Official API standardsGB/T 150
GB/T 150 provides a major design framework for pressure vessel projects under applicable Chinese requirements.
Project execution may also involve additional regulatory, material, fabrication, inspection and safety requirements.
Official GB/T 150 referenceThese Standards Are Not Interchangeable
An ASME pressure vessel, an API storage tank and equipment designed for PED conformity do not follow the same engineering path. The correct starting point is therefore not “Which standard is better?” but “Which code and regulatory framework apply to this specific equipment and installation?”
Which Code Applies to Your Equipment?
Selecting the correct code begins with understanding what the equipment actually does. Pressure vessels, low-pressure storage tanks and atmospheric storage tanks do not follow the same engineering route, even when they look similar from the outside.
| Code / Standard | Typical Equipment | Primary Focus | Typical Project Question |
|---|---|---|---|
PRESSURE VESSELS
ASME Section VIII Division 1 | Pressure vessels, process vessels, separators, receivers, reactors and other pressure-containing equipment. | Design, fabrication, examination, inspection, testing and applicable certification requirements for pressure vessels. | Is the equipment operating under internal pressure, external pressure or both, and does the project specification require ASME construction? |
ALTERNATIVE RULES
ASME Section VIII Division 2 | Pressure vessels for projects using the alternative rules of Division 2. | A more detailed design approach that may involve different design methods, stress evaluation and engineering requirements. | Does the owner specification, operating condition or engineering basis specifically require Division 2? |
EUROPEAN PROJECTS
PED / EN 13445 | Pressure equipment intended for projects where European conformity requirements apply. | PED establishes regulatory requirements, while EN 13445 provides technical rules for unfired pressure vessels. | Where will the equipment be placed on the market, how is it classified, and what conformity assessment route applies? |
STORAGE TANKS
API 650 | Large welded aboveground storage tanks. | Tank design and construction for applicable atmospheric or near-atmospheric storage applications. | Is this fundamentally a storage tank project rather than a pressure vessel project? |
LOW-PRESSURE TANKS
API 620 | Large welded low-pressure storage tanks. | Storage applications operating at pressures beyond the typical scope of atmospheric storage tanks but within the applicable API 620 range. | Does the required storage pressure place the tank outside the normal API 650 design basis? |
CHINESE CODE BASIS
GB/T 150 | Pressure vessels for applicable projects using Chinese pressure vessel requirements. | Pressure vessel materials, design, fabrication, examination and related technical requirements. | Does the project require a Chinese code basis, local regulatory compliance or a specific owner-defined standard? |
A Design Code Changes More Than the Calculation
Selecting a code does not simply change a formula or required shell thickness.
It influences the engineering and manufacturing route from the first design input to the final documentation package. Materials, welding, inspection, testing and traceability all need to remain consistent with the approved project basis.
The code basis should be confirmed before detailed engineering and fabrication begin, because later changes can affect calculations, material selection, welding procedures, inspection scope and final documentation.
Design Basis
Engineering begins by defining the vessel type, design pressure, design temperature, corrosion allowance, loading conditions, operating cycles, vacuum conditions where applicable and other project-specific requirements.
These inputs determine which calculations and design checks are required.
Material Selection
Material selection must consider both the process medium and the applicable code.
Material grade, allowable properties, temperature limits, corrosion resistance, impact requirements where applicable and traceability all need to remain consistent with the project design basis.
Welding Qualification
Pressure-containing welds are not treated as ordinary fabrication welds.
Applicable welding procedures, procedure qualifications, welder qualifications, joint configuration and production controls need to be established before fabrication proceeds.
Inspection & NDE
Inspection requirements are defined according to the selected code and project specification.
The required examination method and extent should be confirmed during engineering rather than decided only after fabrication.
Pressure Testing
Hydrostatic or other applicable pressure testing forms part of the verification process.
The test method, test pressure, preparation, acceptance criteria and documentation depend on the applicable code, vessel configuration and project requirements.
Final Documentation
A vessel is not complete when fabrication ends.
The final documentation package should connect the approved design basis with the actual materials, welding, inspection and testing used during manufacturing.
That traceability is what turns individual manufacturing records into a coherent project file — and allows the purchaser, inspector and end user to verify how the vessel was engineered and manufactured.
Code Compliance Must Be Traceable
Passing a thickness calculation alone does not demonstrate that an entire pressure vessel project has been executed consistently with its specified code basis.
From Material Receipt to Final Vessel
The material entering the workshop, the welder performing the joint, the examination of the weld and the final pressure test all need to connect back to the approved engineering requirements.
A complete documentation package links approved drawings, materials, welding, inspection and testing into one traceable project record.
Engineering Documents
- Approved fabrication drawings
- General arrangement drawings
- Design calculations where required
- Nozzle orientation and connection details
- Design data and equipment specifications
Material Records
- Material certificates / MTRs
- Material identification
- Heat number traceability
- Component material records
- Applicable material verification records
Welding Records
- Welding Procedure Specifications
- Procedure Qualification Records
- Welder qualification records
- Welding traceability where required
- Heat treatment records where applicable
Inspection Records
- Dimensional inspection
- Visual inspection
- NDE reports
- Third-party inspection records where required
- Customer inspection and hold-point records
Testing & Final Records
- Pressure test reports
- Final inspection records
- Nameplate and marking information
- Applicable certificates
- Manufacturing data documentation
- Final document package specified by the project
Define the Code Basis Before We Quote
The earlier the code basis is defined, the more accurately a vessel can be engineered, priced and scheduled. A quotation based only on diameter and capacity can overlook requirements that substantially affect the final vessel.
Where will the equipment operate?
Country and installation location can affect the applicable regulatory framework and conformity requirements.
What are we designing?
Pressure vessel, reactor, separator, receiver, heat exchanger, process vessel, storage tank or another type of equipment.
What pressure cases must the vessel withstand?
Provide maximum design pressure and any external-pressure or full-vacuum conditions.
What temperature range must be considered?
Provide minimum and maximum design temperatures where known.
What will be inside the vessel?
Fluid composition, corrosiveness, cleanliness requirements and relevant process hazards can influence material and design decisions.
Has the project specification already named a code?
Examples may include ASME BPVC, PED / EN standards, API standards, GB/T requirements or an owner-specific engineering specification.
What level of inspection is required?
Specify NDE requirements, third-party inspection, customer witness points or other inspection requirements if already defined.
What must be submitted with the vessel?
Different purchasers and end users may require different drawings, certificates, reports and manufacturing records.
Send the available project information even if the specification is not complete.
We can review the design basis first and identify the information that still needs to be defined before manufacturing.