The ASME Boiler & Pressure Vessel Code (BPVC) is an American Society of Mechanical Engineers (ASME) standard that provides rules for the design, fabrication, and inspection of boilers and pressure vessels. A pressure component designed and fabricated in accordance with this standard will have a long, useful service life, and one that ensures the protection of human life and property. Volunteers, who are nominated to its committees based on their technical expertise and on their ability to contribute to the writing, revising, interpreting, and administering of the document, write the BPVC. The American Society of Mechanical Engineers (ASME) works as an Accreditation Body and entitles independent third parties such as verification, testing and certification agencies to inspect and ensure compliance to the BPVC.
The BPVC was created in response to public outcry after several serious explosions in the state of Massachusetts. A fire-tube boiler exploded at the Grover Shoe Factory in Brockton, Massachusetts on March 20, 1905 which resulted in the deaths of 58 people and injured 150. Then on December 6, 1906 a boiler in the factory of the P.J. Harney Shoe Company exploded in Lynn, Massachusetts. As a result the state of Massachusetts enacted the first legal code based on ASME's rules for the construction of steam boilers in 1907.
ASME convened the Board of Boiler Rules before it became the ASME Boiler Code Committee which was formed in 1911. This committee put in the form work for the first edition of the ASME Boiler Code - Rules for the Construction of Stationary Boilers and for the Allowable Working Pressures, which was issued in 1914 and published in 1915.
The first publication was known as the 1914 edition, and it developed over time into the ASME Boiler and Pressure Vessel code, which today has over 92,000 copies in use, in over 100 countries around the world.
The first edition of the Boiler and Pressure Vessel Code (1914 edition) consisted of one book, 114 pages long, measuring 5 x 8 inches which evolved into today's edition which consists of 28 books, including twelve dedicated to the construction and inspection of nuclear power plant components and two Code Case books. (The 2001 edition of the Boiler and Pressure Vessel Code is more than 16,000 pages.) The 28 books are either standards that provide the rules for fabricating a component or they are support documents, such as Materials, Nondestructive Examination, and Welding and Brazing Qualifications.
After the first edition of the Code, the verifications that the manufacture was to the Code was performed by independent inspectors, which resulted in a wide range of interpretations. Hence in February 1919, the National Board of Boiler and Pressure Vessel Inspectors was formed.
The American Society of Mechanical Engineers is founded
First performance test code: Code for the Conduct of Trials of Steam Boilers
First revision of an ASME standard, Standard Method of Conducting Steam Boiler Tests
Establishment of a committee to propose a Boiler Code
New Committee to revise the Boiler Code
Issuance of the first Boiler Code
Standards for Specifications and Construction of Boilers and Other Containing Vessels in Which High Pressure is Contained
National Board of Boiler and Pressure Vessel Inspectors formed
Code for Unfired Pressure Vessels
Test Code of Complete Steam-Electric Power Plants
Committee established for ASME Pressure Vessel Code for Nuclear Age
Section III (Nuclear Power) of ASME Boiler and Pressure Vessel Code
ASME Nuclear Power Certificate of Authorization Program commences
ASME expands its certification program worldwide; first ASME manufacturer certification issued outside of North America
First ASME publication of Boiler and Pressure Vessel Committee interpretations
ASME Boiler and Pressure Vessel Code published in both conventional and metric units
Boiler and Pressure Vessel Code published on CD-ROM
First Authorized Inspection Agency accredited
Risk technology introduced into the Boiler and Pressure Vessel Code
High Pressure Vessel Code
C&S Connect (on-line balloting and tracking system) launched for Boiler and_Pressure Vessel Committees
ISO TC11 Standard 16528—Boilers and Pressure Vessels published, establishing performance requirements for the construction of boilers and pressure vessels and facilitating registration of BPV Codes to this standard
Polyethylene plastic pipe introduced into the Boiler and Pressure Vessel Code, Section III
ASME Boiler and Pressure Vessel Committee reorganized from one consensus body to ten consensus bodies
ASME BPVC Section VI - Recommended Rules for the Care and Operation of Heating Boilers
ASME BPVC Section VII - Recommended Guidelines for the Care of Power Boilers
ASME BPVC Section VIII - Rules for Construction of Pressure Vessels
Division 2 - Alternative Rules
Division 3 - Alternative Rules for Construction of High Pressure Vessels
ASME BPVC Section IX - Welding and Brazing Qualifications
ASME BPVC Section X - Fiber-Reinforced Plastic Pressure Vessels
ASME BPVC Section XI - Rules for Inservice Inspection of Nuclear Power Plant Components
ASME BPVC Section XII - Rules for the Construction & Continued Service of Transport Tanks
Addenda, which include additions and revisions to the individual Sections of the Code, are issued accordingly for a particular edition of the code up until the next edition.
ASME's interpretations to submitted technical queries relevant to a particular Section of the Code are issued accordingly. Interpretations are also available through the internet.
Code Cases provide rules that permit the use of materials and alternative methods of construction that are not covered by existing BPVC rules. For those Cases that have been adopted will appear in the appropriate Code Cases book: "Boilers and Pressure Vessels" and "Nuclear Components."
Codes Cases are usually intended to be incorporated in the Code in a later edition. When it is used, the Code Case specifies mandatory requirements which must be met as it would be with the Code. There are some jurisdictions that do not automatically accept Code Cases.
ASME BPVC Section II - Materials
The section of the ASME BPVC consists of 4 parts.
Part A - Ferrous Material Specifications
This Part is a supplementary book referenced by other sections of the Code. It provides material specifications for ferrous materials which are suitable for use in the construction of pressure vessels.
The specifications contained is this Part specify the mechanical properties, heat treatment, heat and product chemical composition and analysis, test specimens, and methodologies of testing. The designation of the specifications start with 'SA' and a number which is taken from the ASTM 'A' specifications.
Part B - Nonferrous Material Specifications
This Part is a supplementary book referenced by other sections of the Code. It provides material specifications for nonferrous materials which are suitable for use in the construction of pressure vessels.
The specifications contained is this Part specify the mechanical properties, heat treatment, heat and product chemical composition and analysis, test specimens, and methodologies of testing. The designation of the specifications start with 'SB' and a number which is taken from the ASTM 'B' specifications.
Part C - Specifications for Welding Rods, Electrodes, and Filler Metals
This Part is a supplementary book referenced by other sections of the Code. It provides mechanical properties, heat treatment, heat and product chemical composition and analysis, test specimens, and methodologies of testing for welding rods, filler metals and electrodes used in the construction of pressure vessels.
The specifications contained is this Part are designated with 'SFA' and a number which is taken from the American Welding Society (AWS) specifications.
Part D - Properties (Customary/Metric)
This Part is a supplementary book referenced by other sections of the Code. It provides tables for the design stress values, tensile and yield stress values as well as tables for material properties (Modulus of Elasticity, Coefficient of heat transfer et al.)
ASME BPVC Section III - Rules for Construction of Nuclear Facility Components
Section III of the ASME Code Address the rules for construction of nuclear facility components and supports. The components and supports covered by section III are intended to be installed in a nuclear power system that serves the purpose of producing and controlling the output of thermal energy from nuclear fuel and those associated systems essential to safety of nuclear power system. Section III provides requirements for new construction of nuclear power system considering mechanical and thermal stresses due to cyclic operation. Deterioration, which may occur in service as result of radiation effects, corrosion, or instability of the material, is typically not addressed.
Subsection NCA (General Requirements for Division 1 and Division 2)
NCA-1000 Scope of Section III
NCA-2000 Classification of Components and Supports
NCA-3000 Responsibilities and Duties
NCA-4000 Quality Assurance
NCA-5000 Authorized Inspection
NCA-8000 Certificates, Nameplates, Code Symbol Stamping, and Data Reports
Division 1- Metallic Components
Subsection NB Class 1 components (Those components that are part of the fluid-retaining pressure boundary of the reactor coolant system. Failure of this pressure boundary would violate the integrity of the reactor coolant pressure boundary)
Reactor Pressure Vessel
Reactor Coolant Pumps
Reactor Coolant Piping
Subsection NC Class 2 components (Those components that are not part of the reactor coolant pressure boundary, but are important for reactor shutdown, emergency core cooling, post-accident containment heat removal, or post-accident fission product removal)
Emergency Core Cooling
Post Accident Heat Removal
Post Accident Fission Product Removal
Includes Vessels, Pumps, Valves, Piping, Storage Tanks, and Supports
Subsection ND Class 3 components (Those components that are not part of class 1 or 2 but are important to safety)
Cooling Water Systems
Auxiliary Feedwater Systems
Includes Vessels, Pumps,Valves, Piping, Storage Tanks, and Supports
Subsection NE Class MC supports
Penetration Assemblies (Does not include piping, pumps and valves which if passing through thecontainment must be class 1 or class 2)
Subsection NF Supports
Plate and Shell Type
Support Class is the class of the Component Supported
Subsection NG Core Support Structures (class CS)
Core Support Structures
Reactor Vessel Internals
Subsection NH Class 1 Components in Elevated Temperature Service (Those components that are used in elevated temperature service)
ASME BPVC Section V - Nondestructive Examination
The section of the ASME BPVC contains the requirements for nondestructive examinations which are referred and required by other sections of the Code.
The section also covers the suppliers examination responsibilities, requirements of the authorized inspectors (AI) as well as the requirements for the qualification of personnel, inspection and examinations.
ASME BPVC Section VIII - Rules for Construction of Pressure Vessels
The section of the ASME BPVC consists of 3 divisions.
ASME Section VIII Division 1
This division covers the mandatory requirements, specific prohibitions and nonmandatory guidance for materials, design, fabrication, inspection and testing, markings and reports, overpressure protection and certification of pressure vessels having an internal or external pressure which exceeds 15 psi (100 kPa).
The pressure vessel can be either fired or unfired. The pressure may be from external sources, or by the application of heating from an indirect or direct source, or any combination thereof.
The Division is not numbered in the traditional method (Part 1, Part 2 etc.) but is structured with Subsections and Parts which consist of letters followed by a number. The structure is as follows:
Subsection A - General Requirements
Part UG - General Requirements for All Methods of Construction and All Materials
Materials: UG-4 through to UG-15
Design: UG-16 through to UG-35
Openings and Reinforcements: UG-36 through to UG-46
Braced and Stayed Surfaces: UG-47 through to UG-50
Fabrication: UG-75 through to UG-85
Inspection and Tests: UG-90 through to UG-103
Marking and Reports: UG-115 through to UG-120
Overpressure Protection: UG125 through to UG-140
Subsection B - Requirements Pertaining to Methods of Fabrication of Pressure Vessels
Part UW - Requirements for Pressure Vessels Fabricated by Welding
General: UW-1 through to UW-3
Design: UW-8 through to UW-21
Fabrication: UW-26 through to UW-42
Inspection and Tests: UW-46 through to UW-54
Marking and Reports: UW-60
Pressure Relief Devices: UW-65
Part UF - Requirements for Pressure Vessels Fabricated by Forging
Materials: UF-5 through to UF-7
Design: UF-12 through to UF-25
Fabrication: UF-26 through to UF-43
Inspection and Tests: UF-45 through to UF-55
Marking and Reports: UF-115
Pressure Relief Devices: UF-125
Part UB - Requirements for Pressure Vessels Fabricated by Brazing
General: UB-1 through to UB-3
Materials: UB-5 through to UB-7
Design: UB-9 through to UB-22
Fabrication: UB-30 through to UB-37
Inspection and Tests: UB-40 through to UB-50
Marking and Reports: UB-55
Pressure Relief Devices: UB-60
Subsection C - Requirements Pertaining to Classes of Materials
Part UCS - Requirements for Pressure Vessels Constructed of Carbon and Low Alloy Steels
Materials: UCS-5 through to UCS-12
Design: UCS-16 through to UCS-57
Low Temperature Operation: UCS-65 through to UCS-68
Fabrication: UCS-75 through to UCS-85
Inspection and Tests: UCS-90
Marking and Reports: UCS-115
Pressure Relief Devices: UCS-125
Nonmandatory Appendix CS: UCS-150 through to UCS-160
Part UNF - Requirements for Pressure Vessels Constructed of Nonferrous Materials
General: UNF-1 through to UNF-4
Materials: UNF-5 through to UNF-15
Design: UNF-16 through to UNF-65
Fabrication: UNF-75 through to UNF-79
Inspection and Tests: UNF-90 through to UNF-95
Marking and Reports: UNF-115
Pressure Relief Devices: UNF-125
Appendix NF: Characteristics of the Nonferrous Materials (Informative and Nonmandatory)
Part UHA Requirements for Pressure Vessels Constructed of High Alloy Steel
General: UHA-1 through to UHA-8
Materials: UHA-11 through to UHA-13
Design: UHA-20 through to UHA-34
Fabrication: UHA-40 through to UHA-44
Inspection and Tests: UHA-50 through to UHA-52
Marking and Reports: UHA-60
Pressure Relief Devices: UHA-65
Appendix HA: Suggestions on the Selection and Treatment of Austenitic Chromium–Nickel and Ferritic and Martensitic High Chromium Steels (Informative and Nonmandatory)
Part UCI - Requirements for Pressure Vessels Constructed of Cast Iron
General: UCI-1 through to UCI-3
Materials: UCI-5 through to UCI-12
Design: UCI-16 through to UCI-37
Fabrication: UCI-75 through to UCI-78
Inspection and Tests: UCI-90 through to UCI-101
Marking and Reports: UCI-115
Pressure Relief Devices: UCI-125
Part UCL - Requirements for Welded Pressure Vessels Constructed of Material With Corrosion Resistant Integral Cladding, Weld Metal Overlay Cladding, or With Applied Linings
General: UCL-1 through to UCL-3
Materials: UCL-10 through to UCL-12
Design: UCL-20 through to UCL-27
Fabrication: UCL-30 through to UCL-46
Inspection and Tests: UCL-50 through to UCL-52
Marking and Reports: UCL-55
Pressure Relief Devices: UCL-60
Part UCD - Requirements for Pressure Vessels Constructed of Cast Ductile Iron
General: UCD-1 through to UCD-3
Materials: UCD-5 through to UCD-12
Design: UCD-16 through to UCD-37
Fabrication: UCD-75 through to UCD-78
Inspection and Tests: UCD-90 through to UCD-101
Marking and Reports: UCD-115
Pressure Relief Devices: UCD-125
Part UHT Requirements for Pressure Vessels Constructed of Ferritic Steels With Tensile Properties Enhanced by Heat Treatment.
Materials: UHT-5 through to UHT-6
Design: UHT-16 through to UHT-57
Fabrication: UHT-75 through to UHT-86
Inspection and Tests: UHT-90
Marking and Reports: UHT-115
Pressure Relief Devices: UHT-125
Part ULW Requirements for Pressure Vessels Fabricated by Layered Construction
Introduction: ULW-1 through to ULW-2
Design: ULW-16 through to ULW-26
Welding: ULW-31 through to ULW-33
Nondestructive Examination of Welded Joints: ULW-50 through to ULW-57
Fabrication: ULW-75 through to ULW-78
Inspection and Tests: ULW-90
Marking and Reports: ULW-115
Pressure Relief Devices: ULW-125
Part ULT Alternative Rules for Pressure Vessels Constructed of Materials Having Higher Allowable Stresses at Low Temperature
General: ULT-1 through to ULT-5
Design: ULT-16 through to ULT-57
Fabrication: ULT-76 through to ULT-86
Inspection and Tests: ULT-90 through to ULT-100
Marking and Reports: ULT-115
Pressure Relief Devices: ULT-125
Part UHX - Rules for Shell-and-Tube Heat Exchangers
Part UIG - Requirements for Pressure Vessels Constructed of Impregnated Graphite
General: UIG-1 through to UIG-3
Materials: UIG-5 through to UIG-8
Design: UIG-22 through to UIG-60
Fabrication: UIG-75 through to UIG-84
Inspection and Tests: UIG-90 through to UIG-112
Marking and Reports: UIG-115 through to UIG-121
Pressure Relief Devices: UIG-125
MANDATORY APPENDICES: 1 through to 44
NONMANDATORY APPENDICES: A through to NN
Division 2 - Alternative Rules
This division covers the mandatory requirements, specific prohibitions and nonmandatory guidance for materials, design, fabrication, inspection and testing, markings and reports, overpressure protection and certification of pressure vessels having an internal or external pressure which exceeds 15 psi (103 kPa).
The pressure vessel can be either fired or unfired. The pressure may be from external sources, or by the application of heating from an indirect or direct source as a result of a process, or any combination of the two.
The rules contained in this section can be used as an alternative to the minimum requirements specified in Division 1. Generally the Division 2 rules are more onerous than in Division 1 with respect to materials, design and nondestructive examinations but higher design stress intensity values are allowed. Division 2 has also provisions for the use of finite element analysis to determine expected stress in pressure equipment, in addition to the traditional approach of design by formula (Part 5: "Design by Analysis requirements").
Division 3 - Alternative Rules for Construction of High Pressure Vessels
This division covers the mandatory requirements, specific prohibitions and nonmandatory guidance for materials, design, fabrication, inspection and testing, markings and reports, overpressure protection and certification of pressure vessels having an internal or external pressure which exceeds 10,000 psi (70,000 kPa).
The pressure vessel can be either fired or unfired. The pressure may be from external sources, by the application of heating from an indirect or direct source, process reaction or any combination thereof.
^ abAn International Code - 2010 ASME Boiler & Pressure Vessel Code Section VIII Rules for Construction of Pressure Vessels - Division 2: Alternative Rules. ASME. July 1, 2011.
^ abAn International Code - 2010 ASME Boiler & Pressure Vessel Code Section VIII Rules for Construction of Pressure Vessels - Division 3: Alternative Rules for Construction of High Pressure Vessels. ASME. July 1, 2011.