Related Resources: pressure-vessel

ASME BPVC Rules Summary and Overview

ASME Pressure Vessel Design and Engineering

ASME Section VIII - Rules for Construction of Pressure Vessels

The section of the ASME BPVC consists of 3 divisions.
Division 1: This division covers the mandatory requirements, specific prohibitions and non-mandatory 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
Materials: UW-5
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
General: UF-1
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:

General: UCS-1
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
Non-mandatory 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 Non-mandatory)

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 Non-mandatory)

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:
General: UHT-1
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
Materials: ULW-5
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

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 42.
Nonmandatory Appendices: A through to MM.

Division 2 - Alternative Rules:

Covers the mandatory requirements, specific prohibitions and non-mandatory 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:

Covers the mandatory requirements, specific prohibitions and non-mandatory 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.

The Section VIII, Division 1 presents several design procedures and methods in both the Mandatory and Nonmandatory Appendices; however, design procedures in the appendices differ from those in the body of the Code. As an example, Appendix 2 provides methods for designing multibolted flanges. Paragraph 2-1 (c) recommends that bolted flange connections, be used within the material, size, and pressure temperature ratings listed in UG-44. UCI-3 and UCD-3 also have restrictions on the pressure-temperature ratings of standard flanges.

ASME Section I and Section VIII Stamps:
The UG-44 lists the following standards as acceptable:
ASME/ANSI B16.5, Pipe Flanges and Flanged Fittings;
ASME/ANSI B16.20, Metallic Gaskets for Pipe Flanges, Ring Joints, Spiral-Wound and Jacketed;
ASME/ANSI B16.24, Cast Copper Pipe Flanges and Fittings, Classes 150 to 900, 1500 and 2500;
ASME/ANSI B16.42, Ductile Iron Pipe Flanges and Flanged Fittings, Class 150 and 300;
ASME/ANSI B16.47, Large Diameter Steel Flanges, NPS 26 Through NPS 60.