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The American National Standards Institute

The American National Standards Institute

The American National Standards Institute (ANSI) was earlier known as the American Standards Association (ASA). For a short period of time, from 1967 to 1969, it was called the United States of America Standards Institute (USASI). ANSI provides a forum for development or obtaining a consensus for approval of standards having national impact and serves as a focal point for distribution of national and other standards, including those developed and issued by the International Organization for Standardization (ISO) and foreign governments. Development and approval functions are performed by committees representing a cross section of affected interests, such as engineering societies, manufacturers, trade institutes, fabricators, builders, universities, unions, insurance companies, and government agencies. Many of the committees are chaired or sponsored by engineering societies, such as ASME and the Institute of Electrical and Electronics Engineers (IEEE). Safety is the basic objective of the engineering design and construction requirements contained in standards developed, approved, and distributed by ANSI. The ANSI standards include prohibition for practices considered unsafe and cautions where advisory warnings, instead of prohibitions, are deemed necessary. This chapter provides a brief discussion of various sections of ASME B31, Pressure Piping Code, which was earlier known as ANSI B31, Pressure Piping Code. It is envisioned that other ANSI standards may eventually become known as ASME standards; however, they shall be subjected to approval of the ANSI. The following ANSI standards contain provisions related to piping.

ANSI Standards

  • A13.1-96 --> Scheme for the Identification of Piping Systems

  • A112.1.2-91 --> Air Gaps in Plumbing Systems

  • A112.6.1M-88 --> Supports for Off-the-Floor Plumbing Fixtures for Public Use

  • A112.18.1M-96 --> Plumbing Fixture Fittings

  • A112.19.IM-94 --> Enameled Cast Iron Plumbing Fixtures

  • A112.19.3M-87 --> Stainless Steel Plumbing Fixtures (de- signed for residential use) (R1996)

  • A112.21.1M-91 --> Floor Drains

  • A112.21.2M-83 --> Roof Drains (revision of ANSI A112.21.2-1971)

  • A112.36.2M-91 --> Cleanouts (revision of ANSI A112.36.2-1983)

  • AG-1-94 --> Code on Nuclear Air and Gas Treatment

  • B1.1 --> Unified Inch Screw Threads

  • B1.20.1-83 --> Pipe Threads General Purpose (Inch) (revision and redesignation of ASME/ANSI B2.1-1968) (R1992)

  • B1.20.3-76 --> Dryseal Pipe Threads (Inch) (revision and redesignation of B2.2-1968) (R1991)

  • B16.1-89 --> Cast Iron Pipe Flanges and Flanged Fit- tings

  • B16.3-92 --> Malleable Iron Threaded Fittings; Classes 150 and 300

  • B16.4.92 --> Cast Iron Threaded Fittings; Classes 125 and 250

  • B16.5-96 --> Pipe Flanges and Flanged Fittings

  • B16.9-93 --> Factory-Made Wrought Steel Butt- Welding Fittings

  • B16.10-92 --> Face-To-Face and End-To-End Dimen- sions of Valves

  • B16.11-96 --> Forged Steel Fittings, Socket-Welding and Threaded

  • B16.12-91 --> Cast Iron Threaded Drainage Fittings

  • B16.14-91 --> Ferrous Pipe Plugs, Bushings, and Lock- nuts with Pipe Threads

  • B16.15-85 --> Cast Bronze Threaded Fittings; Classes 125 and 250

  • B16.18-84 --> Cast Copper Alloy Solder Joint Pressure Fittings (R1994)

  • B16.22-95 --> Wrought Copper and Copper Alloy Sol- der Joint Pressure Fittings

  • B16.23-92 --> Cast Copper Alloy Solder Joint Drain- age Fittings

  • B16.24-91 --> Bronze Pipe Flanges and Flanged Fit- tings; Classes 150 and 300

  • B16.25-97 --> Butt-Welding Ends

  • B16.26-88 --> Cast Copper Alloy Fittings for Flared Copper Tubes

  • B16.28-94 --> Wrought Steel Butt-Welding Short Ra- dius Elbows and Returns

  • B16.29-94 --> Wrought Copper and Wrought Copper Alloy Solder Joint Drainage Fittings

  • B16.32-92 --> Cast Copper Alloy Solder Joint Fittings for Solvent Drainage Systems

  • B16.33-90 --> Manually Operated Metallic Gas Valves for Use in Gas Piping Systems up to 125 psig (sizes ¹⁄₂ through 2)

  • B16.34-96 --> Valves—Flanged, Threaded, and Weld- ing End

  • B16.36-96 --> Orifice Flanges

  • B16.38-85 --> Large Metallic Valves for Gas Distribu- tion (manually operated, NPS 2 ¹⁄₂ to 12, 125 psig maximum) (R1994)

  • B16.39-86 --> Malleable Iron Threaded Pipe Unions; Classes 150, 250, and 300 (R1994)

  • B16.40-85 --> Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribu- tion Systems (R1994)

  • B16.41-83 --> Functional Qualification Requirements for Power-Operated Active Valve As- semblies for Nuclear Power Plants (R1989)

  • B16.42-87 --> Ductile Iron Pipe Flanges and Flanged Fittings; Classes 150 and 300 (R1997)

  • B16.44-95 --> Manually Operated Metallic Gas Valves for Use in House Piping Systems

  • B16.45-87 --> Cast Iron Fittings for Sovent Drainage Systems

  • B16.47-96 --> Large Diameter Steel Flanges NPS 26 through NPS 60

  • B18.2.1-96 --> Square and Hex Bolts and Screws (Inch Series) Including Hex Cap Screws and Lag Screws; Supplement 1318.2.1

  • B18.2.2-87 --> Square and Hex Nuts (Inch Series)

  • B18.2.3.1M-79 --> Metric Hex Cap Screws (R1995)

  • B18.2.3.2M-79 --> Metric Formed Hex Screws (R1995)

  • B18.2.3.3M-79 --> Metric Heavy Hex Screws (R1995)

  • B18.2.3.4M-84 --> Metric Hex Flange Screws (R1995)

  • B18.2.3.5M-79 --> Metric Hex Bolts; Errata-May 1981 (R1995)

  • B18.2.3.6M-79 --> Metric Heavy Hex Bolts (R1995)

  • B18.2.4.1M-79 --> Metric Hex Nuts, Style 1 (R1995)

  • B18.2.4.2M-79 --> Metric Hex Nuts, Style 2 (R1995)

  • B18.2.4.3M-79 --> Metric Slotted Hex Nuts (R1995)

  • B18.2.4.4M-82 --> Metric Hex Flange Nuts (R1993)

  • B18.2.4.5M-79 --> Metric Hex Jam Nuts (R1990)

  • B18.2.4.6M-79 --> Metric Heavy Hex Nuts (R1990)

  • B18.5-90 --> Round Head Bolts (Inch Series)

  • B18.5.2.1M-81 --> Metric Round Head Short Square Neck Bolts (R1995)

  • B18.5.2.2M-82 --> Metric Round Head Square Neck Bolts (R1993)

  • B18.15-85 --> Forged Eyebolts (R1995)

  • B18.18.1M-87 --> Inspection and Quality Assurance for General Purpose Fasteners (R1994)

  • B18.18.3M-87 --> Inspection and Quality Assurance for Special Purpose Fasteners (R1993)

  • B18.18.4M-87 --> Inspection and Quality Assurance for Fasteners for Highly Specialized Engi- neered Applications (R1993)

  • B18.21.1-72 --> Lock Washers (Inch Series)

  • B18.21.2M-94 --> Lock Washers (Metric Series)

  • B18.22M-81 --> Metric Plain Washers (R1990)

  • B18.22.1-65 --> Plain Washers (reaffirmation and re-designation of ASA 1327.2-1965) (R1990)

  • B32.5-77 --> Preferred Metric Sizes for Tubular Metal Products Other than Pipe (R1988)

  • B32.6M-84 --> Preferred Metric Equivalents of Inch Sizes for Tubular Products Other than Pipe (revision of ANSI B32.6-1977) (R1994)

  • B36.10M-96 --> Welded and Seamless Wrought Steel Pipe (revision of ANSI B36.10)

  • B36.19M-85 --> Stainless Steel Pipe (revision of ANSI B36.19)

  • MFC-1M-91 --> Glossary of Terms Used in the Measure- ment of Fluid Flow in Pipes

  • MFC-6M-87 --> Measurement of Fluid Flow in Pipes Using Vortex Flow Meters

  • MFC-7M-87 --> Measurement of Gas Flow by Means of Critical Flow Venturi Nozzles (R1992)

  • N45.2.1-80 --> Cleaning of Fluid Systems and Associ- ated Components for Nuclear Power Plants

  • N278.1-75 --> Self-Operated and Power-Operated Safety-Related Valves Functional Specification Standard, Reactor Plants and Their Maintenance (R 1992)

  • NQA-1-1997 --> Quality Assurance Program Require- ments for Nuclear Facilities

  • TDP-1-85 --> Recommended Practices for the Preven- tion of Water Damage to Steam Tur- bines Used for Electric Power Gener- ation (Fossil)

  • TDP-2-85 --> Recommended Practices for the Prevention of Water Damage to Steam Turbines Used for Electric Power Generation (Revision of ASME Standard No. TWDPS-1-1973, Part 2) (Nuclear)

ANSI Guides/Manuals

  • 1986 --> Guide for Gas Transmission and Distribution Piping Systems-1986; Addenda 1-1986, Addenda 2-1987, Addenda 3-1987

  • B31 Guide-77 --> Corrosion Control for ANSI B31.1, Power Piping Systems

  • B31 Guide-91 --> Manual for Determining the Remaining Strength of Corroded Pipelines (a supplement to ASME B31 Code for Pressure Piping)

  • 1001-88 --> Performance Requirements for Pipe Applied Atmospheric Type Vacuum Breakers

  • 1003-93 --> Performance Requirements for Water Pressure Reducing Valves

  • 1037-90 --> Performance Requirements for Pressur- ized Flushing Devices (Flushometers) for Plumbing Fixtures

  • 1045-87 --> Performance Standard and Installation Procedures for Aluminum Drain, Waste, and Vent Pipe with End Cap Components.


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