ASTM A420/A420M-22

Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service

ABSTRACT
This specification covers wrought carbon steel and alloy steel pipe fittings of seamless and welded construction for use in pressure piping and pressure vessel service at low temperatures. Materials shall consist of forgings, bars, plates, seamless or fusion welded tubular products with filler metal added, and shall be produced by open-hearth, basic-oxygen, or electric-furnace process. Forging or forming operations shall be performed by one or a combination of two or more of the following procedures: hammering, pressing, piercing, extruding, upsetting, working, bending, fusion-welding, or machining. All welding shall be completed prior to the austenitizing heat treatment, which shall be executed in the normalized, normalized and tempered, annealed, or quenched and tempered conditions. Steel specimens shall conform to required values of chemical composition, tensile strength, yield strength, elongation, wall thickness, and Charpy V-notch impact value. All fusion-welded butt joints shall undergo radiographic examination, while hydrostatic testing of fittings is not required in this specification. Repair welding shall be permissible for parts made to dimensional standards.
SCOPE
1.1 This specification2 covers wrought carbon steel and alloy steel fittings of seamless and welded construction, covered by the latest revision of ASME B16.9, ASME B16.11, MSS SP-79, MSS SP-83, MSS SP-95, and MSS SP-97. Fittings differing from these ASME and MSS standards shall be furnished in accordance with Supplementary Requirement S58 of Specification A960/A960M. These fittings are for use in pressure piping and pressure vessel service at low temperatures.  
1.2 Optional supplementary requirements are provided for fittings where a greater degree of examination is desired. When desired, one or more of these supplementary requirements shall be specified in the order.  
1.3 This specification is expressed in both inch-pound units and in SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material shall be furnished to inch-pound units.  
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Oct-2022
• ICS: 23.040.40 - Metal fittings
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.22 - Steel Forgings and Wrought Fittings for Piping Applications and Bolting Materials for Piping and Special Purpose Applications

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:A420/A420M −22
Standard Specification for
Piping Fittings of Wrought Carbon Steel and Alloy Steel for
1
Low-Temperature Service
This standard is issued under the fixed designationA420/A420M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* 2. Referenced Documents
2
2.1 In addition to those Referenced Documents listed in
1.1 This specification covers wrought carbon steel and
Specification A960/A960M, the following list of standards
alloy steel fittings of seamless and welded construction, cov-
apply to this specification.
ered by the latest revision of ASME B16.9, ASME B16.11,
3
MSS SP-79, MSS SP-83, MSS SP-95, and MSS SP-97.
2.2 ASTM Standards:
Fittings differing from these ASME and MSS standards shall
A350/A350M SpecificationforCarbonandLow-AlloySteel
be furnished in accordance with Supplementary Requirement
Forgings, Requiring Notch Toughness Testing for Piping
S58ofSpecificationA960/A960M.Thesefittingsareforusein
Components
pressure piping and pressure vessel service at low tempera-
A370 Test Methods and Definitions for Mechanical Testing
tures.
of Steel Products
A960/A960M Specification for Common Requirements for
1.2 Optional supplementary requirements are provided for
Wrought Steel Piping Fittings
fittings where a greater degree of examination is desired.When
A1058 Test Methods for Mechanical Testing of Steel
desired,oneormoreofthesesupplementaryrequirementsshall
Products—Metric
be specified in the order.
2.3 ASME Standards:
1.3 This specification is expressed in both inch-pound units
4
B16.9 Factory-Made Wrought Steel Butt-Welding Fittings
and in SI units. However, unless the order specifies the
4
B16.11 Forged Steel Fittings, Socket-Welding Threaded
applicable “M” specification designation (SI units), the mate-
4
2.4 ASME Boiler and Pressure Vessel Code:
rial shall be furnished to inch-pound units.
Section III
1.4 The values stated in either SI units or inch-pound units
4
Section VIII Division 1, Pressure Vessels
are to be regarded separately as standard. Within the text, the
Section IX
SI units are shown in brackets. The values stated in each
2.5 MSS Standards:
system may not be exact equivalents; therefore, each system
MSS SP-25 Standard Marking System for Valves, Fittings,
shall be used independently of the other. Combining values
5
Flanges, and Unions
from the two systems may result in non-conformance with the
5
MSS SP-79 Socket Welding Reducer Inserts
standard.
MSS SP-83 Steel Pipe Unions, Socket-Welding and
1.5 This international standard was developed in accor- 5
Threaded
5
dance with internationally recognized principles on standard-
MSS SP-95 Swage(d) Nipples and Bull Plugs
ization established in the Decision on Principles for the
MSS SP-97 Integrally Reinforced Forged Branch Outlet
Development of International Standards, Guides and Recom-
Fittings—Socket Welding, Threaded and Buttwelding
mendations issued by the World Trade Organization Technical
Ends
Barriers to Trade (TBT) Committee.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
1
This specification is under the jurisdiction ofASTM Committee A01 on Steel, contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee Standards volume information, refer to the standard’s Document Summary page on
A01.22 on Steel Forgings and Wrought Fittings for PipingApplications and Bolting the ASTM website.
4
Materials for Piping and Special Purpose Applications. Available from American Society of Mechanical Engineers (ASME), ASME
Current edition approved Nov. 1, 2022. Published December 2022. Originally International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
approved in 1958. Last previous edition approved in 2020 as A420/A420M – 20. www.asme.org.
5
DOI: 10.1520/A0420_A0420M-22. AvailablefromManufacturersStandardizationSocietyoftheValveandFittings
2
For ASME Boiler and Pressure Vessel Code applications see related Specifi- Industry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http://www.mss-
cation SA-420 in Section II of that Code. hq.com.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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A420/A420M−22
TABLE 1 Chemical Requirements
NOTE 1—All requireme
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: A420/A420M − 20 A420/A420M − 22
Standard Specification for
Piping Fittings of Wrought Carbon Steel and Alloy Steel for
1
Low-Temperature Service
This standard is issued under the fixed designation A420/A420M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
2
1.1 This specification covers wrought carbon steel and alloy steel fittings of seamless and welded construction, covered by the
latest revision of ASME B16.9, ASME B16.11, MSS SP-79, MSS SP-83, MSS SP-95, and MSS SP-97. Fittings differing from
these ASME and MSS standards shall be furnished in accordance with Supplementary Requirement S58 of Specification
A960/A960M. These fittings are for use in pressure piping and pressure vessel service at low temperatures.
1.2 Optional supplementary requirements are provided for fittings where a greater degree of examination is desired. When desired,
one or more of these supplementary requirements shall be specified in the order.
1.3 This specification is expressed in both inch-pound units and in SI units. However, unless the order specifies the applicable “M”
specification designation (SI units), the material shall be furnished to inch-pound units.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units
are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used
independently of the other. Combining values from the two systems may result in non-conformance with the standard.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 In addition to those Referenced Documents listed in Specification A960/A960M, the following list of standards apply to this
specification.
3
2.2 ASTM Standards:
A350/A350M Specification for Carbon and Low-Alloy Steel Forgings, Requiring Notch Toughness Testing for Piping
Components
A370 Test Methods and Definitions for Mechanical Testing of Steel Products
A960/A960M Specification for Common Requirements for Wrought Steel Piping Fittings
1
This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.22
on Steel Forgings and Wrought Fittings for Piping Applications and Bolting Materials for Piping and Special Purpose Applications.
Current edition approved March 1, 2020Nov. 1, 2022. Published March 2020December 2022. Originally approved in 1958. Last previous edition approved in 20192020
as A420/A420M – 19a.A420/A420M – 20. DOI: 10.1520/A0420_A0420M-20.10.1520/A0420_A0420M-22.
2
For ASME Boiler and Pressure Vessel Code applications see related Specification SA-420 in Section II of that Code.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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A420/A420M − 22
TABLE 1 Chemical Requirements
NOTE 1—All requirements are maximum unless otherwise indicated.
NOTE 2—Where an ellipsis (.) appears in this table, there is no requirement.
A
Grade Composition, %
E
C Mn P S Si Ni Cr Mo Cu Nb V
B
WPL6 0.30 0.50–1.35 0.035 0.040 0.15–0.40 0.40 0.30 0.12 0.40 0.02 0.08
WPL9 0.20 0.40–1.06 0.030 0.030 . . . 1.60–2.24 0.75–1.25
C
WPL3 0.20 0.31–0.64 0.05 0.05 0.13–0.37 3.2–3.8 . . .
D
WPL8 0.13 0.90 0.030 0.030 0.13–0.37 8.4–9.6 . . .
A
When fittings are of welded construction, the symbols above shall be supplemented by the letter “W”.
B
By agreement, the limit for niobium may be increased up to 0.05 % on heat analysis and 0.06 % on product analysis.
C
Fittings made from plate or forgings may have 0.90 % max manganese.
D
Fittings made from plate may have 0.98 % max
...