ASTM A961/A961M-14

Standard Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping Applications<?Pub _bookmark Command="[Quick Mark]"?>

ABSTRACT
This specification covers a group of common requirements that shall apply to steel flanges, forged fittings, valves, and parts for piping applications. If the primary melting is required it shall incorporate separate degassing or refining and may be followed by secondary melting, such as electroslag remelting or vacuum remelting. If secondary melting is employed, the heat shall be defined as all of the ingot remelted from a single primary heat. Material requiring heat treatment shall be treated as specified in the individual product specification using the following procedures such as full annealing, solution annealing, isothermal annealing, normalizing, tempering and post-weld heat treatment, stress relieving. Heat analysis shall be used to determine the percentages of carbon, manganese, phosphorus, sulfur, silicon, chromium, nickel, molybdenum, titanium, tantalum, copper, cobalt, nitrogen, aluminum, vanadium, cerium to meet the required chemical composition. The product analysis shall be used to determine if the chemical composition shall conform to the limits of the product specified. Mechanical tests shall be performed to determine the mechanical properties such as hardness, tensile properties, and impact properties.
SCOPE
1.1 This specification covers a group of common requirements that shall apply to steel flanges, forged fittings, valves, and parts for piping applications under any of the following individual product specifications:    
Title of Specification  
ASTM Designation  
Forgings, Carbon Steel, for Piping Components  
A105/A105M  
Forgings, Carbon Steel, for General-Purpose Piping  
A181/A181M  
Forged or Rolled Alloy-Steel Pipe Flanges, Forged  
A182/A182M  
Fittings, and Valves and Parts for High Temperature
Service  
Forgings, Carbon and Low Alloy Steel, Requiring Notch  
A350/A350M  
Toughness Testing for Piping Components  
Forged or Rolled 8 and 9 % Nickel Alloy  
A522/A522M  
Steel Flanges, Fittings, Valves, and Parts  
for Low-Temperature Service  
Forgings, Carbon and Alloy Steel, for Pipe Flanges,  
A694/A694M  
Fittings, Valves, and Parts for High-Pressure
Transmission Service  
Flanges, Forged, Carbon and Alloy Steel for Low  
A707/A707M  
Temperature Service  
Forgings, Carbon Steel, for Piping Components with  
A727/A727M  
Inherent Notch Toughness  
Forgings, Titanium-Stabilized Carbon Steel, for  
A836/A836M  
Glass-Lined Piping and Pressure Vessel Service  
1.2 In case of conflict between a requirement of the individual product specification and a requirement of this general requirement specification, the requirements of the individual product specification shall prevail over those of this specification.  
1.3 By mutual agreement between the purchaser and the supplier, additional requirements may be specified (see Section 4.1.2). The acceptance of any such additional requirements shall be dependent on negotiations with the supplier and must be included in the order as agreed upon between the purchaser and supplier.  
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text and the tables, 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. The inch-pound units shall apply, unless the “M” designation (SI) of the product specification is specified in the order.

General Information

• Status: Historical
• Publication Date: 31-Oct-2014
• ICS: 23.040.01 - Pipeline components and pipelines in general
• ICS: 77.140.20 - Stainless steels
• 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

Relations

• Replaces: ASTM A961/A961M-13 - Standard Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping Applications<?Pub _bookmark Command="[Quick Mark]"?>
• Effective Date: 01-Nov-2014
• Replaced By: ASTM A961/A961M-15 - Standard Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping Applications<?Pub _bookmark Command="[Quick Mark]"?>
• Effective Date: 01-Nov-2015
• Referred By: ASTM A1099/A1099M-20 - Standard Specification for Modified Alloy Steel Forgings, Forged Bar, and Rolled Bar Commonly Used in Oil and Gas Pressure Vessels
• Effective Date: 01-Nov-2014
• Referred By: ASTM A181/A181M-23 - Standard Specification for Carbon Steel Forgings, for General-Purpose Piping
• Effective Date: 01-Nov-2014
• Referred By: ASTM A522/A522M-22 - Standard Specification for Forged or Rolled 8 and 9% Nickel Alloy Steel Flanges, Fittings, Valves, and Parts for Low-Temperature Service
• Effective Date: 01-Nov-2014
• Referred By: ASTM A988/A988M-23 - Standard Specification for Hot Isostatically-Pressed Stainless Steel Flanges, Fittings, Valves, and Parts for High Temperature Service
• Effective Date: 01-Nov-2014
• Referred By: ASTM A105/A105M-23 - Standard Specification for Carbon Steel Forgings for Piping Applications
• Effective Date: 01-Nov-2014
• Referred By: ASTM A989/A989M-23 - Standard Specification for Hot Isostatically-Pressed Alloy Steel Flanges, Fittings, Valves, and Parts for High Temperature Service
• Effective Date: 01-Nov-2014
• Referred By: ASTM A707/A707M-19 - Standard Specification for Forged Carbon and Alloy Steel Flanges for Low-Temperature Service
• Effective Date: 01-Nov-2014
• Referred By: ASTM A836/A836M-14(2020) - Standard Specification for Titanium-Stabilized Carbon Steel Forgings for Glass-Lined Piping and Pressure Vessel Service
• Effective Date: 01-Nov-2014
• Referred By: ASTM A727/A727M-14(2019) - Standard Specification for Carbon Steel Forgings for Piping Components with Inherent Notch Toughness
• Effective Date: 01-Nov-2014
• Referred By: ASTM A182/A182M-23 - Standard Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature Service
• Effective Date: 01-Nov-2014
• Referred By: ASTM A694/A694M-16(2022) - Standard Specification for Carbon and Alloy Steel Forgings for Pipe Flanges, Fittings, Valves, and Parts for High-Pressure Transmission Service
• Effective Date: 01-Nov-2014
• Referred By: ASTM A350/A350M-23 - Standard Specification for Carbon and Low-Alloy Steel Forgings, Requiring Notch Toughness Testing for Piping Components
• Effective Date: 01-Nov-2014

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:A961/A961M −14
StandardSpecification for
Common Requirements for Steel Flanges, Forged Fittings,
Valves, and Parts for Piping Applications
This standard is issued under the fixed designationA961/A961M; 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* the tables, the SI units are shown in brackets.The values stated
in each system may not be exact equivalents; therefore, each
1.1 This specification covers a group of common require-
system shall be used independently of the other. Combining
ments that shall apply to steel flanges, forged fittings, valves,
values from the two systems may result in non-conformance
and parts for piping applications under any of the following
with the standard. The inch-pound units shall apply, unless the
individual product specifications:
“M”designation(SI)oftheproductspecificationisspecifiedin
Title of Specification ASTM Designation
the order.
Forgings, Carbon Steel, for Piping Components A105/A105M
Forgings, Carbon Steel, for General-Purpose Piping A181/A181M 2. Referenced Documents
Forged or Rolled Alloy-Steel Pipe Flanges, Forged A182/A182M
2.1 ASTM Standards:
Fittings, and Valves and Parts for High Temperature
Service
A105/A105M Specification for Carbon Steel Forgings for
Forgings, Carbon and Low Alloy Steel, Requiring Notch A350/A350M
Piping Applications
Toughness Testing for Piping Components
A181/A181M Specification for Carbon Steel Forgings, for
Forged or Rolled 8 and 9 % Nickel Alloy A522/A522M
Steel Flanges, Fittings, Valves, and Parts
General-Purpose Piping
for Low-Temperature Service
A182/A182M Specification for Forged or Rolled Alloy and
Forgings, Carbon and Alloy Steel, for Pipe Flanges, A694/A694M
Stainless Steel Pipe Flanges, Forged Fittings, and Valves
Fittings, Valves, and Parts for High-Pressure
Transmission Service
and Parts for High-Temperature Service
Flanges, Forged, Carbon and Alloy Steel for Low A707/A707M
A275/A275M Practice for Magnetic Particle Examination of
Temperature Service
Steel Forgings
Forgings, Carbon Steel, for Piping Components with A727/A727M
Inherent Notch Toughness
A350/A350M SpecificationforCarbonandLow-AlloySteel
Forgings, Titanium-Stabilized Carbon Steel, for A836/A836M
Forgings, Requiring Notch Toughness Testing for Piping
Glass-Lined Piping and Pressure Vessel Service
Components
1.2 In case of conflict between a requirement of the indi-
A370 Test Methods and Definitions for Mechanical Testing
vidual product specification and a requirement of this general
of Steel Products
requirement specification, the requirements of the individual
A522/A522M Specification for Forged or Rolled 8 and 9%
product specification shall prevail over those of this specifica-
NickelAlloy Steel Flanges, Fittings, Valves, and Parts for
tion.
Low-Temperature Service
1.3 By mutual agreement between the purchaser and the
A694/A694M Specification for Carbon and Alloy Steel
supplier, additional requirements may be specified (see Section
Forgings for Pipe Flanges, Fittings, Valves, and Parts for
4.1.2). The acceptance of any such additional requirements
High-Pressure Transmission Service
shall be dependent on negotiations with the supplier and must
A700 Guide for Packaging, Marking, and Loading Methods
be included in the order as agreed upon between the purchaser
for Steel Products for Shipment
and supplier.
A707/A707M Specification for Forged Carbon and Alloy
Steel Flanges for Low-Temperature Service
1.4 The values stated in either SI units or inch-pound units
A727/A727M Specification for Carbon Steel Forgings for
are to be regarded separately as standard. Within the text and
Piping Components with Inherent Notch Toughness
A751 Test Methods, Practices, and Terminology for Chemi-
cal Analysis of Steel Products
This specification is under the jurisdiction ofASTM Committee A01 on Steel,
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee
A01.22 on Steel Forgings andWrought Fittings for PipingApplications and Bolting
Materials for Piping and Special Purpose Applications. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Nov. 1, 2014. Published November 2014. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1996. Last previous edition approved in 2013 as A961/A961M–13. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/A0961_A0961M-14. 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
A961/A961M−14
A836/A836M Specification for Titanium-Stabilized Carbon 3.2.6 seamless tubing, n—a tubular product made without a
Steel Forgings for Glass-Lined Piping and PressureVessel welded seam.
Service 3.2.6.1 Discussion—Itismanufacturedusuallybyhotwork-
A941 TerminologyRelatingtoSteel,StainlessSteel,Related ing the material, and if necessary, by subsequently cold
Alloys, and Ferroalloys finishing the hot worked tubular product to produce the desired
A967 Specification for Chemical Passivation Treatments for shape, dimensions and properties.
Stainless Steel Parts
4. Ordering Information
A991/A991M Test Method for Conducting Temperature
Uniformity Surveys of Furnaces Used to Heat Treat Steel
4.1 It is the purchaser’s responsibility to specify in the
Products
purchase order all ordering information necessary to purchase
A1058 Test Methods for Mechanical Testing of Steel
theneededmaterial.Examplesofsuchinformationinclude,but
Products—Metric
are not limited to, the following:
B880 Specification for General Requirements for Chemical
4.1.1 Quantity,
Check Analysis Limits for Nickel, Nickel Alloys and
4.1.2 Size and pressure class or dimensions, (tolerances and
Cobalt Alloys
surface finishes should be included),
E165 Practice for Liquid Penetrant Examination for General
4.1.3 Specification number with grade or class, or both, as
Industry
applicable, and year/date,
E381 Method of Macroetch Testing Steel Bars, Billets,
4.1.4 Choice of testing track from the options listed in Test
Blooms, and Forgings
Methods A1058 when material is ordered to an M suffix (SI
E709 Guide for Magnetic Particle Testing
units) product standard. If the choice of test track is not
E1916 Guide for Identification of Mixed Lots of Metals
specified in the order, then the default ASTM track shall be
2.2 ASME Standard: used as noted in Test Methods A1058,
4.1.5 Supplementary requirements, and
ASME Boiler and Pressure Vessel Code–Section IX
4.1.6 Additional requirements.
2.3 Manufacturer’s Standardization Society Standard:
SP 25 StandardMarkingSystemofValves,Fittings,Flanges
5. Melting Process
and Unions
5.1 Unless otherwise specified in the individual Product
3. Terminology
Specification, the steel shall be fully killed.
3.1 Definitions—For definitions of other terms used in this 5.2 If a specific type of melting is required by the purchaser,
specification, refer to Terminology A941. it shall be stated on the purchase order.
3.2 Definitions of Terms Specific to This Standard: 5.3 The primary melting may incorporate separate degas-
3.2.1 bar, n—a solid rolled or forged section that is long in sing or refining and may be followed by secondary melting,
relationship to its cross sectional dimensions, with a relatively such as electroslag remelting or vacuum remelting. If second-
constant cross section throughout its length and a wrought ary melting is employed, the heat shall be defined as all of the
microstructure. ingot remelted from a single primary heat.
3.2.2 certifying organization, n—the company or associa-
5.4 Steel may be cast in ingots or may be strand cast. When
tion responsible for the conformance of, the marking of, and
steel of different grades is sequentially strand cast, identifica-
the certification of the product to the specification require-
tion of the resultant transition material is required. The steel
ments.
producer shall remove the transition material by an established
procedure that positively separates the grades.
3.2.3 fitting, n—a component for non-bolted joints in piping
systems.
5.5 A sufficient discard shall be made from the source
material to secure freedom from injurious porosity and
3.2.4 flange, n—a component for bolted joints used in
piping systems. shrinkage, and undue segregation.
3.2.5 forging, n—the product of a substantially compressive
6. Manufacture
hot or cold plastic working operation that consolidates the
6.1 The finished part shall be manufactured from a forging
material and produces the required shape.
that is as close as practicable to the finished size or shape.
3.2.5.1 Discussion—Theplasticworkingmustbeperformed
Alternative starting materials may be used, but with the
by a forging machine, such as a hammer, press, or ring rolling
following exceptions and requirements.
machine, and must deform the material to produce a wrought
6.1.1 Bar—Flanges, elbows, return bends, tees, and header
structure throughout the material cross section.
tees shall not be machined directly from bar. Other hollow
cylindrical shaped parts up to, and including, NPS 4 can be
machined from bar provided that the axial length of the part is
Available from American Society of Mechanical Engineers (ASME), ASME
International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
approximately parallel to the metal flow lines of the starting
www.asme.org.
stock.
AvailablefromManufacturersStandardizationSocietyoftheValveandFittings
6.1.2 Wrought Seamless Pipe and Tubing—Flangesshallnot
Industry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http://www.mss-
hq.com. be machined directly from seamless pipe or tubing. Other
A961/A961M−14
hollow cylindrical shaped parts can be machined from seam- 8.3 Product Analysis—If a product analysis is performed it
less pipe and tubing provided that the axial length of the part shall be in accordance with Test Methods, Practices, and
is approximately parallel to the metal flow lines of the starting Terminology A751. Samples for analysis shall be taken from
stock. midway between center and surface of solid parts, midway
between inner and outer surfaces of hollow parts, midway
7. Heat Treatment between center and surface of full-size prolongations or from
broken mechanical test specimens. The chemical composition
7.1 Material requiring heat treatment shall be treated as
thus determined shall conform to the limits of the product
specified in the individual product specification using the
specification, within the permissible variations of Table 1 or
following procedures that are defined in more detail in Termi-
Table 2 of this specification, as appropriate for the grade being
nology A941.
supplied.
7.1.1 Full Annealing—Material shall be uniformly reheated
to a temperature above the transformation range and, after
9. Mechanical Requirements
holding for a sufficient time at this temperature, cooled slowly
9.1 Method of Mechanical Tests—All tests shall be con-
to a temperature below the transformation range.
ducted in accordance with Test Methods and Definitions A370
7.1.2 Solution Annealing—Material shall be heated to a
if the inch-pound units are specified or Test Methods A1058 if
temperature that causes the chrome carbides to go into
the M suffix (SI units) is specified.
solution, and then, quenched in water or rapidly cooled by
other means to prevent reprecipitation.
9.2 For the purpose of determining conformance to the
7.1.3 Isothermal Annealing—Isothermal annealing shall
product specification requirements, specimens shall be ob-
consist of austenitizing a ferrous alloy, and then, coolingtoand
tained from the production forgings, or from separately forged
holding within the range of temperature at which the austenite
test blanks prepared from the stock used to make the finished
transforms to a relatively soft ferrite-carbide aggregate. product. In either case, mechanical test specimens shall not be
7.1.4 Normalizing— Material shall be uniformly reheated to removed until after all heat treatment is complete. If repair
a temperature above the transformation range, and welding is performed, test specimens shall not be removed
subsequently, cooled in air at room temperature. until after post-weld heat treatment is complete, unless permit-
ted by the product specification. The locations from which test
7.1.5 Tempering and Post-Weld Heat Treatment—Material
shall be reheated to the prescribed temperature below the specimensareremovedshallbeinaccordancewiththeProduct
Specification.
transformation range, held at temperature for the greater of 30
minor1h/in.[25.4mm]ofthicknessatthethickestsectionand
9.3 If separately forged test blanks are used, they shall be of
cooled in still air.
the same heat of steel, be subjected to substantially the same
7.1.6 Stress Relieving—Material shall be uniformly heated
reduction and working as the production forging they
to the selected stress relieving temperature. The temperature
represent, be heat treated in the same furnace charge except as
shall not vary from the selected temperature by more than 625
provided for in the reduced testing provisions of the product
°F [614 °C].
specification, under the same conditions as the production
7.1.7 Quench and Temper—Material shall be fully austen-
forging, and be of the same nominal thickness as the maximum
itized and quenched immediately in a suitable liquid medium.
heat treated thickness of the production forging.
The quenched fittings shall be reheated to a minimum tempera-
9.4 When parts are machined from bar or seamless tubing,
ture of 1100 °F [590 °C] and cooled in still air.
as permitted in 6.1.1 and 6.1.2, the mechanical properties may
7.1.8 Same Heat Treat Cycle—Heat treat loads at the same
be determined for the parts from the starting material, if the
temperature, equivalent soak times as appropriate for the
parts have not been subjected to any subsequent thermal
maximum section size on the respective load and equivalent
processing since the time of mechanical test.
cooling methods.
10. Hardness Requirements
8. Chemical Requirements
10.1 The part shall conform to the hardness requirements
8.1 Chemical Analysis—Samples for chemical analysis and
prescribed in the product specification.
methods of analysis shall be in accordance with Test Methods,
10.2 Sampling for hardness testing shall conform to the
Practices, and Terminology A751.
product specification.
8.2 Heat Analysis—Ananalysisofeach
...

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: A961/A961M − 13 A961/A961M − 14
Standard Specification for
Common Requirements for Steel Flanges, Forged Fittings,
Valves, and Parts for Piping Applications
This standard is issued under the fixed designation A961/A961M; 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*
1.1 This specification covers a group of common requirements that shall apply to steel flanges, forged fittings, valves, and parts
for piping applications under any of the following individual product specifications:
Title of Specification ASTM Designation
Forgings, Carbon Steel, for Piping Components A105/A105M
Forgings, Carbon Steel, for General-Purpose Piping A181/A181M
Forged or Rolled Alloy-Steel Pipe Flanges, Forged A182/A182M
Fittings, and Valves and Parts for High Temperature
Service
Forgings, Carbon and Low Alloy Steel, Requiring Notch A350/A350M
Toughness Testing for Piping Components
Forged or Rolled 8 and 9 % Nickel Alloy A522/A522M
Steel Flanges, Fittings, Valves, and Parts
for Low-Temperature Service
Forgings, Carbon and Alloy Steel, for Pipe Flanges, A694/A694M
Fittings, Valves, and Parts for High-Pressure
Transmission Service
Flanges, Forged, Carbon and Alloy Steel for Low A707/A707M
Temperature Service
Forgings, Carbon Steel, for Piping Components with A727/A727M
Inherent Notch Toughness
Forgings, Titanium-Stabilized Carbon Steel, for A836/A836M
Glass-Lined Piping and Pressure Vessel Service
1.2 In case of conflict between a requirement of the individual product specification and a requirement of this general
requirement specification, the requirements of the individual product specification shall prevail over those of this specification.
1.3 By mutual agreement between the purchaser and the supplier, additional requirements may be specified (see Section 4.1.2).
The acceptance of any such additional requirements shall be dependent on negotiations with the supplier and must be included in
the order as agreed upon between the purchaser and supplier.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text and the
tables, 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.
The inch-pound units shall apply, unless the “M” designation (SI) of the product specification is specified in the order.
2. Referenced Documents
2.1 ASTM Standards:
A105/A105M Specification for Carbon Steel Forgings for Piping Applications
A181/A181M Specification for Carbon Steel Forgings, for General-Purpose Piping
A182/A182M Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts
for High-Temperature Service
A275/A275M Practice for Magnetic Particle Examination of Steel Forgings
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 Oct. 1, 2013Nov. 1, 2014. Published October 2013November 2014. Originally approved in 1996. Last previous edition approved in 20122013
as A961/A961M–12a.–13. DOI: 10.1520/A0961_A0961M-13.10.1520/A0961_A0961M-14.
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
A961/A961M − 14
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
A522/A522M Specification for Forged or Rolled 8 and 9% Nickel Alloy Steel Flanges, Fittings, Valves, and Parts for
Low-Temperature Service
A694/A694M Specification for Carbon and Alloy Steel Forgings for Pipe Flanges, Fittings, Valves, and Parts for High-Pressure
Transmission Service
A700 Guide for Packaging, Marking, and Loading Methods for Steel Products for Shipment
A707/A707M Specification for Forged Carbon and Alloy Steel Flanges for Low-Temperature Service
A727/A727M Specification for Carbon Steel Forgings for Piping Components with Inherent Notch Toughness
A751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products
A836/A836M Specification for Titanium-Stabilized Carbon Steel Forgings for Glass-Lined Piping and Pressure Vessel Service
A941 Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
A967 Specification for Chemical Passivation Treatments for Stainless Steel Parts
A991/A991M Test Method for Conducting Temperature Uniformity Surveys of Furnaces Used to Heat Treat Steel Products
A1058 Test Methods for Mechanical Testing of Steel Products—Metric
B880 Specification for General Requirements for Chemical Check Analysis Limits for Nickel, Nickel Alloys and Cobalt Alloys
E165 Practice for Liquid Penetrant Examination for General Industry
E381 Method of Macroetch Testing Steel Bars, Billets, Blooms, and Forgings
E709 Guide for Magnetic Particle Testing
E1916 Guide for Identification of Mixed Lots of Metals
2.2 ASME Standard:
ASME Boiler and Pressure Vessel Code–Section IX
2.3 Manufacturer’s Standardization Society Standard:
SP 25 Standard Marking System of Valves, Fittings, Flanges and Unions
3. Terminology
3.1 Definitions—For definitions of other terms used in this specification, refer to Terminology A941.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 bar, n—a solid rolled or forged section that is long in relationship to its cross sectional dimensions, with a relatively
constant cross section throughout its length and a wrought microstructure.
3.2.2 certifying organization, n—the company or association responsible for the conformance of, the marking of, and the
certification of the product to the specification requirements.
3.2.3 fitting, n—a component for non-bolted joints in piping systems.
3.2.4 flange, n—a component for bolted joints used in piping systems.
3.2.5 forging, n—the product of a substantially compressive hot or cold plastic working operation that consolidates the material
and produces the required shape.
Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, ThreeTwo Park Ave., New York, NY 10016-5990,
http://www.asme.org.
Available from Manufacturers Standardization Society of the Valve and Fittings Industry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http://www.mss-hq.com.
3.2.5.1 Discussion—
The plastic working must be performed by a forging machine, such as a hammer, press, or ring rolling machine, and must deform
the material to produce a wrought structure throughout the material cross section.
3.2.6 seamless tubing, n—a tubular product made without a welded seam.
3.2.6.1 Discussion—
It is manufactured usually by hot working the material, and if necessary, by subsequently cold finishing the hot worked tubular
product to produce the desired shape, dimensions and properties.
4. Ordering Information
4.1 It is the purchaser’s responsibility to specify in the purchase order all ordering information necessary to purchase the needed
material. Examples of such information include, but are not limited to, the following:
A961/A961M − 14
4.1.1 Quantity,
4.1.2 Size and pressure class or dimensions, (tolerances and surface finishes should be included),
4.1.3 Specification number with grade or class, or both, as applicable, and year/date,
4.1.4 Choice of testing track from the options listed in Test Methods A1058 when material is ordered to an M suffix (SI units)
product standard. If the choice of test track is not specified in the order, then the default ASTM track shall be used as noted in Test
Methods A1058,
4.1.5 Supplementary requirements, and
4.1.6 Additional requirements.
5. Melting Process
5.1 Unless otherwise specified in the individual Product Specification, the steel shall be fully killed.
5.2 If a specific type of melting is required by the purchaser, it shall be stated on the purchase order.
5.3 The primary melting may incorporate separate degassing or refining and may be followed by secondary melting, such as
electroslag remelting or vacuum remelting. If secondary melting is employed, the heat shall be defined as all of the ingot remelted
from a single primary heat.
5.4 Steel may be cast in ingots or may be strand cast. When steel of different grades is sequentially strand cast, identification
of the resultant transition material is required. The steel producer shall remove the transition material by an established procedure
that positively separates the grades.
5.5 A sufficient discard shall be made from the source material to secure freedom from injurious porosity and shrinkage, and
undue segregation.
6. Manufacture
6.1 The finished part shall be manufactured from a forging that is as close as practicable to the finished size or shape. Alternative
starting materials may be used, but with the following exceptions and requirements.
6.1.1 Bar—Flanges, elbows, return bends, tees, and header tees shall not be machined directly from bar. Other hollow
cylindrical shaped parts up to, and including, NPS 4 can be machined from bar provided that the axial length of the part is
approximately parallel to the metal flow lines of the starting stock.
6.1.2 Wrought Seamless Pipe and Tubing—Flanges shall not be machined directly from seamless pipe or tubing. Other hollow
cylindrical shaped parts can be machined from seamless pipe and tubing provided that the axial length of the part is approximately
parallel to the metal flow lines of the starting stock.
7. Heat Treatment
7.1 Material requiring heat treatment shall be treated as specified in the individual product specification using the following
procedures that are defined in more detail in Terminology A941.
7.1.1 Full Annealing—Material shall be uniformly reheated to a temperature above the transformation range and, after holding
for a sufficient time at this temperature, cooled slowly to a temperature below the transformation range.
7.1.2 Solution Annealing—Material shall be heated to a temperature that causes the chrome carbides to go into solution, and
then, quenched in water or rapidly cooled by other means to prevent reprecipitation.
7.1.3 Isothermal Annealing—Isothermal annealing shall consist of austenitizing a ferrous alloy, and then, cooling to and holding
within the range of temperature at which the austenite transforms to a relatively soft ferrite-carbide aggregate.
7.1.4 Normalizing— Material shall be uniformly reheated to a temperature above the transformation range, and subsequently,
cooled in air at room temperature.
7.1.5 Tempering and Post-Weld Heat Treatment—Material shall be reheated to the prescribed temperature below the
transformation range, held at temperature for the greater of 30 min or 1 h/in. [25.4 mm] of thickness at the thickest section and
cooled in still air.
7.1.6 Stress Relieving—Material shall be uniformly heated to the selected stress relieving temperature. The temperature shall not
vary from the selected temperature by more than 625 °F [614 °C].
7.1.7 Quench and Temper—Material shall be fully austenitized and quenched immediately in a suitable liquid medium. The
quenched fittings shall be reheated to a minimum temperature of 1100 °F [590 °C] and cooled in still air.
7.1.8 Same Heat Treat Cycle—Heat treat loads at the same temperature, equivalent soak times as appropriate for the maximum
section size on the respective load and equivalent cooling methods.
8. Chemical Requirements
8.1 Chemical Analysis—Samples for chemical analysis and methods of analysis shall be in accordance with Test Methods,
Practices, and Terminology A751.
8.2 Heat Analysis—An analysis of each heat of steel shall be made by the steel manufacturer to determine the percentages of
those elements specified in the individual product specification. If secondary melting processes are employed, the heat analysis
A961/A961M − 14
shall be obtained from one remelted ingot, or the product of one remelted ingot, from each primary melt. The chemical analysis
thus determined shall conform to the requirements of the individual product specification. Note that the product analysis (check
analysis) tolerances are not to be applied to the Heat Analysis requirements.
8.3 Product Analysis—If a product analysis is performed it shall be in accordance with Test Methods, Practices, and
Terminology A751. Samples for analysis shall be taken from midway between center and surface of solid parts, midway between
inner and outer surfaces of hollow parts, midway between center and surface of full-size prolongations or from broken mechanical
test specimens. The chemical composition thus determined shall conform to the limits of the product specification, within the
permissible variations of Table 1 or Table 2 of this specification, as appropriate for the grade being supplied.
TABLE 1 Product Analysis Tolerances for Higher Alloy and
A,B
Stainless Steels
Element Limit or Maximum of Tolerance Over the
Specified Range, Wt % Maximum Limit or
Under the Minimum
Limit
Carbon to 0.010, incl. 0.002
over 0.010 to 0.030, incl. 0.005
over 0.030 to 0.20 incl. 0.01
over 0.20 to 0.80, incl. 0.02
Manganese to 1.00 incl. 0.03
over 1.00 to 3.00 incl. 0.04
over 3.00 to 6.00, incl. 0.05
over 6.00 to 10.00, incl. 0.06
Phosphorous to 0.040, incl. 0.005
over 0.040 to 0.20, incl. 0.010
Sulfur to 0.040 incl. 0.005
over 0.040 to 0.20, incl. 0.010
over 0.20 to 0.50, incl. 0.020
Silicon to 1.00, incl. 0.05
over 1.00 to 3.00 incl. 0.10
over 3.00 to 7.00, incl. 0.15
Chromium over 4.00 to 10.00 incl. 0.10
over 10.00 to 15.00 incl. 0.15
over 15.00 to 20.00 incl. 0.20
over
...