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: A960/A960M − 23

Standard Specification for

Common Requirements for Wrought Steel Piping Fittings1
This standard is issued under the fixed designation A960/A960M; 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* 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 wrought steel piping fittings covered values from the two systems may result in non-conformance
in any of the following individual product specifications or any with the specification. The inch-pound units shall apply unless
other ASTM specification that invokes this specification or the “M” designation [SI] of the product specification is
portions thereof: specified in the order.
Title of Specification ASTM 1.5 This international standard was developed in accor-
Designation dance with internationally recognized principles on standard-
Specification for Piping Fittings of Wrought A234/A234M
Carbon Steel and Alloy Steel for Moderate and
ization established in the Decision on Principles for the
High Temperature Service Development of International Standards, Guides and Recom-
Specification for Wrought Austenitic Stainless A403/A403M mendations issued by the World Trade Organization Technical
Steel Piping Fittings
Specification for Piping Fittings of Wrought Carbon A420/A420M
Barriers to Trade (TBT) Committee.
Steel and Alloy Steel for Low-Temperature Service
Specification for Wrought-Carbon Steel Butt-Welding A758/A758M 2. Referenced Documents
Piping Fittings with Improved Notch Toughness
Specification for As-Welded Wrought Austenitic A774/A774M 2.1 ASTM Standards:2
Stainless Steel Fittings for General Corrosive A29/A29M Specification for General Requirements for Steel
Service at Low and Moderate Temperatures Bars, Carbon and Alloy, Hot-Wrought
Specification for Wrought Ferritic, Ferritic/Austenitic, A815/A815M
and Martensitic Stainless Steel Piping Fittings A234/A234M Specification for Piping Fittings of Wrought
Specification for Heat-Treated Carbon Steel A858/A858M Carbon Steel and Alloy Steel for Moderate and High
Fittings for Low-Temperature and Corrosive Service
Specification for Wrought High-Strength A860/A860M
Temperature Service
Ferritic Steel Butt-Welding Fittings A262 Practices for Detecting Susceptibility to Intergranular
1.2 In case of conflict between a requirement of the indi- Attack in Austenitic Stainless Steels
vidual product specification and a requirement of this general A370 Test Methods and Definitions for Mechanical Testing
requirement specification, the requirements of the individual of Steel Products
product specification shall prevail over those of this specifica- A388/A388M Practice for Ultrasonic Examination of Steel
tion. Forgings
A403/A403M Specification for Wrought Austenitic Stainless
1.3 By mutual agreement between the purchaser and the Steel Piping Fittings
supplier, additional requirements may be specified (See 4.1.8). A420/A420M Specification for Piping Fittings of Wrought
The acceptance of any such additional requirements shall be Carbon Steel and Alloy Steel for Low-Temperature Ser-
dependent on negotiations with the supplier and must be vice
included in the order as agreed upon by the purchaser and A700 Guide for Packaging, Marking, and Loading Methods
supplier. for Steel Products for Shipment
1.4 The values stated in either SI units or inch-pound units A751 Test Methods and Practices for Chemical Analysis of
are to be regarded separately as standard. Within the text and Steel Products
the tables, the SI units are shown in brackets. The values stated A758/A758M Specification for Wrought-Carbon Steel Butt-
Welding Piping Fittings with Improved Notch Toughness
A763 Practices for Detecting Susceptibility to Intergranular
1
This specification is under the jurisdiction of ASTM Committee A01 on Steel, Attack in Ferritic Stainless Steels
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
2
Materials for Piping and Special Purpose Applications. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2023. Published May 2023. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1996. Last previous edition approved in 2020 as A960/A960M – 20. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/A0960_A0960M-23. 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
 A960/A960M − 23
A774/A774M Specification for As-Welded Wrought Auste- 3.1.2 certifying organization—the company or association
nitic Stainless Steel Fittings for General Corrosive Service responsible for the conformance of, the marking of, and the
at Low and Moderate Temperatures certification of the product to the specification requirements.
A815/A815M Specification for Wrought Ferritic, Ferritic/ 3.1.3 fitting—a component for non-bolted joints used in
Austenitic, and Martensitic Stainless Steel Piping Fittings piping systems and pressure vessels.
A858/A858M Specification for Heat-Treated Carbon Steel
3.1.4 flange—a component for bolted joints used in piping
Fittings for Low-Temperature and Corrosive Service
systems and pressure vessels.
A860/A860M Specification for Wrought High-Strength Fer-
ritic Steel Butt-Welding Fittings 3.1.5 forging—the product of a substantially compressive
A941 Terminology Relating to Steel, Stainless Steel, Related hot or cold plastic working operation that consolidates the
Alloys, and Ferroalloys material and produces the required shape.
A967/A967M Specification for Chemical Passivation Treat- 3.1.5.1 Discussion—The plastic working must be performed
ments for Stainless Steel Parts by a forging machine, such as a hammer, press, or ring rolling
A1058 Test Methods for Mechanical Testing of Steel machine and must deform the material to produce an essen-
Products—Metric tially wrought structure throughout the material cross section.
E165/E165M Practice for Liquid Penetrant Testing for Gen- 3.1.6 longitudinal axis—an axis along the lengthwise direc-
eral Industry tion of the part, bar, pipe or tubing parallel to the direction of
E213 Practice for Ultrasonic Testing of Metal Pipe and the greatest extension of the steel during rolling, extruding or
Tubing forging.
E709 Guide for Magnetic Particle Testing
E1916 Guide for Identification of Mixed Lots of Metals 3.2 Definitions—For definitions of other terms used in this
specification, refer to Terminology A941.
2.2 Manufacturer’s Standardization Society Standards:3
MSS-SP-25 The Standard Marking System of Valves, 4. Ordering Information
Fittings, Flanges and Unions
4.1 It is the purchaser’s responsibility to specify in the
MSS-SP-43 Standard Practice for Light Weight Stainless
purchase order all ordering information necessary to purchase
Steel Butt-Welding Fittings
the needed material. Examples of such information include but
MSS-SP-75 Specification for High Test Wrought Butt-
are not limited to the following:
Welding Fittings
4.1.1 Quantity,
MSS-SP-79 Socket Welding Reducer Inserts
4.1.2 Description of fitting and nominal dimensions (stan-
MSS-SP-83 Class 3000 Steel Pipe Unions, Socket Welding
dard or special),
and Threaded
4.1.3 Steel composition by grade and class designation,
MSS-SP-95 Swage(d) Nipples and Bull Plugs
4.1.4 Construction, seamless or welded (unless seamless or
MSS-SP-97 Integrally Reinforced Forged Branch Outlet
welded construction is specified by the purchaser, either may
Fittings—Socket Welding, Threaded and Buttwelding
be furnished at the option of the supplier),
Ends
4.1.5 Specification number (including the year/date of
2.3 American Society of Nondestructive Testing:4 issue),
SNT-TC-1A Recommended Practice for Nondestructive 4.1.6 Choice of testing track from the options listed in Test
Testing Personnel Qualification and Certification Methods A1058 when material is ordered to an M suffix (SI
2.4 ASME Standards:5 units) product standard. If the choice of test track is not
B16.9 Steel Butt-Welding Fittings specified in the order, then the default ASTM track shall be
B16.11 Forged Steel Fittings, Socket Welding and Threaded used as noted in Test Methods A1058.
Boiler and Pressure Vessel Code Section IX 4.1.7 Supplementary requirements, and
4.1.8 Additional requirements.
3. Terminology
3.1 Definitions of Terms Specific to This Standard: 5. Material
3.1.1 bar—a solid section that is long in relationship to its 5.1 The material for fittings shall consist of forgings, bars,
cross sectional dimensions, with a relatively constant cross plates and seamless or welded tubular products.
section throughout its length. (See Specification A29/A29M
5.2 The steel shall conform to the chemical requirements of
for definitions relating to the production of hot wrought and
the individual product specification and may be made from any
cold finished bars.)
process.
5.3 Ferritic steels shall be fully killed.
3
Available from Manufacturers Standardization Society of the Valve and Fittings
Industry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http://www.mss-
5.4 If secondary melting is employed, the heat shall be
hq.com. defined as all ingots remelted from a primary heat.
4
Available from American Society for Nondestructive Testing (ASNT), P.O. Box
28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http://www.asnt.org. 6. Manufacture
5
Available from American Society of Mechanical Engineers (ASME), ASME
International Headquarters, Two Park Ave., New York, NY 10016-5990, http:// 6.1 Forging or shaping operations may be performed by any
www.asme.org. of the methods included in the individual product specification.

2
 A960/A960M − 23
6.2 Parts up to and including NPS 4 may be machined from those elements specified in the individual product specification.
bar or seamless tubular material provided the longitudinal axis If secondary melting processes are employed, the heat analysis
of the part is parallel to the longitudinal axis of the bar or shall be obtained from one remelted ingot of each primary
tubular material. Elbows, return bends, tees and header tees melt. The chemical analysis thus determined shall conform to
shall not be machined directly from bar stock. the requirements of the individual product specification. Note
6.3 Fittings, after forming at an elevated temperature, shall that the product analysis (check analysis) tolerances are not to
be cooled to a temperature below the critical range under be applied to the heat analysis requirements.
suitable conditions to prevent injury by cooling too rapidly. 8.2.1 For steels ordered under product specifications refer-
encing this specification of general requirements, the steel shall
6.4 All classes of fittings shall have the welders, welding not contain an unspecified element, other than nitrogen for
operators, and welding procedures qualified under the provi- stainless steels, for the ordered grade to the extent that the steel
sion of Section IX of the ASME Boiler and Pressure Vessel conforms to the requirements of another grade for which that
Code except that welds from the original pipe manufacturer element is a specified element having a required minimum
made without the addition of filler metal do not require such content. For this requirement, a grade is defined as an alloy
qualification. described individually and identified by its own UNS or grade
7. Heat Treatment designation in a table of chemical requirements within any
specification listed within the scope as being covered by this
7.1 Fittings requiring heat treatment shall be treated as
specification.
specified in the individual product specification using the
following procedures: 8.3 Product Analysis—If a product analysis is performed it
7.1.1 Annealing—Fittings shall be uniformly reheated to a shall be in accordance with Test Methods, Practices, and
temperature above the transformation range and, after holding Terminology A751. The chemical composition thus determined
for a sufficient time at this temperature, cooled slowly to a shall conform to limits of the product specification, within the
temperature below the transformation range. permissible variations of Table 1 of this specification.
7.1.2 Solution Annealing (or Solution Treat or Treatment)— 8.3.1 Limits on formula calculations involving elemental
Fittings shall be heated to a temperature that causes the contents shall apply only to the heat analysis, unless agreed
carbides to go into solution and then quenched in water or upon between supplier and purchaser. Where limits on formula
rapidly cooled by other means to prevent reprecipitation. calculations involving elemental contents apply to product
7.1.3 Isothermal Annealing—Isothermal annealing shall analysis by such agreement, permissible variations in the
consist of austenitizing a ferrous alloy and then cooling to and formula calculation results beyond the limits for the heat
holding within the range of temperature at which the austenite analysis shall also be agreed upon between supplier and
transforms to a relatively soft ferrite-carbide aggregate. purchaser. Examples of such formula calculations include, but
7.1.4 Normalizing—Fittings shall be uniformly reheated to a are not limited to, the following: carbon equivalent CE = C +
temperature above the transformation range and subsequently Mn/6 + (Cr + Mo + V) / 5 + (Ni + Cu) / 15; J factor = (Mn +
cooled in air at room temperature. Si) × (P + Sn) × 104; or requirements for specific elemental
7.1.5 Tempering and Post-Weld Heat Treatment—Fittings balance or sufficiency, typically related to Ti, Nb, or Al and
shall be reheated to the prescribed temperature below the interstitials C and N, such as Nb = 5 × C minimum.
transformation range, held at temperature for the greater of 1⁄2
h or 1 h/in. [25.4 mm] of thickness at the thickest section and 9. Mechanical Requirements
cooled in still air. 9.1 Method of Mechanical Test—All tests shall be con-
7.1.6 Stress Relieving—Fittings shall be uniformly heated to ducted in accordance with Test Methods and Definitions A370
the selected stress relieving temperature, held long enough to if the inch-pound units are specified or Test Methods A1058 if
reduce stresses and then cooled at a rate that will result in the the M suffix (SI Units) standard is specified.
properties required for the material grade and minimize the
development of new residual stresses. The temperature shall 9.2 The test specimen shall represent all material from the
not vary from the selected temperature by more than 6 25 °F same heat and heat treatment load whose maximum thick-
[6 14 °C]. nesses do not exceed the thickness of the test specimen or
7.1.7 Quench and Temper—Fittings shall be fully austen- blank by more than 1⁄4 in. [6 mm].
itized and immediately quenched in a suitable liquid medium. 9.3 One tension test at room temperature shall be made in
The quenched fittings shall be reheated to a minimum tempera- accordance with 9.2 from each heat in each heat treatment load.
ture of 1100 °F [590 °C] and cooled in still air. 9.3.1 If heat treatment is performed in either a continuous or
8. Chemical Requirements batch type furnace controlled within 6 25 °F [6 14 °C] of the
required heat treatment temperature and equipped with record-
8.1 Chemical Analysis—Samples for chemical analysis and ing pyrometers so that complete records of heat treatment are
methods of analysis shall be in accordance with Test Methods, available, and if the same heat treating cycles are used on the
Practices and Terminology A751 for Chemical Analysis of material represented by the tension test, then one tension test
Steel Products. from each heat shall be required, instead of one tension test
8.2 Heat Analysis—An analysis of each heat of steel shall be from each heat in each heat treatment load in accordance with
made by the manufacturer to determine the percentages of 9.2.

3
 A960/A960M − 23
TABLE 1 Product Analysis TolerancesA 9.4 Retest—When a retest is permitted by the product
Element
Limit or Maximum of
Tolerance Over the specification, it shall be performed on twice the number of
Maximum Limit or
Specified Range, Wt %
Under the Minimum Limit
representative specimens that were originally nonconforming.
Carbon to 0.010, incl 0.002 When any retest specimen does not conform to the product
over 0.010 to 0.030, incl 0.005 specification requirements for the characteristic in question, the
over 0.030 to 0.20, icl 0.01
over 0.20 to 0.80, incl 0.02
lot represented by that specimen shall be rejected or reworked
Manganese to 1.00, incl 0.03 in accordance with Section 14.
over 1.00 to 3.00, incl 0.04 9.4.1 If the results of the tension test do not conform to the
over 3.00 to 6.00, incl 0.05
over 6.00 to 10.00, incl 0.06
requirements specified in the product specification, retests are
Phosphorous to 0.040, incl 0.005 permitted as outlined in the test methods specified herein. If the
over 0.040 to 0.20, incl 0.010 results of any tension test specimen are less than specified
Sulfur to 0.040, incl 0.005
over 0.040 to 0.20, incl 0.010 because a flaw becomes evident in the test specimen during
over 0.20 to 0.50, incl 0.020 testing, a retest shall be allowed provided that the defect is not
Silicon to 1.00, incl 0.05 attributable to ruptures, cracks, or flakes in the steel.
over 1.00 to 3.00, incl 0.10
over 3.00 to 7.00, incl 0.15 9.4.2 If the average impact energy value meets the product
Chromium 0.90 and under 0.03 specification requirements, but one energy value is below the
over 0.90 to 2.10, incl 0.05 specified minimum value for individual specimens, a retest is
over 2.10 to 4.00, incl 0.07
over 4.00 to 10.00, incl 0.10 permitted. The retest shall be conducted in accordance with the
over 10.00 to 15.00, incl 0.15 test methods specified herein.
over 15.00 to 20.00, incl 0.20
over 20.00 to 30.00, incl 0.25 9.5 For the purpose of determining conformance to the
Nickel to 1.00, incl 0.03 product specification requirements, specimens shall be ob-
over 1.00 to 5.00, incl 0.07
over 5.00 to 10.00, incl 0.10
tained from a finished product, or from production material that
over 10.00 to 20.00, incl 0.15 is in the same condition of working and heat treatment as the
over 20.00 to 30.00, incl 0.20 production material.
over 30.00 to 40.00, incl 0.25
Molybdenum to 0.20, incl 0.01
over 0.20 to 0.60, incl 0.03 10. Hardness Requirements
over 0.60 to 2.00, incl 0.05
over 2.00 to 7.00, incl 0.10
10.1 The part shall conform to the hardness requirements
Titanium to 1.15, incl 0.05 prescribed in the product specification.
Niobium (Columbium) to 0.14, incl 0.02
over 0.14 to 5.50 0.05 10.2 Sampling for hardness testing shall conform to the
Tantalum to 0.10 incl 0.02 product specification.
Copper to 0.50, incl 0.03
over 0.50 to 1.00, incl 0.05
over 1.00 to 5.00, incl 0.10
11. Tensile Requirements
Cobalt 0.05 to 0.25, incl 0.01B 11.1 The part shall conform to the tensile property require-
0.25 to 5.00, incl 0.07
Nitrogen to 0.02, incl 0.005 ments prescribed in the product specification.
over 0.02 to 0.19, incl 0.01
over 0.19 to 0.25 0.02
11.2 Sampling for tensile testing shall conform to the
over 0.25 to 0.35 0.03 product specification.
over 0.35 to 0.45 0.04
over 0.45 0.05 11.3 When the dimensions of the material to be tested will
Aluminum to 0.15, incl –0.005 permit, the tension test specimens shall be machined to the
+0.01 form and dimensions of the standard 2-in. gauge length tension
over 0.15 to 0.50, incl 0.05
over 0.50 to 0.80, incl 0.07 test specimens described in Test Methods and Definitions A370
Vanadium to 0.10 incl 0.01 if inch-pound units are specified or the standard 62.5 mm
over 0.10 to 0.25, incl 0.02 gauge length tension test specimens described in the applicable
over 0.25 to 0.50, incl 0.03
minimum value specified, 0.01 track of Test Methods A1058 if SI units are specified.
under minimum limit only 11.3.1 In the case of small sections, which will not permit
Cerium to 0.20, incl 0.01 taking the standard test specimen described in 11.3, the subsize
Selenium to 0.35, incl 0.001
Tungsten to 0.50, incl 0.02 round or strip specimen shall be machined as described in the
over 0.50 to 1.00, incl 0.03 test methods being used. The tension test specimen shall be as
over 1.00 to 2.00, incl 0.05 large as feasible.
over 2.00 to 4.00, incl 0.06
Lead to 0.35, incl 0.03
Zirconium to 0.01, incl 0.005 12. Impact Requirements
Boron to 0.015 incl 0.0005
Tin to 0.010, incl C 12.1 The part shall conform to the impact requirements
C
Arsenic to 0.010, incl
C
prescribed in the product specification.
Antimony to 0.003, incl
A
This table does not apply to heat analysis.
12.2 Sampling for impact testing shall conform to the
B
Product analysis limits for cobalt under 0.05 % have not been established and the product specification.
producer should be consulted for those limits.
C
No over tolerance allowed. 12.3 Notched-bar impact specimens shall be simple-beam,
Charpy-type A with a V-notch in accordance with Test Methods

4
 A960/A960M − 23
and Definitions A370 if the inch-pound units are specified or 15.3 Fittings supplied under this specification shall be
Test Methods A1058 if the M suffix (SI Units) standard is examined visually. Selected typical surface discontinuities
specified. Standard specimens 10 by 10 mm in cross section shall be explored for depth. Unless otherwise specified in the
shall be used unless the material to be tested is of insufficient purchase order, the following shall apply.
thickness, in which case the largest obtainable standard subsize 15.3.1 Fittings conforming to ASME B16.9, MSS-SP-43,
impact specimens shall be used. When the size or shape of the and MSS-SP-95 shall be free of surface discontinuities that
finished fittings is insufficient to permit obtaining the smallest penetrate more than 5 % of the specified nominal wall
standard subsize impact specimens, an impact test by the fitting thickness, except as defined in 15.3.3 and 15.3.4. Fittings
manufacturer will not be required. conforming to ASME B16.11, MSS-SP-79, MSS-SP-83, and
MSS-SP-97 shall be free of surface discontinuities that pen-
13. Hydrostatic Test Requirements etrate more than 5 % of the actual wall thickness at the point of
13.1 Parts manufactured under this specification shall be interest, or 1⁄16 in. [1.6 mm], whichever is less, except as
capable of passing a hydrostatic test compatible with the rating defined in 15.3.4. Fittings conforming to MSS-SP-75 shall be
of the specified matching pipe of equivalent material. Such a free of surface discontinuities that penetrate more than 61⁄2 %
test shall be conducted only when specified in the purchase of the specified nominal wall thickness.
order or when the hydrostatic test Supplementary Requirement 15.3.2 Surface discontinuities deeper than 5 % of the speci-
is invoked by the purchaser. fied nominal or actual wall thickness as applicable, except as
defined in 15.3.3 and 15.3.4, shall be removed by the manu-
14. Rework facturer by machining or grinding to sound metal, and the
14.1 When one or more representative test specimens or repaired areas shall blend smoothly into the contour of the
retest specimens do not conform to the requirements specified finished fitting. Surface discontinuities on fittings conforming
in the product specification for the tested characteristic, the lot to MSS-SP-75 shall be removed or repaired in accordance with
of material represented by the test specimen may be reworked the requirements of that standard. Except for fittings conform-
according to the following requirements. ing to MSS-SP-75, the wall thickness at all points shall be at
14.1.1 If previously tested in the untreated condition, the least the specified minimum wall thickness, or 871⁄2 % of the
product may be reworked by heat treatment, and subsequently specified nominal wall thickness and the diameters shall be
retested, in accordance with the product specification. within the limits specified in the applicable dimensional
14.1.2 If previously tested in the heat treated condition, the standards.
product may be reworked by reheat treatment, and subse- 15.3.3 Surface checks (fish scale) deeper than 1⁄64 in. [0.4
quently retested, in accordance with the product specification. mm] shall be removed.
15.3.4 Mechanical marks deeper than 1⁄16 in. [1.6 mm] shall
15. Surface Finish, Appearance, and Corrosion be removed.
Protection 15.3.5 When the removal of a surface discontinuity reduces
15.1 The parts shall conform to the dimensions, tolerances the wall thickness below the specified minimum wall thickness
and finish as specified in the purchaser’s order and to the at any point, the fitting shall be subject to rejection or to repair
individual ASTM product specification. as provided in Section 16, or in accordance with MSS-SP-75
15.2 The finished parts shall be cleaned to remove all scale for fittings conforming to that standard.
and processing compounds prior to the final surface examina-
tion. The cleaning process shall not injure the surface finish, 16. Repair by Welding
material properties, or the metallurgical structure. 16.1 The purchaser may require the supplier to submit
15.2.1 The surface finish shall allow the detection of imper- proposed weld repairs for approval by invoking the appropriate
fections that can be disclosed by visual inspection. Supplementary Requirement in the purchase order.
15.2.2 The cleaned parts shall be protected to prevent
recontamination. 16.2 If the purchaser does not require prior approval of the
15.2.2.1 Exterior and interior surfaces of carbon, low, and proposed weld repairs, these repairs shall be permitted at the
intermediate alloy steel fittings shall have a corrosion protec- discretion of the supplier. All weld repairs shall be performed
tive coating. Unless otherwise specified by the purchaser, the in accordance with the following limitations and requirements.
type of surface protection shall be at the option of the 16.2.1 The welding procedure, welders and operators shall
manufacturer. be qualified in accordance with Section IX of the ASME Boiler
15.2.2.2 Stainless steel and nickel alloy fittings need not be and Pressure Vessel Code. The composition of the weld deposit
coated. Unmachined surfaces of stainless steel fittings shall be shall be compatible with the composition of the material being
passivated by exposure to an acid bath, or electropolished. welded.
15.2.3 Protective coatings on parts subsequently subjected 16.2.2 Defects shall be completely removed prior to weld-
to socket welds or butt welds shall be suitable for welding ing by machining, chipping or grinding to sound metal.
without removal of the coating. Threaded fittings shall be Removal of these defects shall be verified by magnetic particle
capable of installation without the removal of the coating. examination in accordance with Guide E709 or liquid penetrant
15.2.4 When specified in the purchase order, parts may be inspection in accordance with Test Method E165/E165M, as
furnished in the as-formed condition. applicable.

5
 A960/A960M − 23
16.2.3 After repair welding, the welded area shall be ma- tags, box labels, etc. for identification when per piece marking
chined or ground smooth to the original contour and shall be is not practical due to size or shape.
completely free of defects as verified by magnetic particle 19.2 The Standard Marking System of Valves, Fittings,
examination in accordance with Guide E709 or liquid penetrant Flanges and Unions MSS-SP-25 shall be followed except the
inspection in accordance with Test Method E165/E165M, as word “steel” shall not be substituted for the specification grade.
applicable.
16.2.4 Repair welding shall not exceed 10 % of the external 19.3 Product marking shall conform to the additional
surface area of the part, or 331⁄3 % of the wall thickness of the requirements, if any, invoked in the product specification or
finished product, or 3⁄8 in. [10 mm] deep maximum at the purchase order.
location of the repair, without prior approval of the purchaser. 20. Certification
16.2.5 Weld repaired material or parts, or both, shall be
marked “RW” when required by the product specification. 20.1 A test report and certificate of compliance are required.

16.3 The weld repair shall conform to the additional 20.2 Test reports shall include the product specification
requirements, if any, invoked in the product specification. number and year/date of issue, the results of all tests required
by this specification, and the purchaser order, and shall be
17. Inspection traceable to the part represented.
17.1 The supplier shall provide the purchaser’s inspector 20.3 A single document containing the test report informa-
with all reasonable facilities necessary to satisfy him that the tion and certificate of compliance information may be used.
material is being produced and furnished in accordance with 20.4 A certificate printed from or used in electronic data
this specification and the applicable product specification. Site interchange (EDI) transmission shall be regarded as having the
inspection by the purchaser shall not interfere unnecessarily same validity as a counterpart printed in the certifier’s facility.
with the supplier’s operations. The content of the EDI transmitted document shall conform to
any existing EDI agreement between the purchaser and the
18. Rejection and Rehearing supplier.
18.1 Samples representing material rejected by the pur- 20.5 Not withstanding the absence of a signature, the
chaser shall be preserved until disposition of the claim has been organization submitting either a printed certificate or an EDI
agreed to between the supplier and the purchaser. transmitted certificate is responsible for the content of the
19. Marking report.
19.1 Each piece shall be legibly marked in a position as not 21. Packaging, Marking and Loading for Shipment
to injure the usefulness of the fitting with the product specifi- 21.1 Packaging, marking, and loading for shipment shall be
cation number, grade or marking symbol, class, certifying in accordance with Practices A700.
organization’s name or symbol, the heat number or heat
identification, size, and schedule number or wall thickness, if 22. Keywords
applicable. Dual or multiple marking with the product speci- 22.1 austenitic stainless steel; corrosive service applica-
fication number, grade or marking symbol, and class is tions; ferritic/austenitic stainless steel; ferritic stainless steel;
acceptable provided the material meets all the requirements high strength low alloy steel; martensitic stainless steel; piping
with which it is marked. It is not required to mark the product applications; pressure containing parts; pressure vessel service;
with the specification year and date of issue. When size or stainless steel fittings; temperature service applications-
shape does not permit the inclusion of all the required marking elevated; temperature service applications-low; temperature
as described, see 19.2. Manufacturer can also choose the use of service applications-moderate

SUPPLEMENTARY REQUIREMENTS

These requirements shall not be considered unless specified in the order, in which event, the
supplementary requirements specified shall be made at the place of manufacture, unless otherwise
agreed upon, at the purchaser’s expense. The test specified shall be witnessed by the purchaser’s
inspector before shipment of material, if so specified in the order. The rationale for beginning the
section numbering with S50 is to eliminate the possibility of confusion with supplementary
requirements existing in individual product specifications.

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S50. Product Analysis (see Note S50.1) S56. Special Heat Treatment
S50.1 A product analysis shall be made from each heat of S56.1 A special heat treatment shall be applied as agreed
base metal and, if of welded construction, from each lot upon between the manufacturer and the purchaser.
number of welding material of the fittings offered for delivery.
The analysis shall conform to the requirements specified in S57. Hardness Test
Section 8. S57.1 If actual hardness testing of fittings is required, the
frequency and the method used shall be as agreed upon
S51. Tension Test (see Note S50.1) between the manufacturer and the purchaser.
S51.1 One tension test shall be made on one fitting or
representative test piece (See Note S50.2) per lot (See Note S58. Special Fittings
S50.3) of fittings. If the fittings are of welded construction, the S58.1 Partial compliance fittings of size or shape not con-
tension specimen shall include the weld and shall be prepared forming to the dimensional requirements of ASME B16.9,
so that the weld is at the midlength location of the specimen. B16.11, MSS-SP-79, MSS-SP-83, MSS-SP-95, and MSS-
However, in no case shall the tensile properties of the finished SP-97 shall meet all other requirements of the individual
fitting be less than the requirements listed in the individual product specification. In addition to the marking required by
product specification. Section 19, the grade designation symbol of the individual
NOTE S50.1—If the result of any of the tests specified in Supplementary product specification shall be followed by the symbol “S58”.
Requirements S50, S51, or S63 do not conform to requirements, retests
may be made at the manufacturer’s expense on additional fittings or S59. Heat Treatment of Concentric Reducers
representative test pieces of double the original number from the same
heat or lot as defined in Supplementary Requirements S50, S51, or S63, S59.1 Concentric reducers formed by local heating of the
each of which shall conform to the requirements specified. fitting shall be subsequently annealed, normalized, or normal-
NOTE S50.2—Where the test specimen for the tension or intergranular ized and tempered.
corrosion bend test cannot be taken from a fitting due to size limitations,
a representative test piece shall be obtained. The test piece shall be from S60. Marking Small Fittings
the same lot it represents and shall have approximately the same amount
of working. In addition, these pieces representing fittings manufactured S60.1 For small products where the space for marking is
from bars, plate, or forgings shall have a cross section equal to the greatest less than 1 in. [25 mm] in any direction, test reports are
cross section of the fitting, and test pieces representing fittings manufac-
tured from pipe shall have an outside diameter and wall thickness equal to
mandatory and marking may be restricted to only such symbols
those of the fitting. The test piece for fittings of welded construction shall or codes as are necessary to identify the parts with test reports.
be prepared to the same weld procedures and from the same heat of S60.2 When the configuration or size does not permit
materials as the fittings it represents. marking directly on the fitting, the marking method shall be a
NOTE S50.3—A lot shall consist of all fittings of the same type, size, and matter of agreement between the manufacturer and the pur-
wall thickness, manufactured from one heat of material (and, if fabrication
welding is performed using one lot number of electrode or one heat of
chaser.
weld wire), and heat treated using the same heat-treat cycle in either a
continuous or batch-type furnace controlling within a range of 50 °F [28 S61. Phosphorous and Sulphur Content
°C] and equipped with recording pyrometers so that complete records of S61.1 The phosphorous and sulphur contents of the fittings
heat treatment are available.
shall not exceed 0.025 %.
S52. Liquid Penetrant Examination S62. Ultrasonic Test
S52.1 All surfaces shall be liquid penetrant examined in S62.1 Each fitting or the raw material from which the fitting
accordance with Test Method E165/E165M. Acceptance limits is made shall be ultrasonically tested to determine its sound-
shall be specified by the purchaser. Personnel performing the ness. The method, where applicable, shall be in accordance
examination shall be qualified in accordance with SNT-TC-1A- with Practice A388/A388M. Acceptance limits shall be speci-
1988 or later. fied by the purchaser. Personnel performing NDE examinations
shall be qualified in accordance with SNT-TC-1A-1988 or
S53. Magnetic-Particle Examination later.
S53.1 All accessible surfaces shall be magnetic particle S62.2 Each fitting or the raw material from which each
examined in accordance with Guide E709. Acceptance limits fitting is made shall be ultrasonically tested to determine its
shall be specified by the purchaser. Personnel performing the soundness. The method, where applicable, shall be in accor-
examination shall be qualified in accordance with SNT-TC-1A- dance with Practice E213. Acceptable limits shall be specified
1988 or later. by the purchaser. Personnel performing the examination shall
be qualified in accordance with SNT-TC-1A-1988 or later.
S54. Hydrostatic Test S63. Intergranular Corrosion Bend Test (see Note S50.1)
S54.1 A hydrostatic test shall be applied as agreed upon S63.1 An intergranular corrosion bend test shall be made on
between the manufacturer and purchaser. one fitting or representative test piece (See Note S50.2) per lot
(See Note S50.3) of fittings. If the fittings are of welded
S55. Bar Stock Fittings construction, the bend specimen shall include the weld and be
S55.1 Bar stock fittings shall not be permitted. prepared so that the weld is at the midlength location of the

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 A960/A960M − 23
specimen. Specimens containing a weld shall be bent so that S70.2 Acceptance criteria shall be in accordance with
the location of weld is at the point of maximum bend. The S69.2.
method of testing shall be in accordance with Practice E of S70.3 Personnel performing NDE examinations shall be
Practices A262 (rapid screening is not allowed) or Practice Z of qualified in accordance with SNT-TC-1A-1988 or later.
Practices A763, as applicable.
S71. Product Marking
S64. Photomicrographs S71.1 Weld repaired parts shall be marked “S71”.
S64.1 Photomicrographs at 100 diameters shall be made for
information only of the actual base metal structure from one S72. Nondestructive Electromagnetic (Eddy-Current) Test
fitting as furnished in each lot. The photomicrographs shall be S72.1 For eddy-current testing, the calibration tube shall
identified as to fitting size, wall thickness, lot identification, contain, at the option of the manufacturer, any one of the
and heat. The definition of “lot” shall be as specified by the following discontinuities placed in the weld to establish a
purchaser. minimum sensitivity level for rejection.
S72.2 Drilled Hole—A hole not larger than 0.031 in. [0.79
S65. Surface Finish mm] in diameter shall be drilled radially and completely
S65.1 Machined surfaces shall have a maximum roughness through the tube wall, with care being taken to avoid distortion
of 250 µin. AARH [6.3 µm]. All other surfaces shall be suitable of the tube while drilling.
for ultrasonic testing. S72.3 Transverse Tangential Notch—Using a round tool or
file with a 1⁄4-in. [6-mm] diameter, a notch shall be filed or
S66. Repair Welding milled tangential to the surface and transverse to the longitu-
S66.1 No weld repair shall be permitted without prior dinal axis of the tube. The notch shall have a depth not
approval of the purchaser. exceeding 121⁄2 % of the specified wall thickness of the tube or
0.004 in. [0.102 mm], whichever is greater.
S67. Charpy V-Notch Test S72.4 Longitudinal Notch—A notch 0.031 in. [0.79 mm] or
S67.1 Charpy V-notch test shall be made as specified on the less in width shall be machined in a radial plane parallel to the
order. The test temperature, acceptance criteria, number of tube axis on the outside surface of the tube, to have a depth not
tests, and location of tests (whether from base metal, weld exceeding 121⁄2 % of the specified wall thickness of the tube or
metal, or heat affected zone of welds) shall be specified. 0.004 in. [0.102 mm], whichever is greater. The length of the
notch shall be compatible with the testing method.
S68. Special Notch Toughness S72.5 Fittings producing a signal equal to or greater than the
S68.1 The impact test temperature or acceptance values, or calibration defect shall be subject to rejection. To be accepted,
both, shall be as agreed upon, but only with respect to lower after rework, the fittings must pass the same test to which it
temperatures or higher energy values. was originally subjected.
S72.6 Personnel performing NDE examinations shall be
S69. Magnetic Particle Examination—Weld Metal qualified in accordance with SNT-TC-1A-1988 or later.
S69.1 All accessible welds shall be examined in accordance
with Guide E709. Accessible is defined as all outside surfaces, S73. Weld Metal Analysis
all inside fitting surfaces 24 in. [610 mm] in diameter and S73.1 Analysis of weld metal shall be reported.
greater, and inside fitting surfaces less than 24 in. [610 mm] in
diameter, for a distance of one diameter from the ends. S74. Welding Procedure Test Record
S69.2 Acceptance Criteria—The following indications are S74.1 A welding procedure test record shall be furnished.
unacceptable:
S69.2.1 Any cracks and linear indications, S75. Chemical Analysis of Remelted Steel
S69.2.2 Rounded indications with dimensions greater than S75.1 Each remelted ingot shall be assigned a unique
3⁄16 in. [4.8 mm], identification number.
S69.2.3 Four or more indications in any line separated by S75.2 A chemical analysis shall be made from each re-
1⁄16 in. [1.6 mm], melted ingot.
S69.2.4 Ten or more indications located in any 6 in.2 [4000
mm2] of surface, with the major dimensions not to exceed 6 in. S76. Electropolished Austenitic Grades
[150 mm] when the major dimension is oriented so that the S76.1 All electropolished austenitic fittings shall be of a
area includes the maximum number of indications being cleanliness according to Specification A967/A967M.
evaluated. S76.2 Details concerning which test method of Specifica-
S69.3 Personnel performing NDE examinations shall be tion A967/A967M are to be a matter of agreement between the
qualified in accordance with SNT-TC-1A-1988 or later. manufacturer and the purchaser.
S70. Liquid Penetrant Examination of Weld Metal S77. Positive Material Identification Examination
S70.1 All accessible surfaces of fittings shall be examined S77.1 Fittings shall be examined to assure that the pur-
in accordance with Test Method E165/E165M. Accessible is chaser is receiving fittings of the correct material grade prior to
defined in S69. shipment of the fittings. This examination is to assure that no

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 A960/A960M − 23
material grade mix-up has happened during manufacturing and S78.5 The minimum C content based on heat analysis shall
marking of the fittings. be 0.18 wt %. The maximum C content shall be as specified in
S77.2 Fittings shall receive a Positive Material Identifica- the appropriate material specification.
tion examination using the methods of Guide E1916. S78.6 Repair welds shall not be made with E60XX elec-
S77.3 The quantity examined shall be 100 % of the fittings. trodes. Use of E70XX electrodes is recommended and the
S77.4 All fittings that are not of the correct material grade resulting weld chemistry should meet the same chemistry
shall be rejected. criteria as the base metal as listed above.
S77.5 The method of fitting marking after this examination S78.7 In addition to the requirements of product marking of
shall be agreed upon between the manufacturer and purchaser. the specification, an "HF" stamp or marking shall be provided
on each component to identify that component complies with
S78. Requirements for Carbon Steel Products for Concen- this supplementary requirement.
trated Hydrofluoric Acid Service
S79 Pressure Equipment Directive—Mechanical Testing
S78.1 The maximum carbon equivalent based on heat
analysis shall be as follows: S79.1 Charpy impact testing shall be done at the lowest
Maximum section thickness less than or equal CE maximum = 0.43
scheduled operating temperature, but not higher than 68 °F [20
to 1 in. °C].
Maximum section thickness greater than 1 in. CE maximum = 0.45 S79.2 The frequency of impact testing shall be the same as
S78.2 Determine the carbon equivalent (CE) as follows: that specified in the product specification for the tension test,
CE = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15 with three individual Charpy test specimens for each required
S78.3 Vanadium and Niobium maximum content based on tension test.
heat analysis shall be: S79.3 The minimum impact absorption energy for the
Maximum Vanadium = 0.02 wt % Charpy test specimen shall be at least 20 ft-lb [27 J].
Maximum Niobium = 0.02 wt % S79.4 The minimum elongation in the tension test shall be
Maximum Vanadium plus Niobium = 0.03 wt % measured on a gauge length of five times the diameter of the
(Note Niobium = Columbium) test specimen, and shall not be less than 14 %.
S78.4 The maximum composition based on heat analysis of S79.5 Impact and tension test results shall be included in the
Ni + Cu shall be 0.15 wt %. product certification.

ANNEXES

(Mandatory Information)

A1. REQUIREMENTS FOR THE INTRODUCTION OF NEW MATERIALS

A1.1 New materials may be proposed for inclusion in A1.1.3 The application shall be accompanied by test data as
specifications referencing this specification of general require- required by the applicable specification. Test data from a
ments subject to the following conditions: minimum of three test lots, as defined by the specification, each
A1.1.1 Application for the addition of a new grade to a from a different heat, shall be furnished.
specification shall be made to the chair of the subcommittee A1.1.4 The application shall provide recommendations for
that has jurisdiction over that specification.
all requirements appearing in the applicable specification.
A1.1.2 The application shall be accompanied by a statement
from at least one user indicating that there is a need for the new A1.1.5 The application shall state whether the new grade is
grade to be included in the applicable specification. covered by patent.

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 A960/A960M − 23

A2. REQUIREMENTS FOR THE INTRODUCTION OF MATERIALS FROM OTHER A01 OR B02.07 SPECIFICATIONS

A2.1 Wrought materials that are already covered by another A2.1.2 The chemical requirements, the specified mechani-
A01 or B02.07 specification may be proposed for inclusion in cal properties, and the heat treatment requirements of the grade
specifications referencing this specification of general require- being added shall be the same as those for the grade in the A01
ments subject to the following conditions: or A01 specification in which the grade is presently covered.
A2.1.1 Application for the addition of a grade that is already A2.1.3 The application shall provide recommendations for
covered in another A01 or B02.07 specification shall be made all requirements appearing in the applicable specification.
to the chair of the subcommittee that has jurisdiction over that A2.1.4 The application shall state whether or not the grade
specification. is covered by patent.

SUMMARY OF CHANGES

Committee A01 has identified the location of selected changes to this standard since the last issue
(A960/A960M – 20) that may impact the use of this standard. (Approved May 1, 2023.)

(1) Added definition of longitudinal axis to 3.1.6.

(2) Revised 6.2 to clarify what parts may be machined directly
from bar or seamless tubular material.

ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned
in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk
of infringement of such rights, are entirely their own responsibility.

This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and
if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards
and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the
responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should
make your views known to the ASTM Committee on Standards, at the address shown below.

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