ASTM A312/A312M-24

Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes

ABSTRACT
This guide covers standard specification for seamless, straight-seam welded, and cold worked welded austenitic stainless steel pipe intended for high-temperature and general corrosive service. Several grades of steel shall conform to the required chemical composition for carbon, manganese, phosphorus, sulfur, silicon, chromium, nickel, molybdenum, titanium, columbium, tantalum, nitrogen, vanadium, copper, cerium, boron, aluminum, and others. All pipes shall be furnished in the heat-treated condition in accordance with the required heat treating temperature and cooling/testing requirements. Tensile properties of the material shall conform to the prescribed tensile strength and yield strength. The steel pipe shall undergo mechanical tests such as transverse or longitudinal tension test and flattening test. Grain size determination and weld decay tests shall be performed. Each pipe shall also be subjected to the nondestructive electric test or the hydrostatic test.
SCOPE
1.1 This specification2 covers seamless, straight-seam welded, and heavily cold worked welded austenitic stainless steel pipe intended for high-temperature and general corrosive service.  
1.2 Grades TP304H, TP309H, TP309HCb, TP310H, TP310HCb, TP316H, TP321H, TP347H, and TP348H are modifications of Grades TP304, TP309Cb, TP309S, TP310Cb, TP310S, TP316, TP321, TP347, and TP348, and are intended for service at temperatures where creep and stress rupture properties are important.  
1.3 Optional supplementary requirements are provided for pipe where a greater degree of testing is desired. These supplementary requirements call for additional tests to be made and, when desired, it is permitted to specify in the order one or more of these supplementary requirements.  
1.4 Table X1.1 lists the standardized dimensions of welded and seamless stainless steel pipe as shown in ASME B36.19. These dimensions are also applicable to heavily cold worked pipe. Pipe having other dimensions is permitted to be ordered and furnished provided such pipe complies with all other requirements of this specification.  
1.5 Grades TP321 and TP321H have lower strength requirements for pipe manufactured by the seamless process in nominal wall thicknesses greater than 3/8 in. [9.5 mm].  
1.6 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. The inch-pound units shall apply unless the “M” designation of this specification is specified in the order.  
Note 1: The dimensionless designator NPS (nominal pipe size) has been substituted in this standard for such traditional terms as “nominal diameter,” “size,” and “nominal size.”  
1.7 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: 29-Feb-2024
• ICS: 23.040.10 - Iron and steel pipes
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.10 - Stainless and Alloy Steel Tubular Products

Relations

• Replaces: ASTM A312/A312M-22a - Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes
• Effective Date: 01-Mar-2024
• Refers: ASTM A941-24 - Standard Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
• Effective Date: 01-Mar-2024
• Refers: ASTM A370-24 - Standard Test Methods and Definitions for Mechanical Testing of Steel Products
• Effective Date: 01-Mar-2024
• Refers: ASTM A370-23 - Standard Test Methods and Definitions for Mechanical Testing of Steel Products
• Effective Date: 15-Sep-2023
• Refers: ASTM A941-23 - Standard Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
• Effective Date: 01-May-2023
• Referred By: ASTM B677-23 - Standard Specification for Nickel-Iron-Chromium-Molybdenum, Iron-Nickel-Chromium-Molybdenum-Copper, and Nickel-Iron-Chromium-Molybdenum-Nitrogen Seamless Pipe and Tube
• Effective Date: 01-Mar-2024
• Referred By: ASTM F2929-17(2021) - Standard Specification for Crosslinked Polyethylene (PEX) Tubing of 0.070 in. Wall and Fittings for Radiant Heating Systems up to 75 psig
• Effective Date: 01-Mar-2024
• Referred By: ASTM F2080-23 - Standard Specification for Cold-Expansion Fittings with Metal Compression-Sleeves for Crosslinked Polyethylene (PEX) Pipe and SDR9 Polyethylene of Raised Temperature (PE-RT) Pipe
• Effective Date: 01-Mar-2024
• Referred By: ASTM C1847-21 - Standard Specification for Direct Buried Pre-Insulated and Jacketed Polyurethane Bonded Low Temperature Hot Water Piping Systems
• Effective Date: 01-Mar-2024
• Referred By: ASTM F2014-00(2019) - Standard Specification for Non-Reinforced Extruded Tee Connections for Piping Applications
• Effective Date: 01-Mar-2024
• Referred By: ASTM F2015-00(2019) - Standard Specification for Lap Joint Flange Pipe End Applications
• Effective Date: 01-Mar-2024
• Referred By: ASTM F1387-23 - Standard Specification for Performance of Piping and Tubing Mechanically Attached Fittings
• Effective Date: 01-Mar-2024
• Referred By: ASTM F1545-15a(2021) - Standard Specification for Plastic-Lined Ferrous Metal Pipe, Fittings, and Flanges
• Effective Date: 01-Mar-2024
• Referred By: ASTM A733-16(2022) - Standard Specification for Welded and Seamless Carbon Steel and Austenitic Stainless Steel Pipe Nipples
• Effective Date: 01-Mar-2024
• Referred By: ASTM F1076-19 - Standard Practice for Expanded Welded and Silver Brazed Socket Joints for Pipe and Tube
• Effective Date: 01-Mar-2024

Overview

ASTM A312/A312M-24 is the internationally recognized standard specification for seamless, straight-seam welded, and heavily cold worked austenitic stainless steel pipes. Established by ASTM International, this standard provides comprehensive requirements for pipes intended for high-temperature and general corrosive services, making it essential for industries that demand high performance and durability. The standard covers several grades of austenitic stainless steel and specifies requirements for chemical composition, mechanical properties, manufacturing, testing, and marking. It is widely referenced in construction, chemical processing, oil and gas, energy production, and numerous other sectors where reliable stainless steel piping is critical.

Key Topics

• Product Scope: Covers seamless and welded austenitic stainless steel pipes, including special provisions for heavily cold worked (HCW) welded pipes.
• Service Applications: Primarily designed for use in high-temperature and general corrosive service environments. Certain grades (such as TP304H, TP321H, TP347H) are specifically modified for enhanced performance at elevated temperatures, where resistance to creep and stress rupture is essential.
• Grades and Compositions: Includes an extensive list of alloys (e.g., TP304, TP316, TP321, TP347, TP348, and their “H” high-temperature variants), each conforming to strict chemical composition limits.
• Mechanical Properties: Specifies minimum tensile strength, yield strength, and elongation for various grades, ensuring the pipes’ durability and load-bearing capability.
• Manufacturing and Heat Treatment: Pipes must be heat-treated according to prescribed temperatures and cooling methods (e.g., water quenching or rapid cooling). Both hot and cold finishing processes are permitted.
• Testing and Inspection Requirements: Detailed mechanical testing procedures (tension and flattening tests), non-destructive electric or hydrostatic testing, grain size assessments, and weld decay tests ensure pipe integrity and quality.
• Dimensional Standards: Refers to ASME B36.19 for standardized dimensions, with allowances for custom sizes when compliant with all relevant requirements.
• Marking and Certification: Pipes must be clearly marked with grade, heat number, testing status, and other identifiers per Section 17, ensuring complete traceability.

Applications

ASTM A312/A312M-24 austenitic stainless steel pipes are employed across a broad spectrum of industries due to their exceptional corrosion resistance and mechanical performance. Common applications include:

• Petrochemical and Chemical Processing: Used for transporting highly reactive fluids and aggressive chemicals, thanks to their outstanding corrosion resistance.
• Oil & Gas Sector: Provides safe, high-pressure fluid conveyance for both upstream and downstream operations.
• Power Generation: Essential in high-temperature environments such as boiler tubes and superheater piping.
• Pharmaceutical and Food Processing: Meeting hygienic standards where product purity is crucial.
• Water Treatment: Suitable for environments with corrosive or high-temperature water.
• General Industry: Used in construction, infrastructure, shipbuilding, and any scenario requiring dependable stainless steel piping.

Related Standards

For complete compliance and optimal integration, the following related standards and documents may be referenced:

• ASME B36.19 - Stainless Steel Pipe dimensions.
• ASME Boiler and Pressure Vessel Code (BPVC) Section II and Section VIII - Requirements for pressure vessel applications.
• ASTM A999/A999M - General requirements for alloy and stainless steel pipe.
• ASTM A262 - Practices for detecting susceptibility to intergranular attack in austenitic stainless steels.
• ASTM A370 - Test methods for mechanical testing of steel products.
• AWS A5.9 - Specification for welding rods and electrodes for corrosion-resistant Chromium and Chromium-Nickel steel.

Keywords: austenitic stainless steel pipe, seamless stainless steel pipe, welded stainless steel pipe, ASTM A312, high-temperature service, corrosive environments, industrial piping standards, mechanical testing, chemical composition, pressure piping.

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: A312/A312M − 24 Used in USDOE-NE standards
Standard Specification for
Seamless, Welded, and Heavily Cold Worked Austenitic
Stainless Steel Pipes
This standard is issued under the fixed designation A312/A312M; 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.
NOTE 1—The dimensionless designator NPS (nominal pipe size) has
1. Scope*
been substituted in this standard for such traditional terms as “nominal
1.1 This specification covers seamless, straight-seam
diameter,” “size,” and “nominal size.”
welded, and heavily cold worked welded austenitic stainless
1.7 This international standard was developed in accor-
steel pipe intended for high-temperature and general corrosive
dance with internationally recognized principles on standard-
service.
ization established in the Decision on Principles for the
1.2 Grades TP304H, TP309H, TP309HCb, TP310H,
Development of International Standards, Guides and Recom-
TP310HCb, TP316H, TP321H, TP347H, and TP348H are
mendations issued by the World Trade Organization Technical
modifications of Grades TP304, TP309Cb, TP309S, TP310Cb,
Barriers to Trade (TBT) Committee.
TP310S, TP316, TP321, TP347, and TP348, and are intended
for service at temperatures where creep and stress rupture
2. Referenced Documents
properties are important.
2.1 ASTM Standards:
1.3 Optional supplementary requirements are provided for
A262 Practices for Detecting Susceptibility to Intergranular
pipe where a greater degree of testing is desired. These
Attack in Austenitic Stainless Steels
supplementary requirements call for additional tests to be made
A370 Test Methods and Definitions for Mechanical Testing
and, when desired, it is permitted to specify in the order one or
more of these supplementary requirements. of Steel Products
A941 Terminology Relating to Steel, Stainless Steel, Related
1.4 Table X1.1 lists the standardized dimensions of welded
Alloys, and Ferroalloys
and seamless stainless steel pipe as shown in ASME B36.19.
A999/A999M Specification for General Requirements for
These dimensions are also applicable to heavily cold worked
Alloy and Stainless Steel Pipe
pipe. Pipe having other dimensions is permitted to be ordered
A1016/A1016M Specification for General Requirements for
and furnished provided such pipe complies with all other
Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless
requirements of this specification.
Steel Tubes
1.5 Grades TP321 and TP321H have lower strength require-
E112 Test Methods for Determining Average Grain Size
ments for pipe manufactured by the seamless process in
E381 Method of Macroetch Testing Steel Bars, Billets,
nominal wall thicknesses greater than ⁄8 in. [9.5 mm].
Blooms, and Forgings
1.6 The values stated in either SI units or inch-pound units
E527 Practice for Numbering Metals and Alloys in the
are to be regarded separately as standard. Within the text, the
Unified Numbering System (UNS)
SI units are shown in brackets. The values stated in each
2.2 ASME Standards:
system may not be exact equivalents; therefore, each system
B1.20.1 Pipe Threads, General Purpose
shall be used independently of the other. Combining values
B36.10M Welded and Seamless Wrought Steel Pipe
from the two systems may result in non-conformance with the
B36.19 Stainless Steel Pipe
standard. The inch-pound units shall apply unless the “M”
ASME Boiler and Pressure Vessel Code : Section VIII
designation of this specification is specified in the order.
This specification is under the jurisdiction of ASTM Committee A01 on Steel,
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee For referenced ASTM standards, visit the ASTM website, www.astm.org, or
A01.10 on Stainless and Alloy Steel Tubular Products. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Current edition approved March 1, 2024. Published March 2024. Originally Standards volume information, refer to the standard’s Document Summary page on
approved in 1948. Last previous edition approved in 2022 as A312/A312M – 22a. the ASTM website.
DOI: 10.1520/A0312_A0312M-24. Available from American Society of Mechanical Engineers (ASME), ASME
For ASME Boiler and Pressure Vessel Code applications see related Specifi- International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
cation SA-312 in Section II of that Code. www.asme.org.
*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
A312/A312M − 24
2.3 AWS Standard: 6.2 Heat Treatment—All pipe shall be furnished in the
A5.9 Corrosion-Resisting Chromium and Chromium-Nickel heat-treated condition in accordance with the requirements of
Steel Welding Rods and Electrodes Table 2. Alternatively, for seamless pipe, immediately follow-
ing hot forming while the temperature of the pipes is not less
2.4 Other Standard:
than the minimum solution treatment temperature specified in
SAE J1086 Practice for Numbering Metals and Alloys
Table 2, pipes shall be individually quenched in water or
(UNS)
rapidly cooled by other means (direct quenched).
3. Terminology
7. Chemical Composition
3.1 Definitions:
7.1 The steel shall conform to the requirements as to
3.1.1 The definitions in Specification A999/A999M and
chemical composition prescribed in Table 1.
Terminology A941 are applicable to this specification.
8. Product Analysis
4. Ordering Information
8.1 At the request of the purchaser, an analysis of one billet
4.1 Orders for material to this specification shall conform to
or one length of flat-rolled stock from each heat, or two pipes
the requirements of the current edition of Specification A999/
from each lot shall be made by the manufacturer. A lot of pipe
A999M.
shall consist of the following number of lengths of the same
5. General Requirements
size and wall thickness from any one heat of steel:
NPS Designator Lengths of Pipe in Lot
5.1 Material furnished under this specification shall con-
Under 2 400 or fraction thereof
form to the applicable requirements of the current edition of
2 to 5 200 or fraction thereof
Specification A999/A999M unless otherwise provided herein.
6 and over 100 or fraction thereof
8.2 The results of these analyses shall be reported to the
6. Materials and Manufacture
purchaser or the purchaser’s representative, and shall conform
6.1 Manufacture:
to the requirements specified in Section 7.
6.1.1 The pipe shall be manufactured by one of the follow-
8.3 If the analysis of one of the tests specified in 8.1 does
ing processes:
not conform to the requirements specified in Section 7, an
6.1.2 Seamless (SML) pipe shall be made by a process that
analysis of each billet or pipe from the same heat or lot may be
does not involve welding at any stage of production.
made, and all billets or pipe conforming to the requirements
6.1.3 Welded (WLD) pipe shall be made using an automatic
shall be accepted.
welding process with no addition of filler metal during the
welding process.
9. Permitted Variations in Wall Thickness
6.1.4 Heavily cold-worked (HCW) pipe shall be made by
9.1 In addition to the implicit limitation of wall thickness
applying cold working of not less than 35 % reduction in
for seamless pipe imposed by the limitation on weight in
thickness of both wall and weld to a welded pipe prior to the
Specification A999/A999M, the wall thickness for seamless
final anneal. No filler shall be used in making the weld. Prior
and welded pipe at any point shall be within the tolerances
to cold working, the weld shall be 100 % radiographically
specified in Table 3, except that for welded pipe the weld area
inspected in accordance with the requirements of ASME Boiler
shall not be limited by the “Over” tolerance. The wall thickness
and Pressure Vessel Code, Section VIII, Division 1, latest
and outside diameter for inspection for compliance with this
revision, Paragraph UW-51.
requirement for pipe ordered by NPS and schedule number is
6.1.5 Welded pipe and HCW pipe of NPS 14 and smaller
shown in Table X1.1.
shall have a single longitudinal weld. Welded pipe and HCW
pipe of a size larger than NPS 14 shall have a single
10. Tensile Requirements
longitudinal weld or shall be produced by forming and welding
10.1 The tensile properties of the material shall conform to
two longitudinal sections of flat stock when approved by the
the requirements prescribed in Table 4.
purchaser. All weld tests, examinations, inspections, or treat-
ments shall be performed on each weld seam.
11. Mechanical Tests, Grain Size Determinations, and
6.1.6 At the option of the manufacturer, pipe shall be either
Weld Decay Tests Required
hot finished or cold finished.
6.1.7 The pipe shall be free of scale and contaminating
11.1 Mechanical Testing Lot Definition—The term lot for
exogenous iron particles. Pickling, blasting, or surface finish- mechanical tests shall be as follows:
ing is not mandatory when pipe is bright annealed. The
11.1.1 Where the final heat treated condition is obtained,
purchaser is permitted to require that a passivating treatment be
consistent with the requirements of 6.2, in a continuous furnace
applied to the finished pipe.
or by quenching after hot forming, the term lot for mechanical
tests shall apply to all pipes of the same specified outside
diameter and specified wall thickness (or schedule) of the same
Available from American Welding Society (AWS), 550 NW LeJeune Rd.,
heat, heat treated in the same furnace at the same temperature,
Miami, FL 33126, http://www.aws.org.
time at heat, and furnace speed in the same production run, or
Available from Society of Automotive Engineers (SAE), 400 Commonwealth
Dr., Warrendale, PA 15096-0001, http://www.sae.org. all pipes of the same specified outside diameter and specified
A312/A312M − 24
TABLE 1 Chemical Requirements
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
TP201 S20100 0.15 5.5– 0.060 0.030 1.00 16.0– 3.5– . . . . . . . . . . . . 0.25 . . . . . . . . . . . . . . .
7.5 18.0 5.5
TP201LN S20153 0.03 6.4– 0.045 0.015 0.75 16.0– 4.0– . . . . . . . . . . . . 0.10– . . . 1.00 . . . . . . . . .
7.5 17.5 5.0 0.25
. . . S20400 0.030 7.0– 0.045 0.030 1.00 15.0– 1.50– . . . . . . . . . . . . 0.15– . . . . . . . . . . . . . . .
9.0 17.0 3.00 0.30
TPXM-19 S20910 0.06 4.0– 0.045 0.030 1.00 20.5– 11.5– 1.50– . . . 0.10– . . . 0.20– 0.10– . . . . . .
6.0 23.5 13.5 3.00 0.30 0.40 0.30
TPXM-10 S21900 0.08 8.0– 0.045 0.030 1.00 19.0– 5.5– . . . . . . . . . . . . 0.15– . . . . . . . . .
10.0 21.5 7.5 0.40
TPXM-11 S21904 0.04 8.0– 0.045 0.030 1.00 19.0– 5.5– . . . . . . . . . . . . 0.15– . . . . . . . . .
10.0 21.5 7.5 0.40
TPXM-29 S24000 0.08 11.5– 0.060 0.030 1.00 17.0– 2.3– . . . . . . . . . . . . 0.20– . . . . . . . . .
14.5 19.0 3.7 0.40
TP304 S30400 0.08 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . . . . . . . . . . . . .
20.0 11.0
D
TP304L S30403 0.035 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . . . . . . . . . . . . .
20.0 13.0
TP304H S30409 0.04– 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . . . . . . . . . . . . .
0.10 20.0 11.0
. . . S30415 0.04– 0.80 0.045 0.030 1.00– 18.0– 9.0– . . . . . . . . . . . . 0.12– . . . . . . 0.03–
0.06 2.00 19.0 10.0 0.18 0.08
. . . S30416 0.030 2.00 0.045 0.015 0.80– 17.5– 9.0– 0.40– . . . . . . . . . 0.10 . . . . . . . . .
2.00 19.5 11.0 0.80
TP304N S30451 0.08 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . 0.10– . . . . . . . . .
20.0 11.0 0.16
TP304LN S30453 0.035 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . 0.10– . . . . . . . . .
20.0 12.0 0.16
. . . S30600 0.018 2.00 0.02 0.02 3.7– 17.0– 14.0– 0.20 . . . . . . . . . . . . . . . 0.50 . . .
4.3 18.5 15.5 max
. . . S30601 0.015 0.50– 0.030 0.013 5.0– 17.0– 17.0– 0.20 . . . . . . . . . 0.05 . . . 0.35 . . . . . . . . . . . .
0.80 5.6 18.0 18.0
. . . S30615 0.16– 2.00 0.030 0.03 3.2– 17.0– 13.5– . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.80–
0.24 4.0 19.5 16.0 1.50
. . . S30815 0.05– 0.80 0.040 0.030 1.40– 20.0– 10.0– . . . . . . . . . . . . 0.14– . . . . . . 0.03–
0.10 2.00 22.0 12.0 0.20 0.08
TP309S S30908 0.08 2.00 0.045 0.030 1.00 22.0– 12.0– 0.75 . . . . . . . . . . . . . . . . . .
24.0 15.0
TP309H S30909 0.04– 2.00 0.045 0.030 1.00 22.0– 12.0– . . . . . . . . . . . . . . . . . . . . .
0.10 24.0 15.0
A312/A312M − 24
TABLE 1 Continued
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
TP309Cb S30940 0.08 2.00 0.045 0.030 1.00 22.0– 12.0– 0.75 . . . 10 × C . . . . . . . . . . . .
24.0 16.0 min,
1.10 max
TP309HCb S30941 0.04– 2.00 0.045 0.030 1.00 22.0– 12.0– 0.75 . . . 10 × C . . . . . . . . .
0.10 24.0 16.0 min,
1.10 max
S31002 0.015 2.00 0.020 0.015 0.15 24.0– 19.0– 0.10 . . . . . . . . . 0.10 . . .
26.0 22.0
TP310S S31008 0.08 2.00 0.045 0.030 1.00 24.0– 19.0– 0.75 . . . . . . . . . . . . . . . . . .
26.0 22.0
TP310H S31009 0.04– 2.00 0.045 0.030 1.00 24.0– 19.0– . . . . . . . . . . . . . . . . . . . . .
0.10 26.0 22.0
S31035 0.04– 0.60 0.025 0.015 0.40 21.5– 23.5– 0.40– 0.20– 2.5– 0.002– W 3.0–
0.10 23.5 26.5 0.60 0.30 3.5 0.008 4.0
Co 1.0–
2.0
TP310Cb S31040 0.08 2.00 0.045 0.030 1.00 24.0– 19.0– 0.75 . . . 10 × C . . . . . . . . . . . .
26.0 22.0 min,
1.10 max
TP310HCb S31041 0.04– 2.00 0.045 0.030 1.00 24.0– 19.0– 0.75 . . . 10 × C . . . . . . . . .
0.10 26.0 22.0 min,
1.10 max
. . . S31050 0.025 2.00 0.020 0.015 0.4 24.0– 20.5– 1.6– . . . . . . . . . 0.09– . . . . . . . . .
26.0 23.5 2.6 0.15
. . . S31254 0.020 1.00 0.030 0.010 0.80 19.5– 17.5– 6.0– . . . . . . . . . 0.18– . . . 0.50– . . .
20.5 18.5 6.5 0.25 1.00
. . . S31266 0.030 2.00– 0.035 0.020 1.00 23.0– 21.0– 5.2– 0.35– 1.00– W 1.50–
4.00 25.0 24.0 6.2 0.60 2.50 2.50
S31272 0.08– 1.5– 0.030 0.015 0.25– 14.0– 14.0– 1.00– 0.30– 0.004–
012 2.00 0.75 16.0 16.0 1.40 0.60 0.008
S31277 0.020 3.00 0.030 0.010 0.50 20.5– 26.0– 6.5– 0.30– 0.50–
23.0 28.0 8.0 0.40 1.50
TP316 S31600 0.08 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . . . . . . . . . . . . .
18.0 14.0 3.00
D
TP316L S31603 0.035 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . . . . . . . . . . . . .
18.0 14.0 3.00
TP316H S31609 0.04– 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . . . . . . . . . . . . .
0.10 18.0 14.0 3.00
TP316Ti S31635 0.08 2.00 0.045 0.030 0.75 16.0– 10.0– 2.00– 5× . . . . . . 0.10 . . . . . . . . . . . . . . .
18.0 14.0 3.00 (C+N)
–0.70
TP316N S31651 0.08 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– 0.10– . . . . . . . . .
18.0 14.0 3.00 0.16
TP316LN S31653 0.035 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . 0.10– . . . . . . . . .
18.0 14.0 3.00 0.16
A312/A312M − 24
TABLE 1 Continued
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
. . . S31655 0.030 2.00 0.045 0.015 1.00 19.5– 8.0– 0.50– . . . . . . . . . 0.14– . . . 1.00 . . . . . . . . . . . .
21.5 9.5 1.50 0.25
TP317 S31700 0.08 2.00 0.045 0.030 1.00 18.0– 11.0– 3.0– . . . . . . . . . . . . . . . . . . . . .
20.0 15.0 4.0
TP317L S31703 0.035 2.00 0.045 0.030 1.00 18.0– 11.0– 3.0– . . . . . . . . . . . . . . . . . . . . .
20.0 15.0 4.0
E
. . . S31725 0.03 2.00 0.040 0.030 1.00 18.0– 13.5– 4.0– . . . . . . . . . 0.10 . . . 0.75 . . .
20.0 17.5 5.0
E
. . . S31726 0.03 2.00 0.040 0.030 1.00 17.0– 13.5– 4.0– . . . . . . . . . 0.10– . . . 0.75 . . .
20.0 17.5 5.0 0.20
. . . S31727 0.03 1.00 0.030 0.030 1.00 17.5– 14.5– 3.8– . . . . . . . . . 0.15– . . . 2.8– . . . . . . . . .
19.0 16.5 4.5 0.21 4.0
. . . S31730 0.030 2.00 0.040 0.010 1.00 17.0– 15.0– 3.0– . . . . . . . . . 0.045 . . . 4.0– . . . . . . . . . . . .
19.0 16.5 4.0 5.0
. . . S31740 0.005– 2.00 0.045 0.030 1.00 17.0– 11.0– 3.0–4.5 . . . 0.20– . . . 0.06–0.15 . . . . . . . . . . . . . . . . . .
N N
0.020 19.0 15.0 0.50
. . . S32053 0.03 1.00 0.030 0.010 1.00 22.0– 24.0– 5.0– . . . . . . . . . 0.17– . . . . . . . . . . . . . . .
24.0 26.0 6.0 0.22
F
TP321 S32100 0.08 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . . . . 0.10 . . . . . . . . .
19.0 12.0
TP321H S32109 0.04– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . 4(C+N) . . . . . . 0.10 . . . . . . . . .
0.10 19.0 12.0 min;
0.70
max
. . . S32615 0.07 2.00 0.045 0.030 4.8– 16.5– 19.0– 0.30– . . . . . . . . . . . . . . . 1.50– . . .
6.0 19.5 22.0 1.50 2.50
. . . S32654 0.020 2.0– 0.030 0.005 0.50 24.0– 21.0– 7.0– . . . . . . . . . 0.45– . . . 0.30– . . .
4.0 25.0 23.0 8.0 0.55 0.60
. . . S33228 0.04– 1.00 0.020 0.015 0.30 26.0– 31.0– . . . . . . 0.60– . . . . . . . . . . . . 0.05– . . . 0.025
0.08 28.0 33.0 1.00 0.10
. . . S34565 0.03 5.0– 0.030 0.010 1.00 23.0– 16.0– 4.0– . . . 0.10 0.40– . . . . . . . . . . . .
7.0 25.0 18.0 5.0 0.60
G
TP347 S34700 0.08 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . . . . . . . . . . . . . . . .
19.0 13.0
H
TP347H S34709 0.04– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . . . . . . . . . . . . . . . .
0.10 19.0 13.0
TP347LN S34751 0.005– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . 0.20– . . . 0.06– . . . . . . . . . . . . . . .
I
0.020 19.0 13.0 0.50 0.10
S34752 0.005– 2.00 0.035 0.010 0.60 17.0– 10.0– 0.20– . . . 0.20– . . . 0.06– . . . 2.50– . . . 0.001– . . .
I
0.020 19.0 13.0 1.20 0.50 0.12 3.50 0.005
G
TP348 S34800 0.08 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . 0.10 . . . . . . . . . . . .
19.0 13.0
H
TP348H S34809 0.04– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . 0.10 . . . . . . . . . . . .
0.10 19.0 13.0
A312/A312M − 24
TABLE 1 Continued
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
. . . S35045 0.06– 1.50 . . . 0.015 1.00 25.0– 32.0– . . . 0.15– . . . . . . . . . . . . 0.75 . . . . . . 0.15–
0.10 29.0 37.0 0.60 0.60
. . . S35315 0.04– 2.00 0.040 0.030 1.20– 24.0– 34.0– . . . . . . . . . . . . 0.12– . . . . . . 0.03– . . . . . .
0.08 2.00 26.0 36.0 0.18 0.08
TPXM-15 S38100 0.08 2.00 0.030 0.030 1.50– 17.0– 17.5– . . . . . . . . . . . . . . . . . . . . . . . .
2.50 19.0 18.5
. . . S38815 0.030 2.00 0.040 0.020 5.5– 13.0– 15.0– 0.75– . . . . . . . . . . . . . . . 0.75– . . . . . . 0.30
6.5 15.0 17.0 1.50 1.50
. . . S35030 0.05– 1.50 0.030 0.015 0.5– 18.5– 22.5– . . . . . . 0.25– . . . 0.05– . . . 2.5– . . . . . . . . .
0.10 2.0 22.5 27.5 0.75 0.15 3.5
L L
Alloy 20 N08020 0.07 2.00 0.045 0.035 1.00 19.0– 32.0– 2.0– . . . . . . . . . 3.0– . . . . . . . . .
21.0 38.0 3.0 4.0
N08028 0.030 2.50 0.030 0.030 1.0 26.0– 30.0– 3.0– 0.60–
28.0 34.0 4.0 1.4
N08029 0.020 2.0 0.025 0.015 0.6 26.0– 30.0– 4.0– 0.6–
28.0 34.0 5.0 1.4
. . . N08367 0.030 2.00 0.040 0.030 1.00 20.0– 23.5– 6.0– . . . . . . . . . 0.18– . . . 0.75 . . . . . . . . .
22.0 25.5 7.0 0.25
J
800 N08800 0.10 1.50 0.045 0.015 1.00 19.0– 30.0– . . . . . . . . . . . . . . . . . . 0.75 . . . . . . 0.15– Fe
39.5 min.
23.0 35.0 0.60
J
800H N08810 0.05– 1.50 0.045 0.015 1.00 19.0– 30.0– . . . 0.15– . . . . . . . . . . . . 0.75 . . . . . . 0.15– Fe
39.5 min.
0.10 23.0 35.0 0.60 0.60
J
N08811 0.06– 1.50 0.045 0.015 1.00 19.0– 30.0– . . . 0.15– . . . . . . . . . . . . 0.75 . . . . . . 0.15– Fe
K K
39.5 min.
0.10 23.0 35.0 0.60 0.60
. . . N08904 0.020 2.00 0.040 0.030 1.00 19.0– 23.0– 4.0– . . . . . . . . . 0.10 . . . 1.00– . . . . . . . . .
23.0 28.0 5.0 2.00
. . . N08925 0.020 1.00 0.045 0.030 0.50 19.0– 24.0– 6.0– . . . . . . . . . 0.10– . . . 0.80– . . . . . . . . .
21.0 26.0 7.0 0.20 1.50
. . . N08926 0.020 2.00 0.030 0.010 0.50 19.0– 24.0– 6.0– . . . . . . . . . 0.15– . . . 0.50– . . . . . . . . .
21.0 26.0 7.0 0.25 1.50
A
New designation established in accordance with Practice E527 and SAE J1086.
B
Maximum, unless otherwise indicated. Where elipses (.) appear in this table, there is no requirement and analysis for the element need not be determined or reported.
C
The method of analysis for nitrogen shall be a matter of agreement between the purchaser and manufacturer.
D
For small diameter or thin walls or both, where many drawing passes are required, a carbon maximum of 0.040 % is necessary in grades TP304L and TP316L. Small outside diameter tubes are defined as those less
than 0.500 in. [12.7 mm] in outside diameter and light wall tubes as those less than 0.049 in. [1.20 mm] in average wall thickness (0.044 in. [1.10 mm] in minimum wall thickness).
E
For welded pipe, the phosphorus maximum shall be 0.045 %.
F
Ti 5 × (C+N) min, 0.70 max.
G
The niobium content shall be not less than ten times the carbon content and not more than 1.00 %.
H
The niobium content shall be not less than eight times the carbon content and not more than 1.0 %.
I
Grade S34751 and Grade S34752 shall have a niobium content of not less than 15 times the carbon content.
J
Iron shall be determined arithmetically by difference of 100 minus the sum of the other specified elements.
K
Al + Ti shall be 0.85 % min; 1.20 % max.
L
Niobium (Nb) + Tantalum = 8 × Carbon min, 1.00 max.
M
The terms Niobium (Nb) and Columbium (Cb) are alternative names for the same element.
N
S31740 shall have a niobium (columbium) content of not less than 15 times the carbon content.

A312/A312M − 24
TABLE 2 Annealing Requirements TABLE 3 Permitted Variations in Wall Thickness
A
Grade or UNS Designation Heat Treating Cooling/Testing Tolerance, % from Nominal
B
Temperature Requirements NPS Designator Over Under
1 1
C ⁄8 to 2 ⁄2 incl., all t/D
All grades not individually listed 1900 °F [1040 °C]
20.0 12.5
ratios
below:
3 to 18 incl., t/D up to
TP321H, TP347H, TP348H
22.5 12.5
5 % incl.
D
Cold finished 2000 °F [1100 °C]
D 3 to 18 incl., t/D > 5 % 15.0 12.5
Hot finished 1925 °F [1050 °C]
20 and larger, welded,
TP304H, TP316H
17.5 12.5
D all t/D ratios
Cold finished 1900 °F [1040 °C]
D 20 and larger,
Hot finished 1900 °F [1040 °C]
seamless, t/D up to 22.5 12.5
D
TP309H, TP309HCb, TP310H, 1900 °F [1040 °C]
5 % incl.
TP310HCb
20 and larger,
D
S30600 2010–2140 °F
15.0 12.5
seamless, t/D > 5 %
[1100–1170 °C]
D
S30601 2010–2140 °F
where:
[1100–1170 °C]
D
S30815, S31272 1920 °F [1050 °C]
t = Nominal Wall Thickness
D
S31035 2160–2280 °F
D = Ordered Outside Diameter
[1180–1250 °C]
D
S31254, S32654 2100 °F [1150 °C]
D
S31266 2100 °F [1150 °C]
D
S31277 2050 °F [1120 °C]
D
S31727, S32053 1975–2155 °F
controlled within a 50 °F [30 °C] or lesser range, the term lot
[1080–1180 °C]
shall apply to the larger of: (a) each 200 ft [60 m] or fraction
D
S33228 2050–2160 °F
[1120–1180 °C] thereof and (b) those pipes heat treated in the same furnace
D
S34565 2050–2140 °F
batch charge for pipes of the same specified outside diameter
[1120–1170 °C]
D and specified wall thickness (or schedule) that are produced
S34752 1940–2138 °F
[1060–1170 °C] from the same heat of steel and are subjected to the same
D
S35315 2010 °F [1100 °C]
finishing temperature within the same production run.
D
S38815 1950 °F [1065 °C]
D
N08367 2025 °F [1110 °C]
11.2 Transverse or Longitudinal Tension Test—One tension
D
N08020 1700–1850 °F
test shall be made on a specimen for lots of not more than 100
[925–1010 °C]
D
pipes. Tension tests shall be made on specimens from two tubes
N08028 2000 °F [1100 °C]
D
N08029 2000 °F [1100 °C]
for lots of more than 100 pipes.
D
N08810 2050 °F [1120 °C]
D
N08811 2100 °F [1150 °C] 11.3 Flattening Test—For material heat treated in a continu-
D
N08904 2000 °F [1100 °C]
ous furnace, by quenching after hot forming or in a batch-type
D
N08925, N08926 2010–2100 °F
furnace equipped with recording pyrometers and automatically
[1100–1150 °C]
controlled within a 50 °F [30 °C] or lesser range, flattening
A
New designation established in accordance with Practice E527 and SAE J1086.
B
tests shall be made on a sufficient number of pipe to constitute
Minimum, unless otherwise stated.
C
Quenched in water or rapidly cooled by other means, at a rate sufficient to
5 % of the lot, but in no case less than 2 lengths of pipe. For
prevent re-precipitation of carbides, as demonstrable by the capability of pipes,
material heat treated in a batch-type furnace not equipped with
heat treated by either separate solution annealing or by direct quenching, of
recording pyrometers and automatically controlled within a 50
passing Practices A262, Practice E. The manufacturer is not required to run the
test unless it is specified on the purchase order (see Supplementary Requirement
°F [30 °C] or lesser range, flattening tests shall be made on 5 %
S7). Note that Practices A262 requires the test to be performed on sensitized
of the pipe from each heat treated lot.
specimens in the low-carbon and stabilize
...

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: A312/A312M − 22a A312/A312M − 24 Used in USDOE-NE standards
Standard Specification for
Seamless, Welded, and Heavily Cold Worked Austenitic
Stainless Steel Pipes
This standard is issued under the fixed designation A312/A312M; 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 seamless, straight-seam welded, and heavily cold worked welded austenitic stainless steel pipe
intended for high-temperature and general corrosive service.
1.2 Grades TP304H, TP309H, TP309HCb, TP310H, TP310HCb, TP316H, TP321H, TP347H, and TP348H are modifications of
Grades TP304, TP309Cb, TP309S, TP310Cb, TP310S, TP316, TP321, TP347, and TP348, and are intended for service at
temperatures where creep and stress rupture properties are important.
1.3 Optional supplementary requirements are provided for pipe where a greater degree of testing is desired. These supplementary
requirements call for additional tests to be made and, when desired, it is permitted to specify in the order one or more of these
supplementary requirements.
1.4 Table X1.1 lists the standardized dimensions of welded and seamless stainless steel pipe as shown in ASME B36.19. These
dimensions are also applicable to heavily cold worked pipe. Pipe having other dimensions is permitted to be ordered and furnished
provided such pipe complies with all other requirements of this specification.
1.5 Grades TP321 and TP321H have lower strength requirements for pipe manufactured by the seamless process in nominal wall
thicknesses greater than ⁄8 in. [9.5 mm].
1.6 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. The
inch-pound units shall apply unless the “M” designation of this specification is specified in the order.
NOTE 1—The dimensionless designator NPS (nominal pipe size) has been substituted in this standard for such traditional terms as “nominal diameter,”
“size,” and “nominal size.”
1.7 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.
This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.10
on Stainless and Alloy Steel Tubular Products.
Current edition approved Nov. 1, 2022March 1, 2024. Published December 2022March 2024. Originally approved in 1948. Last previous edition approved in 2022 as
A312/A312M – 22.A312/A312M – 22a. DOI: 10.1520/A0312_A0312M-22A.10.1520/A0312_A0312M-24.
For ASME Boiler and Pressure Vessel Code applications see related Specification SA-312 in Section II of that Code.
*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
A312/A312M − 24
2. Referenced Documents
2.1 ASTM Standards:
A262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels
A370 Test Methods and Definitions for Mechanical Testing of Steel Products
A941 Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
A999/A999M Specification for General Requirements for Alloy and Stainless Steel Pipe
A1016/A1016M Specification for General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel
Tubes
E112 Test Methods for Determining Average Grain Size
E381 Method of Macroetch Testing Steel Bars, Billets, Blooms, and Forgings
E527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)
2.2 ASME Standards:
B1.20.1 Pipe Threads, General Purpose
B36.10M Welded and Seamless Wrought Steel Pipe
B36.19 Stainless Steel Pipe
ASME Boiler and Pressure Vessel Code : Section VIII
2.3 AWS Standard:
A5.9 Corrosion-Resisting Chromium and Chromium-Nickel Steel Welding Rods and Electrodes
2.4 Other Standard:
SAE J1086 Practice for Numbering Metals and Alloys (UNS)
3. Terminology
3.1 Definitions:
3.1.1 The definitions in Specification A999/A999M and Terminology A941 are applicable to this specification.
4. Ordering Information
4.1 Orders for material to this specification shall conform to the requirements of the current edition of Specification A999/A999M.
5. General Requirements
5.1 Material furnished under this specification shall conform to the applicable requirements of the current edition of Specification
A999/A999M unless otherwise provided herein.
6. Materials and Manufacture
6.1 Manufacture:
6.1.1 The pipe shall be manufactured by one of the following processes:
6.1.2 Seamless (SML) pipe shall be made by a process that does not involve welding at any stage of production.
6.1.3 Welded (WLD) pipe shall be made using an automatic welding process with no addition of filler metal during the welding
process.
6.1.4 Heavily cold-worked (HCW) pipe shall be made by applying cold working of not less than 35 % reduction in thickness of
both wall and weld to a welded pipe prior to the final anneal. No filler shall be used in making the weld. Prior to cold working,
the weld shall be 100 % radiographically inspected in accordance with the requirements of ASME Boiler and Pressure Vessel Code,
Section VIII, Division 1, latest revision, Paragraph UW-51.
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.
Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
www.asme.org.
Available from American Welding Society (AWS), 550 NW LeJeune Rd., Miami, FL 33126, http://www.aws.org.
Available from Society of Automotive Engineers (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http://www.sae.org.
A312/A312M − 24
TABLE 1 Chemical Requirements
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A
Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
TP201 S20100 0.15 5.5– 0.060 0.030 1.00 16.0– 3.5– . . . . . . . . . . . . 0.25 . . . . . . . . . . . . . . .
7.5 18.0 5.5
TP201LN S20153 0.03 6.4– 0.045 0.015 0.75 16.0– 4.0– . . . . . . . . . . . . 0.10– . . . 1.00 . . . . . . . . .
7.5 17.5 5.0 0.25
. . . S20400 0.030 7.0– 0.045 0.030 1.00 15.0– 1.50– . . . . . . . . . . . . 0.15– . . . . . . . . . . . . . . .
9.0 17.0 3.00 0.30
TPXM-19 S20910 0.06 4.0– 0.045 0.030 1.00 20.5– 11.5– 1.50– . . . 0.10– . . . 0.20– 0.10– . . . . . .
6.0 23.5 13.5 3.00 0.30 0.40 0.30
TPXM-10 S21900 0.08 8.0– 0.045 0.030 1.00 19.0– 5.5– . . . . . . . . . . . . 0.15– . . . . . . . . .
10.0 21.5 7.5 0.40
TPXM-11 S21904 0.04 8.0– 0.045 0.030 1.00 19.0– 5.5– . . . . . . . . . . . . 0.15– . . . . . . . . .
10.0 21.5 7.5 0.40
TPXM-29 S24000 0.08 11.5– 0.060 0.030 1.00 17.0– 2.3– . . . . . . . . . . . . 0.20– . . . . . . . . .
14.5 19.0 3.7 0.40
TP304 S30400 0.08 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . . . . . . . . . . . . .
20.0 11.0
D
TP304L S30403 0.035 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . . . . . . . . . . . . .
20.0 13.0
TP304H S30409 0.04– 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . . . . . . . . . . . . .
0.10 20.0 11.0
. . . S30415 0.04– 0.80 0.045 0.030 1.00– 18.0– 9.0– . . . . . . . . . . . . 0.12– . . . . . . 0.03–
0.06 2.00 19.0 10.0 0.18 0.08
. . . S30416 0.030 2.00 0.045 0.015 0.80– 17.5– 9.0– 0.40– . . . . . . . . . 0.10 . . . . . . . . .
2.00 19.5 11.0 0.80
TP304N S30451 0.08 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . 0.10– . . . . . . . . .
20.0 11.0 0.16
TP304LN S30453 0.035 2.00 0.045 0.030 1.00 18.0– 8.0– . . . . . . . . . . . . 0.10– . . . . . . . . .
20.0 12.0 0.16
. . . S30600 0.018 2.00 0.02 0.02 3.7– 17.0– 14.0– 0.20 . . . . . . . . . . . . . . . 0.50 . . .
4.3 18.5 15.5 max
. . . S30601 0.015 0.50– 0.030 0.013 5.0– 17.0– 17.0– 0.20 . . . . . . . . . 0.05 . . . 0.35 . . . . . . . . . . . .
0.80 5.6 18.0 18.0
. . . S30615 0.16– 2.00 0.030 0.03 3.2– 17.0– 13.5– . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.80–
0.24 4.0 19.5 16.0 1.50
. . . S30815 0.05– 0.80 0.040 0.030 1.40– 20.0– 10.0– . . . . . . . . . . . . 0.14– . . . . . . 0.03–
0.10 2.00 22.0 12.0 0.20 0.08
TP309S S30908 0.08 2.00 0.045 0.030 1.00 22.0– 12.0– 0.75 . . . . . . . . . . . . . . . . . .
24.0 15.0
TP309H S30909 0.04– 2.00 0.045 0.030 1.00 22.0– 12.0– . . . . . . . . . . . . . . . . . . . . .
0.10 24.0 15.0
A312/A312M − 24
TABLE 1 Continued
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
TP309Cb S30940 0.08 2.00 0.045 0.030 1.00 22.0– 12.0– 0.75 . . . 10 × C . . . . . . . . . . . .
24.0 16.0 min,
1.10 max
TP309HCb S30941 0.04– 2.00 0.045 0.030 1.00 22.0– 12.0– 0.75 . . . 10 × C . . . . . . . . .
0.10 24.0 16.0 min,
1.10 max
S31002 0.015 2.00 0.020 0.015 0.15 24.0– 19.0– 0.10 . . . . . . . . . 0.10 . . .
26.0 22.0
TP310S S31008 0.08 2.00 0.045 0.030 1.00 24.0– 19.0– 0.75 . . . . . . . . . . . . . . . . . .
26.0 22.0
TP310H S31009 0.04– 2.00 0.045 0.030 1.00 24.0– 19.0– . . . . . . . . . . . . . . . . . . . . .
0.10 26.0 22.0
S31035 0.04– 0.60 0.025 0.015 0.40 21.5– 23.5– 0.40– 0.20– 2.5– 0.002– W 3.0–
0.10 23.5 26.5 0.60 0.30 3.5 0.008 4.0
Co 1.0–
2.0
TP310Cb S31040 0.08 2.00 0.045 0.030 1.00 24.0– 19.0– 0.75 . . . 10 × C . . . . . . . . . . . .
26.0 22.0 min,
1.10 max
TP310HCb S31041 0.04– 2.00 0.045 0.030 1.00 24.0– 19.0– 0.75 . . . 10 × C . . . . . . . . .
0.10 26.0 22.0 min,
1.10 max
. . . S31050 0.025 2.00 0.020 0.015 0.4 24.0– 20.5– 1.6– . . . . . . . . . 0.09– . . . . . . . . .
26.0 23.5 2.6 0.15
. . . S31254 0.020 1.00 0.030 0.010 0.80 19.5– 17.5– 6.0– . . . . . . . . . 0.18– . . . 0.50– . . .
20.5 18.5 6.5 0.25 1.00
. . . S31266 0.030 2.00– 0.035 0.020 1.00 23.0– 21.0– 5.2– 0.35– 1.00– W 1.50–
4.00 25.0 24.0 6.2 0.60 2.50 2.50
S31272 0.08– 1.5– 0.030 0.015 0.25– 14.0– 14.0– 1.00– 0.30– 0.004–
012 2.00 0.75 16.0 16.0 1.40 0.60 0.008
S31277 0.020 3.00 0.030 0.010 0.50 20.5– 26.0– 6.5– 0.30– 0.50–
23.0 28.0 8.0 0.40 1.50
TP316 S31600 0.08 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . . . . . . . . . . . . .
18.0 14.0 3.00
D
TP316L S31603 0.035 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . . . . . . . . . . . . .
18.0 14.0 3.00
TP316H S31609 0.04– 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . . . . . . . . . . . . .
0.10 18.0 14.0 3.00
TP316Ti S31635 0.08 2.00 0.045 0.030 0.75 16.0– 10.0– 2.00– 5× . . . . . . 0.10 . . . . . . . . . . . . . . .
18.0 14.0 3.00 (C+N)
–0.70
TP316N S31651 0.08 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– 0.10– . . . . . . . . .
18.0 14.0 3.00 0.16
TP316LN S31653 0.035 2.00 0.045 0.030 1.00 16.0– 10.0– 2.00– . . . . . . . . . 0.10– . . . . . . . . .
18.0 14.0 3.00 0.16
A312/A312M − 24
TABLE 1 Continued
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
. . . S31655 0.030 2.00 0.045 0.015 1.00 19.5– 8.0– 0.50– . . . . . . . . . 0.14– . . . 1.00 . . . . . . . . . . . .
21.5 9.5 1.50 0.25
TP317 S31700 0.08 2.00 0.045 0.030 1.00 18.0– 11.0– 3.0– . . . . . . . . . . . . . . . . . . . . .
20.0 15.0 4.0
TP317L S31703 0.035 2.00 0.045 0.030 1.00 18.0– 11.0– 3.0– . . . . . . . . . . . . . . . . . . . . .
20.0 15.0 4.0
E
. . . S31725 0.03 2.00 0.040 0.030 1.00 18.0– 13.5– 4.0– . . . . . . . . . 0.10 . . . 0.75 . . .
20.0 17.5 5.0
E
. . . S31726 0.03 2.00 0.040 0.030 1.00 17.0– 13.5– 4.0– . . . . . . . . . 0.10– . . . 0.75 . . .
20.0 17.5 5.0 0.20
. . . S31727 0.03 1.00 0.030 0.030 1.00 17.5– 14.5– 3.8– . . . . . . . . . 0.15– . . . 2.8– . . . . . . . . .
19.0 16.5 4.5 0.21 4.0
. . . S31730 0.030 2.00 0.040 0.010 1.00 17.0– 15.0– 3.0– . . . . . . . . . 0.045 . . . 4.0– . . . . . . . . . . . .
19.0 16.5 4.0 5.0
. . . S31740 0.005– 2.00 0.045 0.030 1.00 17.0– 11.0– 3.0–4.5 . . . 0.20– . . . 0.06–0.15 . . . . . . . . . . . . . . . . . .
N N
0.020 19.0 15.0 0.50
. . . S32053 0.03 1.00 0.030 0.010 1.00 22.0– 24.0– 5.0– . . . . . . . . . 0.17– . . . . . . . . . . . . . . .
24.0 26.0 6.0 0.22
F
TP321 S32100 0.08 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . . . . 0.10 . . . . . . . . .
19.0 12.0
TP321H S32109 0.04– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . 4(C+N) . . . . . . 0.10 . . . . . . . . .
0.10 19.0 12.0 min;
0.70
max
. . . S32615 0.07 2.00 0.045 0.030 4.8– 16.5– 19.0– 0.30– . . . . . . . . . . . . . . . 1.50– . . .
6.0 19.5 22.0 1.50 2.50
. . . S32654 0.020 2.0– 0.030 0.005 0.50 24.0– 21.0– 7.0– . . . . . . . . . 0.45– . . . 0.30– . . .
4.0 25.0 23.0 8.0 0.55 0.60
. . . S33228 0.04– 1.00 0.020 0.015 0.30 26.0– 31.0– . . . . . . 0.60– . . . . . . . . . . . . 0.05– . . . 0.025
0.08 28.0 33.0 1.00 0.10
. . . S34565 0.03 5.0– 0.030 0.010 1.00 23.0– 16.0– 4.0– . . . 0.10 0.40– . . . . . . . . . . . .
7.0 25.0 18.0 5.0 0.60
G
TP347 S34700 0.08 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . . . . . . . . . . . . . . . .
19.0 13.0
H
TP347H S34709 0.04– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . . . . . . . . . . . . . . . .
0.10 19.0 13.0
TP347LN S34751 0.005– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . 0.20– . . . 0.06– . . . . . . . . . . . . . . .
I
0.020 19.0 13.0 0.50 0.10
S34752 0.005– 2.00 0.035 0.010 0.60 17.0– 10.0– 0.20– . . . 0.20– . . . 0.06– . . . 2.50– . . . 0.001– . . .
I
0.020 19.0 13.0 1.20 0.50 0.12 3.50 0.005
G
TP348 S34800 0.08 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . 0.10 . . . . . . . . . . . .
19.0 13.0
H
TP348H S34809 0.04– 2.00 0.045 0.030 1.00 17.0– 9.0– . . . . . . 0.10 . . . . . . . . . . . .
0.10 19.0 13.0
A312/A312M − 24
TABLE 1 Continued
B
Composition, %
UNS
Tanta-
Grade Desig-
Manga- Phos- Chrom- Molyb- Tita- Nitro- Vana- Alum-
M
A Carbon Sulfur Silicon Nickel Niobium lum, Copper Cerium Boron Other
C
nation
nese phorus ium denum nium gen dium inum
max
. . . S35045 0.06– 1.50 . . . 0.015 1.00 25.0– 32.0– . . . 0.15– . . . . . . . . . . . . 0.75 . . . . . . 0.15–
0.10 29.0 37.0 0.60 0.60
. . . S35315 0.04– 2.00 0.040 0.030 1.20– 24.0– 34.0– . . . . . . . . . . . . 0.12– . . . . . . 0.03– . . . . . .
0.08 2.00 26.0 36.0 0.18 0.08
TPXM-15 S38100 0.08 2.00 0.030 0.030 1.50– 17.0– 17.5– . . . . . . . . . . . . . . . . . . . . . . . .
2.50 19.0 18.5
. . . S38815 0.030 2.00 0.040 0.020 5.5– 13.0– 15.0– 0.75– . . . . . . . . . . . . . . . 0.75– . . . . . . 0.30
6.5 15.0 17.0 1.50 1.50
. . . S35030 0.05– 1.50 0.030 0.015 0.5– 18.5– 22.5– . . . . . . 0.25– . . . 0.05– . . . 2.5– . . . . . . . . .
0.10 2.0 22.5 27.5 0.75 0.15 3.5
L L
Alloy 20 N08020 0.07 2.00 0.045 0.035 1.00 19.0– 32.0– 2.0– . . . . . . . . . 3.0– . . . . . . . . .
21.0 38.0 3.0 4.0
N08028 0.030 2.50 0.030 0.030 1.0 26.0– 30.0– 3.0– 0.60–
28.0 34.0 4.0 1.4
N08029 0.020 2.0 0.025 0.015 0.6 26.0– 30.0– 4.0– 0.6–
28.0 34.0 5.0 1.4
. . . N08367 0.030 2.00 0.040 0.030 1.00 20.0– 23.5– 6.0– . . . . . . . . . 0.18– . . . 0.75 . . . . . . . . .
22.0 25.5 7.0 0.25
J
800 N08800 0.10 1.50 0.045 0.015 1.00 19.0– 30.0– . . . . . . . . . . . . . . . . . . 0.75 . . . . . . 0.15– Fe
39.5 min.
23.0 35.0 0.60
J
800H N08810 0.05– 1.50 0.045 0.015 1.00 19.0– 30.0– . . . 0.15– . . . . . . . . . . . . 0.75 . . . . . . 0.15– Fe
39.5 min.
0.10 23.0 35.0 0.60 0.60
J
N08811 0.06– 1.50 0.045 0.015 1.00 19.0– 30.0– . . . 0.15– . . . . . . . . . . . . 0.75 . . . . . . 0.15– Fe
K K
39.5 min.
0.10 23.0 35.0 0.60 0.60
. . . N08904 0.020 2.00 0.040 0.030 1.00 19.0– 23.0– 4.0– . . . . . . . . . 0.10 . . . 1.00– . . . . . . . . .
23.0 28.0 5.0 2.00
. . . N08925 0.020 1.00 0.045 0.030 0.50 19.0– 24.0– 6.0– . . . . . . . . . 0.10– . . . 0.80– . . . . . . . . .
21.0 26.0 7.0 0.20 1.50
. . . N08926 0.020 2.00 0.030 0.010 0.50 19.0– 24.0– 6.0– . . . . . . . . . 0.15– . . . 0.50– . . . . . . . . .
21.0 26.0 7.0 0.25 1.50
A
New designation established in accordance with Practice E527 and SAE J1086.
B
Maximum, unless otherwise indicated. Where elipses (.) appear in this table, there is no requirement and analysis for the element need not be determined or reported.
C
The method of analysis for nitrogen shall be a matter of agreement between the purchaser and manufacturer.
D
For small diameter or thin walls or both, where many drawing passes are required, a carbon maximum of 0.040 % is necessary in grades TP304L and TP316L. Small outside diameter tubes are defined as those less
than 0.500 in. [12.7 mm] in outside diameter and light wall tubes as those less than 0.049 in. [1.20 mm] in average wall thickness (0.044 in. [1.10 mm] in minimum wall thickness).
E
For welded pipe, the phosphorus maximum shall be 0.045 %.
F
Ti 5 × (C+N) min, 0.70 max.
G
The niobium content shall be not less than ten times the carbon content and not more than 1.00 %.
H
The niobium content shall be not less than eight times the carbon content and not more than 1.0 %.
I
Grade S34751 and Grade S34752 shall have a niobium content of not less than 15 times the carbon content.
J
Iron shall be determined arithmetically by difference of 100 minus the sum of the other specified elements.
K
Al + Ti shall be 0.85 % min; 1.20 % max.
L
Niobium (Nb) + Tantalum = 8 × Carbon min, 1.00 max.
M
The terms Niobium (Nb) and Columbium (Cb) are alternative names for the same element.
N
S31740 shall have a niobium (columbium) content of not less than 15 times the carbon content.

A312/A312M − 24
6.1.5 Welded pipe and HCW pipe of NPS 14 and smaller shall have a single longitudinal weld. Welded pipe and HCW pipe of
a size larger than NPS 14 shall have a single longitudinal weld or shall be produced by forming and welding two longitudinal
sections of flat stock when approved by the purchaser. All weld tests, examinations, inspections, or treatments shall be performed
on each weld seam.
6.1.6 At the option of the manufacturer, pipe shall be either hot finished or cold finished.
6.1.7 The pipe shall be free of scale and contaminating exogenous iron particles. Pickling, blasting, or surface finishing is not
mandatory when pipe is bright annealed. The purchaser is permitted to require that a passivating treatment be applied to the
finished pipe.
6.2 Heat Treatment—All pipe shall be furnished in the heat-treated condition in accordance with the requirements of Table 2.
TABLE 2 Annealing Requirements
A
Grade or UNS Designation Heat Treating Cooling/Testing
B
Temperature Requirements
C
All grades not individually listed 1900 °F [1040 °C]
below:
TP321H, TP347H, TP348H
D
Cold finished 2000 °F [1100 °C]
D
Hot finished 1925 °F [1050 °C]
TP304H, TP316H
D
Cold finished 1900 °F [1040 °C]
D
Hot finished 1900 °F [1040 °C]
D
TP309H, TP309HCb, TP310H, 1900 °F [1040 °C]
TP310HCb
D
S30600 2010–2140 °F
[1100–1170 °C]
D
S30601 2010–2140 °F
[1100–1170 °C]
D
S30815, S31272 1920 °F [1050 °C]
D
S31035 2160–2280 °F
[1180–1250 °C]
D
S31254, S32654 2100 °F [1150 °C]
D
S31266 2100 °F [1150 °C]
D
S31277 2050 °F [1120 °C]
D
S31727, S32053 1975–2155 °F
[1080–1180 °C]
D
S33228 2050–2160 °F
[1120–1180 °C]
D
S34565 2050–2140 °F
[1120–1170 °C]
D
S34752 1940–2138 °F
[1060–1170 °C]
D
S35315 2010 °F [1100 °C]
D
S38815 1950 °F [1065 °C]
D
N08367 2025 °F [1110 °C]
D
N08020 1700–1850 °F
[925–1010 °C]
D
N08028 2000 °F [1100 °C]
D
N08029 2000 °F [1100 °C]
D
N08810 2050 °F [1120 °C]
D
N08811 2100 °F [1150 °C]
D
N08904 2000 °F [1100 °C]
D
N08925, N08926 2010–2100 °F
[1100–1150 °C]
A
New designation established in accordance with Practice E527 and SAE J1086.
B
Minimum, unless otherwise stated.
C
Quenched in water or rapidly cooled by other means, at a rate sufficient to
prevent re-precipitation of carbides, as demonstrable by the capability of pipes,
heat treated by either separate solution annealing or by direct quenching, of
passing Practices A262, Practice E. The manufacturer is not required to run the
test unless it is specified on the purchase order (see Supplementary Requirement
S7). Note that Practices A262 requires the test to be performed on sensitized
specimens in the low-carbon and stabilized types and on specimens representa-
tive of the as-shipped condition for other types. In the case of low-carbon types
containing 3 % or more molybdenum, the applicability of the sensitizing treatment
prior to testing shall be a matter for negotiation between the seller and the
purchaser.
D
Quenched in water or rapidly cooled by other means.
A312/A312M − 24
Alternatively, for seamless pipe, immediately following hot forming while the temperature of the pipes is not less than the
minimum solution treatment temperature specified in Table 2, pipes shall be individually quenched in water or rapidly cooled by
other means (direct quenched).
7. Chemical Composition
7.1 The steel shall conform to the requirements as to chemical composition prescribed in Table 1.
8. Product Analysis
8.1 At the request of the purchaser, an analysis of one billet or one length of flat-rolled stock from each heat, or two pipes from
each lot shall be made by the manufacturer. A lot of pipe shall consist of the following number of lengths of the same size and
wall thickness from any one heat of steel:
NPS Designator Lengths of Pipe in Lot
Under 2 400 or fraction thereof
2 to 5 200 or fraction thereof
6 and over 100 or fraction thereof
8.2 The results of these analyses shall be reported to the purchaser or the purchaser’s representative, and shall conform to the
requirements specified in Section 7.
8.3 If the analysis of one of the tests specified in 8.1 does not conform to the requirements specified in Section 7, an analysis of
each billet or pipe from the same heat or lot may be made, and all billets or pipe conforming to the requirements shall be accepted.
9. Permitted Variations in Wall Thickness
9.1 In addition to the implicit limitation of wall thickness for seamless pipe imposed by the limitation on weight in Specification
A999/A999M, the wall thickness for seamless and welded pipe at any point shall be within the tolerances specified in Table 3,
except that for welded pipe the weld area shall not be limited by the “Over” tolerance. The wall thickness and outside diameter
for inspection for compliance with this requirement for pipe ordered by NPS and schedule number is shown in Table X1.1.
10. Tensile Requirements
10.1 The tensile properties of the material shall conform to the requirements prescribed in Table 4.
11. Mechanical Tests, Grain Size Determinations, and Weld Decay Tests Required
11.1 Mechanical Testing Lot Definition—The term lot for mechanical tests shall be as follows:
TABLE 3 Permitted Variations in Wall Thickness
Tolerance, % from Nominal
NPS Designator Over Under
1 1
⁄8 to 2 ⁄2 incl., all t/D
20.0 12.5
ratios
3 to 18 incl., t/D up to
22.5 12.5
5 % incl.
3 to 18 incl., t/D > 5 % 15.0 12.5
20 and larger, welded,
17.5 12.5
all t/D ratios
20 and larger,
seamless, t/D up to 22.5 12.5
5 % incl.
20 and larger,
15.0 12.5
seamless, t/D > 5 %
where:
t = Nominal Wall Thickness
D = Ordered Outside Diameter
A312/A312M − 24
TABLE 4 Tensile Requirements
Grade UNS Tensile Yield
Designation Strength, min Strength, min
ksi [MPa] ksi [MPa]
TP201 S20100 75 [515] 38 [260]
TP201LN S20153 95 [655] 45 [310]
. . . S20400 95 [635] 48 [330]
TPXM-19 S20910 100 [690] 55 [380]
TPXM-10 S21900 90 [620] 50 [345]
TPXM-11 S21904 90 [620] 50 [345]
TPXM-29 S24000 100 [690] 55 [380]
TP304 S30400 75 [515] 30 [205]
TP304L S30403 70 [485] 25 [170]
TP304H S30409 75 [515] 30 [205]
. . . S30415 87 [600] 42 [290]
. . . S30416 73 [500] 32 [220]
TP304N S30451 80 [550] 35 [240]
TP304LN S30453 75 [515] 30 [205]
. . . S30600 78 [540] 35 [240]
. . . S30601 78 [540] 37 [255]
. . . S30615 90 [620] 40 [275]
. . . S30815 87 [600] 45 [310]
TP309S S30908 75 [515] 30 [205]
TP309H S30909 75 [515] 30 [205]
TP309Cb S30940 75 [515] 30 [205]
TP309HCb S30941 75 [515] 30 [205]
. . . S31002 73 [500] 30 [205]
TP310S S31008 75 [515] 30 [205]
TP310H S31009 75 [515] 30 [205]
S31035 95 [655] 45 [310]
TP310Cb S31040 75 [515] 30 [205]
TP310HCb S31041 75 [515] 30 [205]
. . . S31050:
t # 0.250 in. 84 [580] 39 [270]
[6.35 mm]
t > 0.250 in. 78 [540] 37 [255]
[6.35 mm]
. . . S31254:
t # 0.187 in. [5.00 mm] 98 [675] 45 [310]
t > 0.187 in. [5.00 mm] 95 [655] 45 [310]
. . . S31266 109 [750] 61 [420]
. . . S31272 65 [450] 29 [200]
. . . S31277 112 [770] 52 [360]
TP316 S31600 75 [515] 30 [205]
TP316L S31603 70 [485] 25 [170]
TP316H S31609 75 [515] 30 [205]
. . . S31
...