ASTM A758/A758M-14(2019)
(Specification)Standard Specification for Wrought-Carbon Steel Butt-Welding Piping Fittings with Improved Notch Toughness
Standard Specification for Wrought-Carbon Steel Butt-Welding Piping Fittings with Improved Notch Toughness
ABSTRACT
This guide covers standard specification for wrought-carbon steel butt-welding seamless or welded fittings specially processed to ensure better notch toughness. Heat treatment shall be required for all types of fittings. Fittings with mandatory radiographic examination of welds shall be included. Cast fittings and fittings formed from all weld metal, shall not be included. Heat or cast analysis shall be conducted wherein the material shall conform to the required chemical components for carbon, manganese, phosphorus, sulfur, silicon, vanadium, chromium, nickel, molybdenum, copper, and lead. The fittings, as represented by tensile test specimens taken subsequent to final heat treatment, shall conform to the specified values of tensile strength, yield strength, and elongation for the applicable grades of steel. Mechanical tests such as tension test and transverse guided weld bend test shall be performed on the fittings.
SCOPE
1.1 This specification covers wrought-carbon steel butt-welding seamless or welded fittings specially processed to ensure better notch toughness than that to be expected in fittings manufactured to the requirements of Specification A234/A234M.
1.1.1 Included are elbows, caps, tees, reducers, and other type fittings covered by ASME B16.9.
1.1.2 Heat treatment is required for all fittings.
1.1.3 Fittings with mandatory radiographic examination of welds are included.
1.1.4 Supplementary requirements are provided for use when additional testing or examination is desired.
1.1.5 Cast fittings, and fittings formed from all weld metal, are not included.
1.2 Several type of fittings are provided, as follows:
Type
Heat Treatment
Required
Weld Seam
Finish (5.3.2)
Radiography
Required?
30
normalize
UW-35
no
31
normalize
UW-35
yes
32
normalize
UW-35 and ground flush
yes
40
normalize and temper
UW-35
no
41
normalize and temper
UW-35
yes
42
normalize and temper
UW-35 and ground flush
yes
50
quench and temper
UW-35
no
51
quench and temper
UW-35
yes
52
quench and temper
UW-35 and ground flush
yes
1.3 It shall be the responsibility of the purchaser to determine whether material meeting the requirements of this specification is satisfactory for the service application.
1.4 This specification is expressed in both inch-pound units and SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material shall be furnished to inch-pound units.
1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.
1.6 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
Relations
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:A758/A758M −14 (Reapproved 2019)
Standard Specification for
Wrought-Carbon Steel Butt-Welding Piping Fittings with
Improved Notch Toughness
This standard is issued under the fixed designationA758/A758M; 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 SI units are shown in brackets. The values stated in each
system may not be exact equivalents; therefore, each system
1.1 This specification covers wrought-carbon steel butt-
shall be used independently of the other. Combining values
welding seamless or welded fittings specially processed to
from the two systems may result in non-conformance with the
ensure better notch toughness than that to be expected in
standard.
fittings manufactured to the requirements of Specification
A234/A234M.
1.6 This international standard was developed in accor-
1.1.1 Included are elbows, caps, tees, reducers, and other
dance with internationally recognized principles on standard-
type fittings covered by ASME B16.9.
ization established in the Decision on Principles for the
1.1.2 Heat treatment is required for all fittings.
Development of International Standards, Guides and Recom-
1.1.3 Fittings with mandatory radiographic examination of
mendations issued by the World Trade Organization Technical
welds are included.
Barriers to Trade (TBT) Committee.
1.1.4 Supplementary requirements are provided for use
when additional testing or examination is desired.
2. Referenced Documents
1.1.5 Cast fittings, and fittings formed from all weld metal,
2.1 In addition to those reference documents listed in
are not included.
Specification A960/A960M, the following list of standards
1.2 Several type of fittings are provided, as follows:
apply to this specification:
Heat Treatment Weld Seam Radiography
Type Required Finish (5.3.2) Required?
2.2 ASTM Standards:
A234/A234M Specification for Piping Fittings of Wrought
30 normalize UW-35 no
31 normalize UW-35 yes
Carbon Steel and Alloy Steel for Moderate and High
32 normalize UW-35 and ground flush yes
Temperature Service
40 normalize and temper UW-35 no
A275/A275M Practice for Magnetic Particle Examination of
41 normalize and temper UW-35 yes
42 normalize and temper UW-35 and ground flush yes
Steel Forgings
50 quench and temper UW-35 no
A960/A960M Specification for Common Requirements for
51 quench and temper UW-35 yes
Wrought Steel Piping Fittings
52 quench and temper UW-35 and ground flush yes
E165 Practice for Liquid Penetrant Testing for General
1.3 It shall be the responsibility of the purchaser to deter-
Industry
mine whether material meeting the requirements of this speci-
E709 Guide for Magnetic Particle Testing
fication is satisfactory for the service application.
2.3 ASME Boiler and Pressure Vessel Code (ASME Code):
1.4 This specification is expressed in both inch-pound units
Section VIII, Division 1
and SI units. However, unless the order specifies the applicable
Section IX
“M” specification designation (SI units), the material shall be
furnished to inch-pound units.
2.4 ASME Standard:
B16.9 Standards for Steel Butt-Welding Fittings
1.5 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. Within the text, the
1 2
This specification is under the jurisdiction ofASTM Committee A01 on Steel, For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
A01.22 on Steel Forgings andWrought Fittings for PipingApplications and Bolting Standards volume information, refer to the standard’s Document Summary page on
Materials for Piping and Special Purpose Applications. the ASTM website.
Current edition approved Dec. 1, 2019. Published December 2019. Originally Available from American Society of Mechanical Engineers (ASME), ASME
approved in 1978. Last previous edition approved in 2014 as A758/A758M – 14. International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
DOI: 10.1520/A0758_A0758M-14R19. www.asme.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A758/A758M−14 (2019)
2.5 ASNT Standard: 5.4.3 Types 50, 51, and 52 fittings shall be quenched-and-
SNT-TC-1A Practice for Nondestructive Examination Per- tempered by uniformly heating to a temperature in the austen-
sonnel Qualification and Certification itizing range, but not to exceed 1700 °F [925 °C], and then
quenching in a liquid media from the austenitizing temperature
3. Ordering Information
to a temperature below 800 °F [425 °C]. After quenching, the
fittings shall be reheated to a temperature in the range from
3.1 See Specification A960/A960M.
1100 °F to 1250 °F [595 °C to 675 °C], soaking at that
4. General Requirements
temperature for ⁄2 h minimum per 1 in. [25 mm] of thickness,
but not less than 15 min, and then air-cooled to room
4.1 Product furnished to this specification shall conform to
temperature.
the requirements of Specification A960/A960M, including any
supplementary requirements that are indicated in the purchase
6. Chemical Composition
order. Failure to comply with the requirements of Specification
A960/A960M constitutes non-conformance with this specifi- 6.1 Heat or CastAnalysis—The results shall conform to the
cation. In case of a conflict between the requirements of this requirements for the applicable grade as specified in Table 1.
specificationandSpecificationA960/A960M,thisspecification
6.2 Product Analysis—The purchaser may make a product
shall prevail.
analysis on products made to this specification in accordance
with Specification A960/A960M.
5. Materials and Manufacture
6.3 The steel shall not contain any unspecified elements for
5.1 The steel shall be killed and shall be melted to a fine
the ordered grade to the extent that it conforms to the
austenitic grain size practice.
requirements of another grade for which that element is a
5.2 Thestartingmaterialshallbewroughtandintheformof
specified element having a required minimum content.
blooms, billets, slabs, forgings, bars, plates, sheets, seamless
pipe or tube, or welded-with-filler-metal pipe or tube. Cast
7. Mechanical Requirements
products shall not be used.
7.1 Tensile Requirements:
5.3 Any forming process, fusion-welding process, or com-
7.1.1 The fittings, as represented by tensile test specimens
bination of such processes, may be used. taken subsequent to final heat treatment, shall conform to the
5.3.1 Allweldingshallbefusion-weldedinaccordancewith
requirements for the applicable grade as specified in Table 2.
the requirements of Section IX of the ASME Boiler and 7.1.2 Number and Location of Specimens:
Pressure Vessel Code. Welding procedures, welders, and weld-
7.1.2.1 Lot—For tension testing, a lot shall consist of the
ing operators shall be qualified in accordance with Section IX fittings from a heat, in each heat treatment charge, with
of the ASME Boiler and Pressure Vessel Code.
nominal wall thicknesses within ⁄4 in. [6 mm] of the nominal
5.3.2 All welded joints shall be finished in accordance with thickness of the test specimen. In addition, for Types 32, 42,
Paragraph UW-35 of Section VIII, Division 1, of the ASME and 52, the lot definition shall include each heat or lot of weld
Code.
metal. If heat treatment is performed in a continuous or
5.3.3 Welded joints of Type 32, 42, and 52 shall be ground batch-type furnace controlled within a range of plus-or-minus
flush.
25 °F [14 °C] and equipped with calibrated thermocouples and
5.3.4 Welded joints ofTypes 31, 41, 51, 32, 42, and 52 shall recording pyrometers, and records of heat treatment are
be examined by radiography in accordance with the require-
maintained, all fittings heat treated in such a furnace are
ments of Paragraph UW-51 of Section VIII, Division 1, of the
ASME Code, and shall conform to the requirements of
Paragraph UW-51.
TABLE 1 Chemical Requirements
Element Cast or Heat
5.4 Heat Treatment—All fittings shall be heat treated sub-
Analysis
sequent to final welding and forming.
5.4.1 Types 30, 31, and 32 fittings shall be normalized by
Carbon, max, % 0.27
uniformly heating to a temperature in the austenitizing range,
Manganese, % 0.85–1.20
Phosphorus, max, % 0.035
but not to exceed 1700 °F [925 °C], and subsequently removed
Sulfur, max, % 0.035
from the furnace and air-cooled individually to room tempera-
Silicon, % 0.15–0.30
ture.
Vanadium, max, % 0.05
A,B
Residual elements
5.4.2 Types 40, 41, and 42 fittings shall be normalized in
Chromium, max, % 0.25
accordance with 5.4.1. After normalizing, the fittings shall be
Nickel, max, % 0.25
temperedbyheatingtoatemperatureintherangefrom1100°F
Molybdenum, max, % 0.08
Copper, max, % 0.35
to 1200 °F [595 °C to 675 °C], soaking at that temperature for
Lead, max, % 0.05
⁄2 h minimum per 1 in. [25 mm] of thickness, but not less than
A
Individual limits of chromium, nickel, molybdenum, and copper may be exceeded
15 min, and then air-cooled to room temperature.
by 0.05 % provided that their total does not exceed 0.90 % in both the heat and
product analysis.
B
These are not to be added to the melt and shall only occur as a result of
AvailablefromAmericanSocietyforNondestructiveTesting(ASNT),P.O.Box
unavoidable residuals from the melting stock.
28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http://www.asnt.org.
A758/A758M−14 (2019)
TABLE 2 Tensile Requirements
quent to final heat treatment, in accordance with Section IX of
Grade 60 Grade 70 the ASME Boiler and Pressure Vessel Code.
7.2.3 Requirement—The guided-bend test specimen shall
Tensile strength, ksi [MPa] 60 to 85 [415 to 585] 70 to 95 [485 to 635] 1
not have any cracks or other open defects exceeding ⁄8 in. [3
A
Yield strength, min, ksi 35 [240] 38 [260]
mm], measured in any direction on the convex surface of the
[MPa]
Elongation in 2 in. [50 mm],
specimen after bending. Cracks occurring on the corners of the
min, %
specimen during testing shall not be considered unless there is
Longitudinal 30 27
definite evidence that they result from slag inclusions or other
Transverse 22 20
A internal defects.
0.2 % offset or 0.5 % EUL.
8. Dimensions
8.1 Butt-welded fittings shall conform to the dimensions
considered to be in one charge. For furnaces not so equipped
and tolerances specified in ASME B16.9.
and controlled, each batch constitutes a charge.
7.1.2.2 Representative Test Piece—For instances in which
9. Surface Finish, Appearance, and Corrosion Protection
the tension test specimen cannot be obtained from a fitting due
to size limitations, a representative test piece may be used.The
9.1 The requirements of Specification A960/A960M apply.
test piece shall be from the same heat and shall be heat treated
in the same heat treatment batch or charge as the fittings it
10. Radiographic Examination
represents, and shall have had approximately the same amount
10.1 Types 31, 32, 41, 42, 51, and 52 fittings shall have the
of working as the fittings. In addition, for fittings manufactured
entire length of each weld joint examined radiographically in
from bars, plate, or forgings, the test piece shall have a
accordance with Paragraph UW-51 of SectionVIII, Division 1,
cross-section equal to or larger than the greatest cross-section
of the ASME Boiler and Pressure Vessel Code.
of the fittings it represents. Test pieces representing fittings
10.2 Radiographic examination may be performed prior to
manufactured from pipe shall have a nominal outside diameter
final heat treatment.
and wall thickness equal to that of the pipe from which the
fitting was formed. Test pieces for fittings fabricated by
10.3 Personnel performing radiographic examination shall
weldingorformedfromweldedpipeshallbepreparedwiththe
be qualified and certified in accordance with SNT-TC-1A-
same welding procedure and from the same heat or lot of weld
1984, or with the approval of the purchaser, in accordance with
metal as the fitting it represents.
another nationally-accepted standard which covers the qualifi-
7.1.2.3 Types 30, 31, 40, 41, 50, and 51—One base-metal
cation and certification of radiographic examination personnel.
tension test specimen shall be tested from each lot. For fittings
fabricated by welding, one transverse-weld tension test speci- 11. Rework and Retreatment
men shall also be made from each lot. One traverse-weld
11.1 See Specification A960/A960M.
tension test specimen shall also be required from each lot for
11.2 Repair Welding—Parent Metal:
fittingsformedfromweldedpipeiftheweldintheweldedpipe
11.2.1 Repair welding by the manufacturer is permissible
was not tested in the same heat treatment condition as the
for parts made to dimensional standards, in ASME or equiva-
fittings.
lent standards.
7.1.2.4 Types 32, 42, and 52—One base-metal and one
11.2.2 Prior approval of the purchaser shall be required to
transverse-weldtensiontestspecimenshallbetestedfromeach
weld repair special parts made to the purchaser’s requirements.
lot. Fittings fabricated by welding or formed from welded pipe
11.2.3 Welding shall produce low hydrogen in the weld-
shall be tested as in 7.1.2.3.
ment.
7.1.2.5 Tension test specimens shall be taken from an
11.2.4 The product shall be heat treated in accordance with
integral part of the fitting where practicable. All base-metal
Section 5 after weld repair.
tension tests shall be conducted in the longitudinal direction.
Weld metal specimens shall be taken transverse to the weld.
12. Inspection
7.1.2.6 Yield strength shall be determined either by the
0.2 %offsetmethodorthe0.5 %extension-under-loadmethod. 12.1 The manufacturer shall afford the purchaser’s inspec-
tors all reasonable facilities necessary to satisfy him that the
7.2 Transverse Guided Weld Bend Tests—Welded Fittings
material is being produced and furnished in accordance with
Only:
this specification. Inspection by the purchaser shall not inter-
7.2.1 Number of Tests:
fere unnecessarily with the manufacturer’s operations.All tests
7.2.1.1 Lot—A lot shall be as defined in 7.1.2.1.
and inspections shall be made at the place of manufacture,
7.2.1.2 One guided face-bend and one guided root-bend test
unless otherwise agreed to.
shall be made to represent each lot for fittings with a nominal
wall thickness of ⁄8 in. [10 mm] and less. For fittings with a
13. Rejection and Reh
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