ASTM A757 - A 757M - 22

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Designation: A757/A757M −22
Standard Speciﬁcation for
Steel Castings, Ferritic and Martensitic, for Pressure-
Containing and Other Applications, for Low-Temperature
Service
1
This standard is issued under the ﬁxed designation A757/A757M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This speciﬁcation covers carbon and alloy steel castings
for pressure-containing and other applications intended primar-
ily for petroleum and gas pipelines in areas subject to low-
ambient temperatures. Castings shall be heat treated by nor-
malizing and tempering or liquid quenching and tempering. All
classes are weldable under proper conditions. Hardenability of
some grades may limit usable section size.
1.2 The values stated in either inch-pound units or SI units
are to be regarded separately as standard. The values stated in
each system are not exact equivalents; therefore, each system
must be used independently of the other. Combining values
from the two systems may result in nonconformance with the
standard.
1.2.1 Unless the order speciﬁes an “M” designation, the
material shall be furnished to inch-pound units.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
2
A488/A488M Practice for Steel Castings, Welding, Qualiﬁ-
cations of Procedures and Personnel
A703/A703M Speciﬁcation for Steel Castings, General
Requirements, for Pressure-Containing Parts
A985/A985M Speciﬁcation for Steel Investment Castings
General Requirements, for Pressure-Containing Parts
A1067/A1067M Speciﬁcation for Test Coupons for Steel
Castings
2.2 American Society of Mechanical Engineers:
3
ASME Boiler and Pressure Vessel Code
2.3 Manufacturers Standardization Society of the Valve and
Fittings Industry Standards:
4
MSS SP-55 Quality Standard for Steel Castings for Valves,
Flanges, Fittings, and Other Piping Components—Visual
Method for Evaluation of Surface Irregularities
3. Terminology
3.1 Deﬁnitions of Terms Speciﬁc to This Standard:
3.1.1 nominal thickness, T, n—for quenched and tempered
castings with a thickness exceeding 2 in. [50 mm], the
maximum thickness of the pressure-containing wall of the
casting exclusive of padding added for directional
solidiﬁcation, ﬂanges, appendages, and sections designated by
the designer as noncritical.
4. General Conditions for Delivery
4.1 Except for investment castings, castings furnished to
this speciﬁcation shall be in accordance with the requirements
1
This speciﬁcation is under the jurisdiction of ASTM Committee A01 on Steel,
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee
A01.18 on Castings.
Current edition approved Nov. 1, 2022. Published December 2022. Originally
approved in 1978. Last previous edition approved in 2015 as A757/A757M – 15.
DOI: 10.1520/A0757_A0757M-22.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3
Available from American Society of Mechanical Engineers (ASME), ASME
International Headquarters, Three Park Ave., New York, NY 10016-5990, http://
www.asme.org.
4
Available from Manufacturers Standardization Society of the Valve and Fittings
Industry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http://www.mss-
hq.com.
*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
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.
1

of Speciﬁcation A703/A703M, including any supplementary
requirements that are indicated in the purchase order. Failure to
comply with the general requirements of Speciﬁcation A703/
A703M constitutes nonconformance with this speciﬁcation. In
case of conﬂict between the requirements of this speciﬁcation
and Speciﬁcation A703/A703M, this speciﬁcation shall pre-
vail.
4.2 Steel investment castings furnished to this speciﬁcation
shall conform to the requirements of Speciﬁcation A985/
A985M, including any supplementary requirements that are
indicated in the purchase order. Failure to comply with the
general requirements of Speciﬁcation A985/A985M consti-
tutes nonconformance with this speciﬁcation. In case of con-
ﬂict between the requirements of this speciﬁcation and Speci-
ﬁcation A985/A985M,A985/A985M shall prevail.
5. Ordering Information
5.1 Orders for material to this speciﬁcation should include
the following, as required, to describe the material adequately:
5.1.1 Quantity,
5.1.2 ASTM designation and date of issue,
5.1.3 Grade designation,
5.1.4 Class (if applicable),
5.1.5 Description of casting by part, pattern, or drawing
number (dimensional tolerances and machined surfaces should
be indicated on the casting drawing),
5.1.6 Options in the speciﬁcation,
5.1.7 Whether the castings are to be produced using invest-
ment casting process, and
5.1.8 Supplementary requirements desired, if any, including
standards of acceptance.
6. Materials and Manufacture
6.1 Melting Process—The steel shall be made by the electric
furnace process or other primary processes approved by the
purchaser. The primary melting may incorporate separate
degassing or reﬁning and may be followed by secondary
melting.
6.2 Heat Treatment:
6.2.1 All castings shall be heat treated by either normalizing
and tempering or quenching and tempering. Tempering tem-
perature shall be 1100 °F [595 °C] minimum, except grades
B4N and B4Q, which shall be tempered at 1050 °F [565 °C]
minimum.
6.2.2 E3N castings shall be heat treated by heating to
1850 °F [1010 °C] minimum, and air cooling to 200 °F [95 °C]
or cooler before any optional intermediate temper, but shall be
cooled to 100 °F [40 °C] or cooler before the ﬁnal temper,
which shall be between 1050 and 1150 °F [565 and 620 °C].
6.2.3 Furnace temperatures for heat treating shall be con-
trolled by thermocouples.
6.2.4 Castings shall be allowed to cool below the transfor-
mation range directly after pouring and solidiﬁcation before
they are reheated for normalizing or liquid quenching.
7. Chemical Composition
7.1 The steel shall be in accordance with the requirements
as to chemical composition prescribed in Table 1.
8. Tensile Requirements
8.1 Steel used for the castings shall conform to the require-
ments as to the tensile properties prescribed in Table 2.
9. Impact Requirements
9.1 Impact properties shall be determined on each heat by
testing a set of three Charpy V-notch specimens. The bar from
which the impact specimens are machined shall be prepared in
accordance with Section 12. The longitudinal axis of the
Charpy specimens shall be parallel to the longitudinal axis of
the tensile bar.
TABLE 1 Chemical Composition Requirements
A,B
Element, %
Grade
C
Type
A1Q
C
A2Q
C-Mn
B2N, B2Q
2.5Ni
B3N, B3Q
3.5Ni
B4N, B4Q
4.5Ni
C1Q
Ni-Mo
D1N, D1Q
Cr-Mo
E1Q
Ni-Cr-Mo
E2N, E2Q
Ni-Cr-Mo
E3N
Martensitic
Cr-Ni
Carbon 0.30 0.25
D
0.25 0.15 0.15 0.25 0.20 0.22 0.20 0.06
Manganese 1.00 1.20
D
0.50–0.80 0.50–0.80 0.50–0.80 1.20 0.40–0.80 0.50–0.80 0.40–0.70 1.00
Phosphorus 0.025
E
0.025
E
0.025
E
0.025
E
0.025
E
0.025
E
0.025
E
0.025
F
0.020
F
0.030
G
Sulfur 0.025
E
0.025
E
0.025
E
0.025
E
0.025
E
0.025
E
0.025
E
0.025
F
0.020
F
0.030
G
Silicon 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 1.00
Nickel 0.50
E
0.50
E
2.0–3.0 3.0–4.0 4.0–5.0 1.5–2.0 0.50
E
2.5–3.5 2.75–3.90 3.5–4.5
Chromium 0.40
E
0.40
E
0.40
E
0.40
E
0.40
E
0.40
E
2.0–2.75 1.35–1.85 1.50–2.0 11.5–14.0
Molybdenum 0.25
E
0.25
E
0.25
E
0.25
E
0.25
E
0.15–0.30 0.90–1.20 0.35–0.60 0.40–0.60 0.40–1.0
Copper 0.50
E
0.50
E
0.50
E
0.50
E
0.50
E
0.50
E
0.50
E
0.50
F
0.50
F
0.50
G
Vanadium 0.03
E
0.03
E
0.03
E
0.03
E
0.03
E
0.03
E
0.03
E
0.03
F
0.03
F
...
Tungsten . . . . . . . . . . . . . . . . . . 0.10
E
. . . 0.10
F
0.10
G
A
All values are maximums unless a range is provided.
B
Where ellipses (. . .) appear in this table, there is no requirement and the element need not be analyzed for or reported.
C
“Q” in the grade name indicates that the casting has been quenched and tempered. “N” in the grade name indicates that the casting has been normalized and tempered.
D
For each 0.01 % of reduction in carbon below the maximum speciﬁed, an increase of 0.04 % manganese over the maximum speciﬁed will be permitted up to 1.40 %.
E
The total content of these elements shall not exceed 1.00 % including phosphorus and sulfur.
F
The total content of these elements shall not exceed 0.70 % including phosphorus and sulfur.
G
The total content of these elements shall not exceed 0.50 % including phosphorus and sulfur.
A757/A757M − 22
2

9.2 Test temperature and absorbed energy requirements for

the grade shall be as speciﬁed in Table 3. Impact properties at

temperatures other than speciﬁed in Table 3 shall be agreed

upon between the manufacturer and the purchaser and Supple-

mentary Requirement S8 shall be speciﬁed. The average

energy value of three specimens shall not be less than the

minimum average speciﬁed, with only one value permitted

below the minimum average speciﬁed and this value not

permitted to fall below the minimum speciﬁed for a single

specimen. Supplementary Requirement S52 may be speciﬁed if

lateral expansion or percent shear area, or both, are desired by

the purchaser.

9.3 Impact properties shall also be determined on both the

heat-affected zone of the base metal and the weld metal of the

welding procedure qualiﬁcation test. Test temperature, energy

absorption, specimen type, and test method shall be the same as

speciﬁed for the base material.

9.3.1 Coupons Representing the Weld Deposits—Impact

specimens shall be located so that the longitudinal axis of the

specimen is at least one fourth of the thickness of the weld test

plate, t, from the surface of the test assembly and is transverse

to the longitudinal axis of the weld with the area of the notch

located in the weld metal. The length of the notch of the

Charpy specimen shall be normal to the surface of the weld

(see Fig. 1).

9.3.2 Coupons Representing the Heat-Affected Zone:

9.3.2.1 Impact specimens in test plate thicknesses greater

than

⁄

in. [16 mm] shall be from coupons removed from a

location as near as practical to a point midway between the

surface and center thickness. Heat-affected zone coupons for

TABLE 2 Tensile Requirements

Grade

Class Heat Treatment

C,D,E

Tensile Strength,

ksi [MPa]

Yield Strength

(0.2 % offset),

ksi [MPa]

Elongation in 2 in.

[50 mm], %

Reduction of

Area, %

A1Q . . . QT 65 [450] 35 [240] 24 35

A2Q . . . QT 70 [485] 40 [275] 22 35

B2N, B2Q . . . NT, QT

70 [485] 40 [275] 24 35

B3N, B3Q . . . NT, QT 70 [485] 40 [275] 24 35

B4N, B4Q . . . NT, QT 70 [485] 40 [275] 24 35

C1Q . . . QT 75 [515] 55 [380] 22 35

D1N, D1Q 1 NT, QT 85–115 [585–795] 55 [380] 20 35

D1N, D1Q 2 NT, QT 95–125 [655–860] 75 [515] 18 35

D1N, D1Q 3 NT, QT 105–135 [725–930] 85 [585] 15 30

E1Q . . . QT 90 [620] 65 [450] 22 40

E2N, E2Q 1 NT, QT 90–120 [620–825] 70 [485] 18 35

E2N, E2Q 2 NT, QT 105–135 [725–930] 85 [585] 15 30

E2N, E2Q 3 NT, QT 115–145 [795–1000] 100 [690] 13 30

E3N . . . NT 110 [760] 80 [550] 15 35

All values are minimums unless a range is provided.

“Q” in the grade name indicates the casting has been quenched and tempered. “N” in the grade name indicates the casting has been normalized and tempered.

QT = Quenched and tempered.

NT = Normalized and tempered.

NT, QT indicates that either a normalized and tempered or quenched and tempered heat treatment may be used.

TABLE 3 Charpy V-Notch Energy Requirements for Standard Size (10 mm by 10 mm) Specimens

Grade

Class Heat

Treatment

C,D,E

Maximum Effective

Section Size,

in. [mm]

Minimum Energy Value

for Two Specimens and

Minimum Average of

Three Specimens,

ft·lbf [J]

Minimum Energy Value

for Single Specimen,

ft·lbf [J]

Test Temperature

°F [°C]

A1Q . . . QT 1

⁄

[32] 13 [17] 10 [14] −50 [−46]

A2Q . . . QT 3 [75] 15 [20] 12 [16] −50 [−46]

B2N, B2Q . . . NT, QT 5 [125] 15 [20] 12 [16] −100 [−73]

B3N, B3Q . . . NT, QT 1

⁄

[32] 15 [20] 12 [16] −150 [−101]

B4N, B4Q . . . NT, QT 1

⁄

[32] 15 [20] 12 [16] −175 [−115]

C1Q . . . QT 5 [125] 15 [20] 12 [16] −50 [−46]

D1N, D1Q 1 NT, QT

FFFF

D1N, D1Q 2 NT, QT

FFFF

D1N, D1Q 3 NT, QT

FFFF

E1Q . . . QT

30 [41] 25 [34] −100 [−73]

E2N, E2Q 1 NT, QT 5 [125] 30 [41] 25 [34] −100 [−73]

E2N, E2Q 2 NT, QT 1

⁄

[32] 20 [27] 15 [20] −100 [−73]

E2N, E2Q 3 NT, QT 1

⁄

[32] 15 [20] 12 [16] −100 [−73]

E3N . . . NT 1

⁄

[32] 20 [27] 15 [20] −100 [−73]

Hardenability and residual elements (primarily P & S levels) in some of the grades may limit the maximum section size in which these impact values can be obtained.

“Q” in the grade name indicates the casting has been quenched and tempered. “N” in the grade name indicates the casting has been normalized and tempered.

QT = Quenched and tempered.

NT = Normalized and tempered.

NT, QT indicates that either a normalized and tempered or quenched and tempered heat treatment may be used.

Requirements shall be subject to agreement between the manufacturer and the purchaser.

A757/A757M − 22

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摘要：

ASTM A757 - A 757M - 22 是国际材料与试验协会（ASTM）发布的最新标准规范，主要涵盖用于低温及高温压力容器、阀门及其他关键部件的铁素体与马氏体钢铸件的技术要求。该标准于2022年修订发布，明确了材料的化学成分、力学性能、热处理工艺、无损检测及验收标准，尤其适用于石油化工、能源及海洋工程等对材料韧性与强度要求严苛的领域。通过采用该规范，制造商可确保铸件在极端温度下仍具备可靠的使用寿命与安全性，同时便于全球采购与质量一致性管控。

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